Document QRN9yNx6BL5VRZ2w4NLxvEG4

Z88.2-1969 This coov ' provided as a public service by the mem* ben ol the Industrial Sale* ty Equipment Association. Inc 4 practices for respiratory protection ANSI Z88JM969 American National Standard Practices for Respiratory Protection Sponsor U. S. Department of the Interior Bureau of Mines Approved August 11, 1969 American National Standards Institute, Inc 3n I American National Standard An American National Standard implies a consensus of those sub* stantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the genera] public. The existence of an American National Standard does not in any respect preclude anyone, whether he has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review and users are cautioned to obtain the latest editions. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Institute require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of publication. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute. Published by American National Standards Institute, Inc 1430 Broadway, New York, New York 10018 Copyright 1969 by the American National Standards Institute. Inc No portion of thit publication may bo quoted or reproduced in any form uritAout tho uiritton ptrmittion of tho Amorican National Standards Institute. Printed in USA ASM 172/450 ft Foreword (This Foreword is not part of American National Standard Practices for Respiratory Protection. 288.2-1969.) This is a revision of the respiratory protection portion of American National Standard Safety Code for Head, Eye, and Respiratory Protection, Z2.1-1959. The United States Department of the Interior, Bureau of Mines, which acted as cosponsor of Z2.1-1959, accepted sponsorship of the proj ect on respiratory protection when it was deemed advisable to separate the portions of that Z2.1 standard. A Z88 Standards Committee was organized and met on September 24, 1963, to review the section of Z2.1-1959 dealing with respiratory protection. The Committee decided to revise and rewrite that section. The fifth draft of the proposed standard was submitted to letter ballot and accepted by the' Z88 Committee on May 2, 1969. It was approved as an American National Stan dard on August 11. Since questions may arise from time to time concerning interpretation of this standard, an Inter pretation and Review Committee has been established, to provide for the uniform handling of doubtful cases. Anyone using this standard and desiring an interpretation may communicate with the Standards Institute. The Committee will also review new developments in respiratory protection and determine the need for revision or supplementation of this standard. Suggestions for improvement gained in the use of this standard will be welcome. They should be sent to the American National Standards Institute, 1430 Broadway, New York, N.Y. 10018. The Z88 Standards Committee had the following personnel at the time it approved this standard. Robert H. Schutz, Chairman Francis X. Worden, Secretary Organisation Represented American Conference of Governmental Industrial Hygienists American Foundrymen'a Society___________ ________________ American Gas Association________ ________ __________ .......... American Industrial Hygiene Association__ ____ __ American Insurance Association ......__ .____ ___ ..... American Mutual Insurance Alliance__ ___ American Petroleum Institute__ ____ __ -- American Society of Mechanical Engineers American Society of Safety Engineers ___ _ American Welding Society________ ___ __ Association of American Railroads ............. Electronic Industries Association................. Ceneral Services Administration......... ............. ........... Industrial Medical Association__ ____________ ......................... Industrial Safety Equipment Association............. ..................... International Association of Fire Chiefs....................... International Association of Governmental Labor Officials...... National Safety Council______________ _______ _____________ Telephone Croup.... ...... ..... ......... ........... U. S. Atomic Energy Commission......... Name o/ Representative .........__ E. C. Hyatt -------------William B. Huelsen ........__ ..T. L. Powers H. W. Becker (All) ------------ E- C. Hyatt W. H. Revoir (Alt) ----------Robert R. Conroy Victor Bohn (Alt) -------------J. A. Houghton Frederick H. Deeg (Alt) ........... ,,..W. E. Carroll J. F. McKenna (AU) ----__ Thomas R. Curran ........^..Richard H. Burr Harold Ritchie (Alt) -------------A. D. Brandt -------------D. P. Russell ...............F. X. Worden James J. Sullivan (Alt) .........__ .Lane Parsons ..............Ernest M. Dixon .............. Eugene W. Merry Benjamin Smilg Harley N. Trice Charles N. Sumwalt (All) Howard M. Weiss (Alt) ...............Raymond J. Brady Donald M. O'Brien (Alt) -------------Martin Slotkin .........--..H. H. Fawcett Julian B. Olishifski (Alt) ............... F. X. Worden ...............Carl G. Weity. Jr Humphery Gilbert (Alt) 3/3 Organisation Represented U. S. Coast Guard__________ ......____ U. S. Department of Agriculture ......... U. S. Department of the Army ............. U. S. Department of the Interior ---. U. S. Department of Labor ------... U. S. Department of the Navy-------- - U. S. Public Health Service (Liaison) Individual Member_-______ Name of Representative ------ --------- --Norman W. Lomlcy ------------________Rolland M. Waters ------------------------------- --..Robert A. Duguid Harry H. Ackerman (AU) ......-------------- --.... ----Robert H. Schutz E. J. Kloos (Alt) .--.------------ --------G. Walker Daubenspeck John O'Neill (AU) .--................. .............Samuel H. Barboo. Jr N. E. Roeenwinkel (AU) ....-------- --.._____ Howard E. Ayer Charles H. Powell (Alt) -----------------------------------William E. Clark Hie subcommittee which prepared the final draft on this standard had the following personnel. H. H. Ackerman Raymond J. Brady R. H. Burr Carl G. Welty, Jr, Chairman H. H. Fawcett E. C. Hyatt W. H. Revoir Contents SECTION PACE 1. Introduction ................................................................................................................................... " 2. Definitions....................................................................................................................................... 7 3. Recommended Requirements for Codes........................................................................................ 9 4. Classification of Respiratory Hazards............................................................................................ 11 5. Classification, Description, and Limitations of Respirators......................................................... 11 6. Selection of Respirators................................................................................................................. 13 6.1 Approved or Accepted Respirators...................................................................................... 13 6.2 General Considerations........................................................................................................ 13 6.3 Nature of the Hazard........................................................................................................... 13 6.4 Extent and Location of Hazard............................................................................................ 22 6.5 Work Requirements and Conditions.................................................................................. 22 6.6 Employee Acceptance and Face Fit.................................................................................... 23 7. Use of Respirators........................................................................................................................... 23 7.1 Operating Procedures........................................................................................................... 23 7.2 Issuance of Respirators....................................... '............................................................... 23 7.3 Use in Dangerous Atmospheres............................................................................................23 7.4 Training and Education in Proper Use.............................................................................. 24 7.5 Facepiece Fit Tests and Procedures.................................................................................... 24 8. Maintenance and Care of Respirators.......................................................................................... 25 8.1 General ......................-.....................................................'....................................................25 8.2 Inspection ....................................... ...... .'..................................................................... ....... 25 8.3 Cleaning and Disinfection.................................................................................................... 25 8.4 Repair ................................................................................................................................... 26 8.5 Storage ................................................................................................................................. 26 9. Special Problems ................................................................................ 26 9.1 Corrective Lens with Full Facepiece......................................................................................26 9.2 Eyewear with Half-Mask Facepiece.................................................................................... 26 9.3 Respirator Use in Low Temperatures........................................................... 26 9.4 Respirator Use in High Temperatures................................................................................ 27 9.5 Communications..................................................................................................................... 27 9.6 Nonconventional Respirators.... ...........................................................-............................ 27 10. Evaluation of Respirator Program Effectiveness.......................................................................... 27 10.1 General .................................................................................................................................. 27 10.2 Wearer Acceptance............................................................................................................... 28 10.3 Examination of Respirators in Use.................................................................................... 28 10.4 Evaluation of Protection Afforded...................................................................................... 28 11. References to Other Codes, Standards, and Manuals.................................................................. 28 Apiwndix Respirator Approval and Acceptance Listings.................................................................. 30 Tables Table 1 Classification of Respiratory Hazards According to Their Biological Effect................. 10 Table 2 Classification of Respiratory Hazards According to Their Properties which Influence Respirator Selection........................................................................................................... 12 Table 3 Classification and Description of Respirators by Mode of Operation........................ 14-15 Table 4 Capabilities and Limitations of Respirators.............................................................. 16-17 Table 5 Color Code for Gas Mask Canisters..................................... ............................................ 18 Table 6 Guide for Selection of Respirators ................................................................................. 19 2/S' American National Standard Practices for Respiratory Protection 1. Introduction This standard sets forth accepted practices for respirator users. It provides information and guidance on the proper selection, use, and care of respirators and sets forth recommended re quirements suitable for adoption into regula tions governing their use. 1.1 Scope. The scope of this standard includes safe practices and requirements for using res pirators for protection of the respiratory system from inhalation of particulate matter, noxious gases and vapors, and oxygen deficiency. Ex cluded are 1) underwater protection, 2) highaltitude aircraft oxygen systems, and 3) pro tection against military munitions. Although the standard does not cover engineered protective measures (for example, ventilation), exposure control shall be accomplished as far as is fea sible by accepted engineering methods before considering or instituting use of respirators. 1.2 Purpose. The standard is intended to pro vide guidance that will assist respirator users in safeguarding health and life through proper selection and use of respirators. Use of respira tors implies that the wearer needs protection from an atmosphere that might threaten his life or health. Therefore, it is imperative that the level of protection needed be determined and provided in both normal and emergency condi tions of use, particularly if exposure to the at mosphere couid be immediately dangerous to life or health. Use of respirators in atmospheres that are dangerous to life or health is discussed in 6.3. 1.3 "Shall" and "Should". The provisions of this standard are mandatory in nature where the word "shall" is used and advisory in nature where the word "should" is used. 1.4 Exceptions. Exceptions to the requirements in Section 3, Recommended Requirements for Codes, may be granted by competent authority, provided that an equally acceptable mode and degree of protection is afforded. 2. Definitions abrasive-blasting respirator. See respirator. aerodynamic diameter. The diameter of a unit density sphere having the same settling velocity as the particle in question of whatever shape and density. air-line respirator. See respirator. air-purifying respirator. See respirator. air-regulating valve. An adjustable valve used to regulate airflow to the facepiece, helmet, or hood of an air-line respirator, air-supply device. A hand- or motor-operated blower for the hose mask, or a compressor or other source of respirable air for air-line and abrasive-blasting respirators, approved. Tested and listed as satisfactory by an authority having jurisdiction, such as U.S. Department of the Interior, Bureau of Mines, or U.S. Department of Agriculture, breathing tube. A tube through which air or oxygen flows to the facepiece, helmet, or hood, canister (air-purifying). A container filled with sorbents and catalysts that remove gases and vapors from air drawn through the unit The canister may also contain an aerosol (particu late) filter to remove solid or liquid particles, canister (oxygen-generating). A container filled with a chemical which generates oxygen by chemical reaction. cartridge. A small container filled with air-puri fying media. catalyst. In respirator use, a substance which converts a toxic gas (or vapor) into a less-toxic gas (or vapor). chemical-cartridge respirator. See respirator. contaminant. A harmful, irritating, or nuisance material that is foreign to the normal atmo sphere. corrective lens. A lens ground to the wearer's individual corrective prescription, detachable coupling. A device by means of which the respirator wearer, without using hand- 7 Z88.2 AMERICAN NATIONAL STANDARD PRACTICES tools, may detach the air-supply line from that part of the respirator worn on the person or from the air-supply source, disinfection. The destruction and removal of pathogenic organisms, especially by means of chemical substances. dust. See Table 2. exhalation valve. A device that allows exhaled air to leave a respirator and prevents outside air from entering through the valve, eyepiece. A gastight, transparent window(s) in a full facepiece through which the wearer may see. ' facepiece. That portion of a respirator that covers the wearer's nose and mouth in a half mask facepiece or nose, mouth, and eyes in a full facepiece. It is designed to make a gas-tight or dust-tight fit with the face and includes the headbands, exhalation valve(s), and connec tions for air-purifying device or respirable-gas source or both. filter respirator. See respirator. filler. A fibrous media (canned or uncanned) used in respirators to remove solid or liquid particles from the airstream entering the res pirator enclosure. fog. See Table 2. full facepiece. See facepiece. fume. See Table 2. gas. An aeriform fluid which is in the gaseous state at ordinary temperature and pressure, gas mask. See respirator. half-mask facepiece. See facepiece. head harness, a device for holding the face piece securely in place on the wearer's head. helmet. A device that shields the eyes, face, neck, and other parts of the head, hood. A device that completely covers the head, neck, and portions of the shoulders. hose mask. See respirator. immediately dangerous to life or health. In cluded are conditions that pose an immediate threat to life or health and conditions that pose an immediate threat of severe exposure to con taminants such as radioactive materials which are likely to have adverse delayed effects on health. inhalation valve. A device that allows respirable air to enter the facepiece and prevents exhaled air from leaving the facepiece through the intake opening. irrespirable. Unfit for breathing, mist. See Table 2. MPC. Maximum permissible concentration. These concentrations are set by the National Committee on Radiation Protection. They are recommended maximum average concentrations of radionuclides to which a worker may be ex posed, assuming that he works 8 hours a day, 5 days a week, and 50 weeks a year. particulate matter. A suspension of fine solid or liquid particles in air, such as dust, fog, fume, mist, smoke, or sprays. Particulate matter sus pended in air is commonly known as an aerosol, pneumoconiosis-producing dust. Dust, which when inhaled, deposited, and retained in the lungs, may produce signs, symptoms and find ings of pulmonary disease, resistance. Opposition to the flow of air, as through a canister, cartridge, particulate filter, or orifice. respirable. Fit to be breathed, respirator. A device designed to protect the wearer from inhalation of harmful atmospheres. See Section 5, Classification, Description, and Limitations of Respirators. self-contained breathing apparatus. See res pirator. sorbent. A material which removes toxic gases and vapors from air inhaled through a canister or cartridge, spray. See Table 2. supplied-air respirator. See respirator. supplied-air suit. A one- or two-piece suit that is impermeable to most particulate and gaseous contaminants and is provided with an adequate supply of respirable air. TLV. Threshold limit value. A table of these values and accompanying precautions is pub lished annually by the American Conference of Governmental Industrial Hygienists, toxic dust. Dust that may be harmful to the respiratory system or to other parts of the body through passing from the respiratory tract into the blood stream. valve (air or oxygen). A device which controls the direction of air or oxygen flow or the rate and pressure at which air or oxygen is delivered, or both. 3n FOR RESPIRATORY PROTECTION Z88.2 vapor. The gaseous state of a substance that is solid or liquid at ordinary temperature and pressure. window indicator. A colorimetric indicator for gas mask canisters which denotes the service life for a particular gas. 3. Recommended Requirements for Codes 3.1 Purpose. This section includes recom mended requirements for authorities consider ing establishment of respirator regulations or codes. The following recommended requirements are supplemented by recommended practices in subsequent sections of this standard. 32 Permissible Practice. In the control of those occupational diseases caused by breath ing air contaminated with harmful dusts, fogs, fumes, mists, gases, smokes, sprays, or vapors, the primary objective shall be to prevent atmo spheric contamination. This shall be accom plished as far as feasible by accepted engineer ing control measures (for example, enclosure or confinement of the operation, general and local ventilation, and substitution of less toxic mate rials). When effective engineering controls are not feasible, or while they are being instituted, appropriate respirators shall be used pursuant to the following requirements. U Employer Responsibility 321 Respirators shall be provided by the employer when such equipment is necessary to protect the health of the employee. 322 The employer shall provide the respira tors which are applicable and suitable for the purpose intended. 322 The employer shall be responsible for the establishment and maintenance of a respiratory protective program which shall include the gen eral requirements outlined in 3.5. 3.4 Employee Responsibility 32.1 The employee shall use the provided res piratory protection in accordance with instruc tions and training received. 322 The employee shall guard against dam age to the respirator. 322 The employee shall report any malfunc tion of the. respirator to the responsible person. 32 Minimal Acceptable Program ^ 32.1 Written standard operating procedures governing the selection and use of respirators shall be established. 322 Respirators shall be selected on the basis of hazards to which the worker is exposed. See Section 4, Classification of Respiratory Hazards. 322 The user shall be instructed and trained in the proper use of respirators and their limita tions. See 7.4 and 7.5. 322 Where practicable, the respirators should be assigned to individual workers for their ex clusive use. 322 Respirators shall be regularly cleaned and disinfected. Those issued for the exclusive use of one worker should be cleaned after each day's use, or more often if necessary. Those used by more than one worker shall be thor oughly cleaned and disinfected after each use. See 82. 32.6 Respirators Shall be stored in a con venient, clean, and sanitary location. See 8.5. 32.7 Respirators used routinely shall be in spected during cleaning. Worn or deteriorated parts shall be replaced. Respirators for emer gency use such as self-contained devices shall be thoroughly inspected at least once a month and after each use. See 82. 322. Appropriate surveillance of work area conditions and degree of employee exposure or stress shall be maintained. See 6.3.4 and 10.4. 322 There shall be regular inspection and evaluation to determine the continued effec tiveness of the program. See Section 8, Mainte-. nance and Care of Respirators, and Section 10, Evaluation of Respirator Program Effectiveness. 26 Program Administration. The plant or company industrial hygiene, health physics, safety engineering, or fire department shall ad minister the program in close liaison with the - plant medical department. Responsibility for the program shall be vested in one individual. In small plants having no formal industrial hy giene, health physics, safety, fire, or medical department, the respirator program shall be administered by an upper-level superintendent, foreman, or other qualified individual respon sible to the principal manager. The administra tor shall have sufficient knowledge of the subject to properly supervise the program. Table 1 Classification of Respiratory Hazards According to Their Biological Effect Oxygen Deficiency Occurrence: Confined or unventilated cellars, wells, mines, ship holds, tanks, burning buildings, and enclosures containing inert atmospheres. (See Note 1.) Atmospheric O2 content (percent by volume) versus expected conditions: 20.9 percent: Oxygen content of normal air. 16 percent: Flame of safety lamp or ordinary combustibles extinguished, and symptoms of anoxia begin to appear in humans. Gas and Vapor Contaminants Particulate Contaminants (Dust, fog, fume, mist, smoke, and sprays) Asphyxiants: Interfere with utilization of O2 in the body. Simple asphyxiants: Physiologically inert sub stances that dilute O2 in the air (for example, nitrogen, hydrogen, helium, methane). See Oxygen Deficiency, Column 1. Chemical asphyxiants: Low concentrations in terfere with supply or utilization of O2 in the body (for example, carbon monoxide, hydrogen cyanide, cyanogen and nitriles). Irritants: Corrosive in action. May cause irritation and inflammation of parts of the respiratory system (also skin and eyes) and pulmonary edema (for example, ammonia, hydrogen chloride, form aldehyde, sulfur dioxide, chlorine, ozone, nitro gen dioxide, phosgene, and arsenic trichloride). Anesthetics: Cause loss of feeling and sensation with unconsciousness and death possible (for example, nitrous oxide, hydrocarbons and ethers). Some anesthetics injure body organs; for example, carbon tetrachloride (liver and kidneys), chloro form (liver and heart), benzene (bone marrow), and carbon disulfide (nervous system). Systemic poisons: Damage organs and systems in the body; for example, mercury (nervous system and various organs), phosphorous (bone), hydro gen sulfide (respiratory paralysis), and arsine (red blood cells and liver). Relatively inert: May cause discomfort and minor irritation, but generally without injury at reason able concentrations (for example, marble, gyp sum). Pulmonary fibrosis-producing; Produce nodulation and fibrosis in the lung, possibly leading to com plications (for example, quartz, cristobalite, tridymite, asbestos). Cancer-producing: Produce cancer in some indi viduals after "latent" period of 20-40 years (for example, asbestos, chromates, radioactive particu lates). Chemical irritants: Produce irritation, inflammation, ulceration, and so forth, in upper respiratory tract (for example, acid mists, alkalis). Systemic poisons: Produce pathologic reactions in various systems of the body (for example, lead, manganese, cadmium). Allergy-producing: Produce reactions such as itch ing, sneezing and asthma (for example, pollens, isocyanates, gums, spices). Febrile reaction-producing: Produce chills followed by fever (for example, fumes of zinc and copper). Combinations of Gas, Vapor, and Particulate Contaminants Combinations of contaminants may occur simultaneously in the atmosphere. Contaminants may be entire ly different substances (dusts and gases from blasting) or the particulate and vapor forms of the same substance. Synergistic effects (joint action of two or more agents that results in an effect which is greater than the sum of their individual effects) may occur. Such effects may require extraordinary protective measures. NOTE 1: The adverse effects of oxygen deficiency increase with decreasing atmospheric pressure or increased altitude. NOTE 2: Conditions Immediately Dangerous to Life or Health (see Section 2, Definitions) may result from most of the above hazards with the probable exception of nuisance or low toxicity dusts. Such conditions constitute atmospheres that would rapidly lead to death or to injury that would eventually impair health. For example, a ten-minute exposure to 120 parte per million (ppm) of phosgene may be fatal, and exposure to very high concentrations of a radio active material such as plutonium 239 could present a danger to health from delayed effects of radiation damage to body tissues. AM ERICAN NATIO NAL STANDARD PRACTICES r am FOR RESPIRATORY PROTECTION Z88.2 3.7 Medical Limitations. Persons should not be assigned to tasks requiring use of respirators unless it has been determined that they are physically able to perform the work and use the equipment The local physician shall deter* mine what health and physical conditions are pertinent The respirator user's medical status should be reviewed periodically (for instance, annually). 3.3 Approval. Approved or accepted respirators shall be used when they are available (see Sec* tion 6, Selection of Respirators). The respirator furnished shall provide adequate respiratory protection against the particular hazard for which it is designed in accordance with stan* dards established by competent authorities. The U. S. Department of the Interior, Bureau of Mines, and the U. S. Department of Agriculture are recognized as such authorities. (See Ap pendix, Respirator Approval and Acceptance Listings.) Although respirators listed by the U.S. Department of Agriculture continue to be ac ceptable for protection against specified pesti cides, the U. S. Department of the Interior, Bureau of Mines, is the agency now responsible for testing and approving pesticide respirators. 4. Classification of Respiratory Hazards 4.1 Introduction. The purpose of this section is to list and briefly describe various categories of respiratory hazards that might be encountered and which may require use of respirators. The information provides a general background for relating the guidance in subsequent sections to the type of hazard encountered. Management, however, will find it necessary to consult refer ences on industrial hygiene and toxicology and perhaps expert individuals to develop the nec essary comprehensive Information on specific airborne contaminants. Respiratory hazards for the purpose of this standard, are classified as follows: (1) oxygen deficiency (2) gas and vapor contaminants (a) immediately dangerous to life or health (b) not immediately dangerous to life or health (3) particulate contaminants (dust, fog, fume, mist, smoke, and spray) (a) immediately dangerous to life or health (b) not immediately dangerous to life or health (4) combination of gas, vapor, and particu late contaminants (a) immediately dangerous to life or health (b) not immediately dangerous to life or health Respirators may afford some protection against high temperature atmospheres. See 9.4. Further information on the hazards of and use of respirators in high temperatures is presented in a National Fire Protection Association pub lication, Breathing Apparatus for The Fire Service, published in 1966. 4 Classification and Description of Respira tory Hazards. The basic respiratory hazards listed in 4.1 are classified in Table 1 according to expected biological effects of the contami nants. Many respirators, particularly air-puri fying respirators, are designed and selected on the basis of chemical and physical properties of the air contaminants. Therefore, gas, vapor, and particulate contaminants are also presented in Table 2 according to their physical and chemical properties. Particle size distribution and solubility are important parameters for particulate contami nants. Particles smaller than 5 microns in aero dynamic diameter more readily reach the lungs and are more readily dissolved and absorbed into the bloodstream or deposited on lung tissue. The solubility of the material usually deter mines whether the resulting toxic effect, if any, is in the lungs or other organs. Particles larger than 5 microns aerodynamic diameter are gen erally trapped in the upper respiratory tract, cleared, and swallowed with possible subsequent absorption from the gastrointestinal tract, de pending on their solubility. 5. Classification, Description, and Limitations of Respirators 5.1 Introduction. The purpose of this section is to provide a description of the various types of respirators, their limitations, and capabilities, as a background for subsequent sections which discuss their selection, use, and maintenance. Respirators fall into the following general classifications, according to mode of operation: (1) atmosphere-supplying respirators (a) self-contained (b) hose-mask (c) air-line (d) combination self-contained and hosemask or air-line 11 230 Z88.2 AMERICAN NATIONAL STANDARD PRACTICES (2) air-purifying respirators . (a) gaa and vapor (gas mask and chemical cartridge) (b) particulate (dust, tog, fume, mist, smoke, and sprays) - (c) combination gas, vapor, and particu late (3) combination atmosphere-supplying and air-purifying respirators 5.2 Classification, Description and Limita tions of Respirators. This information is pre sented in two tables. Table 3 covers the classi fication and description of respirators according to the general classifications in 5.1. Table 4 covers capabilities and limitations of respirators arranged to correspond to the subject headings in Table 3. More detailed information on specific types of respirators can be obtained from respirator manufacturers and from the Respiratory Protect five Devices Manual published by the American Industrial Hygiene Association and the Ameri can Conference of Governmental Industrial Hygienists in 1963. The canister color code table from American National Standard Identification of Gas Mask Canisters, K13.1-1967, is provided in Table 5. The code indicates the colors assigned to canis ters to identify the types of atmospheric con taminants against which they will protect. 5.3 Respirable Air and Oxygen for Self-Con tained Breathing Apparatus and Hose-Type Respirators. Compressed air, compressed oxy gen, liquid air, and liquid oxygen used for res- Tabie 2 Classification of Respiratory Hazards According to Their Properties which Influence Respirator Selection Cos and Vapor Contaminants Inert: They do not tract with other aubttancea under moat rendition* and create a respiratory hnsard by displacing air and producing oxygon deficiency (for example, helium, neon, argon). Acidic: Suimlancra that are acid* or that react with water tn produce an acid. In water they produce posi- tivrly charged hydrogen ions. They take sour and many are corrosive to tissues (for example, hydrogen chloride, sulfur dioxide, fluorine, nitrogen dioxide, acetic acid, carbon dioxide, hydrogen sulfide, and hydrogen cyanide). . Alkaline: Substances that are alkalies or that react with water to produce an alkali. When in water solu tions, they result in the production of negatively charged hydroxyl ions (OH*). They taste bitter, and many are corrosive to tissues (for example, ammonia, amines, phosphine, arsine, and stibine). Organic: These are the compounds of carbon. Examples are saturated hydrocarbons (methane, ethane, butane), unsaturated hydrocarbons (ethylene, acetylene), alco hols (methyl ulcohol. propyl alcohol), ethers (methyl ether, ethyl ether), aldehydes (formaldehyde), ketones (dimethyl ketone), organic adds (formic add. acetic add), halides (chloroform, carbon tetrachloride), amidos (furmamide. acetamide), nitriles (acetonitrile), isocyanates (toluene diisneyanate), amines (methylamine), epoxies (epoxyethane, propylene oxide), and aromatics (benzene, toluene, xylene). Organomctallic: Compounds in which metals are chemi cally bonded to organic groups (for example, ethyl silicate, tetraethyl lead, and organic phosphates). Hydrides: ComiMmnd* in which hydrogen is chemically bonded to metals and certain other elements (for example, dihnrnne ami lithium hydride). Particulate Contaminants Partidss are produced by mechanical means by the disintegration processes of grinding, crushing, drilling, blasting, and spraying; or by the physiocheraical re actions such aa combustion, vaporisation, distillation, sublimation, calcination, and condensation. Particles are classified os follows: Dust: A solid mechanically produced-particle with sizes varying from subaicroscopie to visible or macroscopic Spray* A liquid mechanically produced particle with sixes generally in the visible or macroscopic range. Fume: A solid condensation particle of extremely small particle size, generally less than one micron in diam eter. Mist: A liquid condensation particle with sizes ranging from submicroscopic to visible or macroscopic Fog: A mist of sufficient concentrate to perceptibly obscure vision. Smoke: A system which includes the products of incom plete combustion of organic substances in the form of solid and liquid particles and gaseous products in air. Smoke is usually of sufficient concentration to percep tibly obscure vision. 12 ' 2>2t FOR RESPIRATORY PROTECTION Z88.2 piration shall be of high purity. Oxygen shall meet the requirements of the United States Pharmacopoeia for medical or breathing oxygen. Breathing air shall meet at least the require* ments of the specification for Grade D breathing air as described in Compressed Gas Association Commodity Specification G-7.1-1966. Compressed oxygen shall not be used in supplied-air respirators or in open-circuit selfcontained breathing apparatus that have pre viously used compressed air. Compressed air might contain low concentrations of oil. When high-pressure oxygen passes through an oil- or grease-coated orifice, an explosion or fire may occur. Breathing air may be supplied to respirators from cylinders or air compressors. Cylinders shall be tested and maintained in accordance with applicable Department of Transportation or Interstate Commerce Commission Specifica tions for shipping containers. Compressors shall be constructed and situated so as to avoid entry of contaminated air into the system and suitable in-line air purifying sorbent beds and filters installed to further assure breathing air quality. A receiver of sufficient capacity to enable the respirator wearer to escape from a contaminated atmosphere in event of compressor failure, and alarms to indicate compressor failure and over hearing shall be installed in the system (see 6.3.2). Air-line couplings shall be incompatible with outlets for other gas systems to prevent inadvertent servicing of air-line respirators with nonrespirable gases or oxygen. Breathing-gas containers shall be marked in accordance with American National Standard Method of Marking Portable Compressed Gas Containers to Identify the Material Contained, Z48.1-1954; Federal Specification BB-A-1034a, June 21, 1968, Air,. Compressed for Breathing Purposes; or Interim Federal Specification GGB-00675b, April 27,1965, Breathing Apparatus, Self-Contained. Further details on sources of compressed air and its safe use will be found in Compressed Gas Association Pamphlet G-71968. 6. Selection of Respirators 6.1 Approved or Accepted Respirators. When ever possible, approved or accepted respirators shall be used. Respirator approval and accept ance tests and listings and selection of other than approved or accepted respirators are dis cussed in the Appendix. 6.2 General Considerations. The multiplicity of hazards that may exist in a given operation requires careful and intelligent respirator selec tion. This selection is made even more complex by the many types of respirators available. Each type has its limitations, areas of application, and operational and maintenance requirements. The selection of a proper respirator for any given situation requires consideration of the following factors: 1) nature of the hazard (see Section 4); 2) extent of the hazard; 3) work re quirements and conditions; and 4) characteris tics and limitations of available respirators (see Section 5). Table 6 is a quick reference guide for the selection of respiratory protection appropriate to the type and degree of hazard. The Table provides minimal guidance, however, and shall be used along with other information, such as that given in this standard and in directions provided by respirator manufacturers. When there is doubt about the concentration of oxygen or hazardous material present in the atmosphere,. only those respirators listed as suitable for respiratory protection against oxy gen deficiency shall be used. Any erring in the selection of respirators shall be on the safe side. 63 Nature of the Hazard. The chemical and physical properties, toxicity, and concentration of the hazardous material shall be considered in respirator selection (see Section 4 for classifica tions and discussion of respiratory hazards). 63.1 Oxygen-Deficient Atmospheres. Only respirators that provide an independent, respira ble atmosphere shall be used in oxygen-deficient atmospheres. Normally, a self-contained breath ing apparatus, hose mask with blower, or air line respirator with auxiliary self-contained air supply is used for this purpose. Air-line respira tors without auxiliary air supply shall be used only with the precautions outlined in 63.2. An attendant shall be standing by at the entrance to the oxygen-deficient atmosphere at all times with proper communications and res cue equipment in case of an emergency. See 7.3 for use of respirators in oxygen-deficient atmo spheres. 633 Immediately Dangerous Atmospheres. If it is probable that atmospheres immediately dangerous to life or health may occur, then both the normally expected inward leakage (see 6.3.3) and the reliability of the respirator shall 13 Table 3 Classification and Description of Respirators by Mode of Operation to AM ERICAN N ATIO N AL STANDARD PRACTICES Atmosphere-Supplying Respirators Afr-PuriXying Respirator* A respirable atmosphere independent of the ambient air la supplied to the Half-mask, full facepiece, or mouthpiece respirator equipped with air-purify wearer. ing units to remove gases, vapors, and particulate matter from the ambient Self-Contained Breathing Apparatus (SCBA) Hose Mask and Air-Line Respirator (1) llos* Mask air prior to ita Inhalation. Some air-purifying respirators are blower-operated and provide respirable air to the facepiece (or hood) under a alight positive pressure. Supply of air, oxygen, or oxygen generating material corded by Equipped with full facepiece, non kinking breathing tube, rugged safety Css- and Vapor-Removing Respirators Particulate-Removing Respirators wearer. Normally equipped with harness and a large diameter heavy- Pocked sorbent beds (cartridge Filter media in pads, cartridges, or full facepiece, but some with a duty nonkinking air supply lions. or canister) remove single gases or canisters remove .dust, fog, fume, mouthpiece for escape purposes. The breathing tube and hose are vapon (for example, chlorine gaa), mist, smoke or spray particles. Fillen (1) Closed-Circuit SCRA (oxygen only) (a) Compressed or liquid oxygen type. High-pressure Os from a gaa securely attached to the harness. A check valve allows airflow only toward the facepiece. The facepiece is fitted with an exhalation valve. a single class of gases or vapors (for example, organic vapors) or a com bination of two or more classes of gases and vapors (for example, acid are designed to remove a single type of particle (silica dust) or dames of particles (duals and fumes). Fillers may be replaceable or a permanent cylinder passes through a high- The harness has provision for attach gases, organic vapon. ammonia, and part of the respirator. Some filters VP pressure reducing valve and, in some designs, through a lowpressure admission valve to a breathing bag or container. Liquid K oxygen it converted to a low- ing a safety line. (a) Hose mask with Mower. Air la supplied by a motor-driven or handoperated blower. The wearer can con tinue to inhale through the hose if carbon monoxide) by absorption, adsorption, chemical reaction or catalysis or a combination of these methods. (1) Full Facepiece Respirator (Cas can be used only once; others are reusable and should be cleaned ac cording to the manufacturer's in structions. (1) Full Facepiece Respirator M vP pressure gaseous oxygen and deliv ered to the breathing bag. The wearer inhales from the bag through a corrugated tuba con nected to a mouthpiece or facepiece ' end a one-way check valve. Exhaled air passes through another check valve and tuba Into a container of carbon dioxide removing chemical and reenters the breathing bag. Moke up Or enters the bag con the blower fails. Up to 300 feet of hose length la permissible. (h) Hose msilc without Mower. The wearer provides motivating force to pull air through the hose. The hose inlet is anchored and fitted with a funnel or like object covered with a fine mesh screen to prevent entrance of coarse particulate matter. Up to 75 feat of hose length ie permissible. Mask) Equipped with a single large chin canister or harness mounted canis ter with breathing tube and inhala tion and exhalation valves. Canis ters come in the "super" size, "in dustrial" size (regular), and chin style. The service life is approxi mately proportional to the canister sise for a given type of canister. Normally equipped with a highefficiency filter canister designed to protect against hazardous particu lates. Equipped with inhalation and exhalation valves. - (2) Hall-Mask Respirator Normally equipped with one or two dust, mist or fume fillers designed to protect against nuisance and low to moderate toxidty dusts, fumes, and tinuously or os the bag deflates (2) Air-Lias Respirator Canisters for protecting against mists, an exhalation valve, and (nor sufficiently to actuate an admission Respirable air is supplied through CO have an indicator or timer that mally) inhalation valves. A knitted valve. A pressure relief system is a small-diameter air-line from a com hows when the canister shall be fabric cover is sometimes worn on provided and a manual bypass pressor or compressed air cylinders. changed. Canisters are marked in dust respirators to decrease discom system ss\d saliva trap may be pro The airline is attached to the wearer bold letters with the contaminant fort. vided depending upon the dealgn. (b) Oxygen-generating type. Water vapor in the exhaled breath reacts with chemical in the canister to release O* to the breathing bag. The wearer inhales from the bag by belt and con be detached rapidly in an emergency. A flow-control valve or orifice is provided to govern the rate of airflow to the wearer. Exhaled air passes to the ambient atmosphere through a valve(s) or opening in the against which they protect and are color coded for quick identification according to the American National Standard Identification of Gas Mask Canisters, K13.M967 (see Table 5). The maximum concentra (3) Mouthpiece Respirator Infrequently used as a particulate respirator. (See Mouthpiece Respir ator, Gas- and Vapor-Removing, in column 3.) through a corrugated tube and one enclosure (facepiece, hood, suit). Up tion in which the canister can be way check valve at the facepiece. to 250 feet of air-line is permissible. safely used U indicated on the label. % FOR RESPIRATORY PROTECTION Exhaled air passes through a ,, (a) Continuous-flow class. Equipped (2) lltil-Miik Respirator (Chemical- second check valve breathing tube with a half-mask or full facepiece, or Cartridge Respirator) assembly into the canister. Tht Oj release rate is governed by the, volume of exhaled air. COj is re-1 moved by the canister fill. (2) Open-Circuit SCBA (compressed air, compressed oxygen, liquid air, or liquid oxygen) (a) Demand type.* The demand valve permits oxygen or air flow only during inhalation. Exhaled breath passes to amblant atmo sphere through a valve (a) in the a helmet (abrasive blasting) or hood covering the wearer's head and neck. At least four cubic feel of air per minute to tight-fitting facepieces and six cubic feet per minute to loose -fitting hoods and helmets shall be. suired. 1 Demand type,* Equippedwith " j|_or lull. " lece. The demand valve permits flow of air only during inhalation. (c) Pressure-demand type-t uipiMd with one or more cart ridge ond exhalation and inlialatlon valves. \3) Mouthpiece Respirator A compact device designed for quids application whan the atmo sphere unexpectedly te contami nated with a hazardous material. Normally consists of a housing with a mouthpiece and a tingle cartridge, a nose damp, exhalation and inha lation valves, and a neckband. facepiece. A bypass system la pro vided in case of regulator failure Equipped with a half-mask or full facepiece. A positive pressure is Combination Css, Vapor, and Fartfculatadlemaving Respirators except on escape-type units. maintained in the facepiece at all 8oma canisters and cartridges contain both filters and sorbents to provide (b) Pressure-demand type-t Equipped with full facepiece only. time#. (3) Supplied Air Suit protection against contaminants. Some filters are designed to be attached to a sorbent cartridge aa a pre-filter (for example, for pidnt spray operation). Jo Positive pressure is maintained In the facepiece at all times. The A form of continuous air-line respirator (see air-line respirator * K> wearer usually has the option of selecting the demand or pressure- above). The suit is one or two piece and of leak-resistant material. Air b -c. to demand mode 0o1f operation. supplied to the rail through a system *. of internal tubes to the head, trunk, ' and extremities. Air exhausts through valves located in appropriate parts of . the suit ' Combination Setf-Contaioed and Alr-Lins Respirators Normally a demand or pressure-demand type air-line respirator with full or half-mask facepiece, together with a small compressed-air cylinder to provide air if the normal supply fails. Wearer Immediately returns to a respirable atmosphere if the normal air supply fails. ' Combination Atmosphere-Supplying and Air-Purifying Respirators These provide the wearer the option of using either of two different modes of operation. They may be an airline respirator with an air-purifying attachment to provide protection In the event the sir supply fails or an air-purifying respirator with a small air cylinder in case the atmosphere unexpectedly exceeds safe conditions lor use of an air-purifying respirator. 'Equipped with a demand valve that is activated on Initiation of inhalation and permita the flow of breathing atmosphere to the facepiece. On --hatatln^ pres sure in the facepiece becomes positivs and the demand valve la deactivated. tA small positive pressure is maintained at all times in the facepiece by a spring-loaded or balanced regulator and exhalation valve. Table 4 Capabilities and Limitations of Respirators ' 'sssss^g...................... .. " " "" :1 ,1 ' j,s sssssssa- Atmosphere-Supplying Rctplrilon Air-Purifying Respirators sss= j AM ERICAN NATIO NAL STANDARD PRACTICES (Sec 5.3 for specification* on respirable atmospheres.) Atmosphere-supplying respirators provide protection against oxygen defi ciency and most toxic atmotphem. The breathing atmosphere is indepen dent of ambient atmospheric conditions. Centra! Limitations] Escept for the supplied-alr suit, no protection is provided against shin irritation by materials such as Ammonia and HCi, or against sorption of materials such as HCN, tritium, or organic phosphate pesticides through the skin. See 6151. Facepieces present special problems to indi viduals required to wear prescription lenses (see 9.1 and 9.2). Self-Contained Breathing Apparatus (SCBA) The wearer carries his own breath ing atmosphere. Use is permissible in atmospheres immediately dan gerous to life or health. Limitations: The period over which the device will provide protection is limited by the amount of air or osygen in the apparatus, die am bient atmospheric pressure (service life is cut in half by a doubling of the atmospheric pressure), and work load. A warning device shall be provided to indicate to the wearer when the service life has been reduced to a low level. Some SCBA device* have a short service life (few minutes) and are suitable only for escape (self-rescue) from an irrespirable atmosphere. Chief limitations of SCBA devices ere their weight or bulk or both, limited service life, and the training re quired for their maintenance and_ safe use. (I) Closed-circuit SCBA The closed circuit operation con serves osygen and permits longer service life. Hose Mask or Air-line Respirator The respirable air supply is not limited to the quantity the individual can carry, and the devices are light weight and simple. Limitations: The wearer is restricted in movement by the hose or air-line and must return to a respirable atmosphere by retracing his route of entry. The hose or air-line is subject to being severed or pinched oil. (1) Hose Mask (a) llose mask with Mower, If the blower fails, the unit still provides protection, although a negative pres sure exists in the facepiece during inhalation. Use is permissible in atmospheres immediately dangerous to life or health. (b) Hose mask without Mower. Limited to use in atmospheres from which the wearer can escape un harmed without aid of the respirator. (2) Air-Line Respirators (ContinuousFlow, Demand and Pressure-Demand Types) The demand type produces a nega tive pressure in the facepiece on inhalation whereas continuous flow and pressure-demand types maintain Ccneral Umhaltonsi Air-purifying respirators do not protect against oxygen- deficient atmospheres nor against skin irritation by, or sorption through the skin of, airborne contaminants. See 6.3.1. and 6.3.5.L The maximum contaminant concentration against which an air purifying respirator will protect is determined by the designed efficiency and capacity of the cartridge, canister, or filter. For gases and vapors and for particles having a TLV of less than 0.1 mg/m*. the maximum concentration for which the air purifying unit is designed is specified on the label. Respirators without a blower to maintain a constant positive pressure within the facepiece will not provide the maximum design protection specified unless the facepiece is care fully fitted to the wearer's face to prevent inward leakage. See 7.5. The time period over which protection is provided b dependent on canister, cartridge, or Alter type, concentration of contaminant, and the wearer's respiratory rate. The proper type of canister, cartridge, or Alter shall be selected for the particular atmosphere and conditions. Air-purifying respirators generally causa discomfort and objectionable resistance to breathing although these problems are minimised in Mower-operated units. Respirator facepieces pre sent special problems to individuals required to wear prescription lenses. (See 9.1 and 9.2.) These devices do have the advantage of being small, light, and simple in operation. Css- and Vapor-Removing Respirators Additional Limitations: No protec tion b provided against particulate contaminants, unleu specified on canister or cartridge label. A rise in canister or cartridge temperature indicates that a gas or vapor is being removed from the inspired air. This is not a reliable indicator of canister performance. An uncom fortably high temperature indicates a high concentration of gas or vapor and requires an immediate return ' to fresh air. PartIculate-Removing Respirators Additional Limitations: Protect against nonvolatile particles only. No protection against gases and vapors. The filter shall be replaced or cleaned when breathing becomes difficult due to plugging by retained particles. These respirators shall not be used during shot and sand blasting opera, tions. Abrasive-Muting respirators shall be used. (1) Full Facepiece Respirator (Cu Mask) Should avoid use in atmospheres immediately dangerous to life or health if the contaminant (s) lacks sufficient warning properties (that b, odor or irritation). (I) Full Facepiece Respirator Should avoid use in atmospheres immediately dangerous to life or health if die contaminant (s) lacks sufficient warning properties (that b, odor or irritation). * FOR RESPIRATORY PROTECTION JC t (2) Open-circuit SCBA--demand and lireiiurc-deroand The demand type producea negative pressure in (he facepiece on inhalation whereas the pressure- ' demand type maintains a positive pressure in the facepiece and is leas, apt to permit inward leakage of contaminants. a positive pressure in the facepiece at all times and are less apt to iiermit inward leakage of contaminants. Limitations: Air-line respirators are limited to use in atmospheres not immediately dangerous to life or health except under conditions speci fied in 612 and 7.3. Air-line respira tors provide no protection if the air sup|ily fails. (3) Supplicd-Air Suit These suits protect against atmo spheres that affect the skin or mucous membranes or that may be absorbed through the unbroken akin. Limitations: Some contaminants, such as tritium, may penetrate the suit material mid limit its effective ness. Other contaminants, such as fluorine, may react chemically with the suit materia) and damage it. See 6.3.S.I. These suits are limited in use to atmospheres not immediately danger ous to life or health except under the conditions specified in 63.2 and 7.3. (2) Half-Mask Respirator (Chemical* Cartridge Respirator) Shall not use in atmospheres im mediately dangerous to life or health and should bo limited to low concentrations of gases and vapors. A fabric covering shall not be worn on the facepiece since it will permit gases and vapors to pass. No protection is provided to the eyes. (3) Mouthpiece Respirator (Chemical Cartridge) Shall not be used in atmospheres immediately dangerous to life or health. Mouth breathing prevents detection of contaminants by odor. The nose dip shall be securely in place to prevent nasal breathing. No protection is provided to the eyes. (4) Self-Rescue Mouthpiece Respira tor Designed for setf-reacue from im mediately dangerous atmospheres of gases and vapors. Mouth breath ing prevents detection of contam inants by odor. The nose dip shall be sccurdy in place to prevent nasal breathing. No protection is provided to the eyes. (2) Half-Mask Respirator Shall not bo used in atmospheres immediately dangerous to Ufa or health. A fabric covering on the face piece is permissible only in atmo spheres of coarse dusts and mists of low toxidty. No protection is provided to the eyes. (3) Mouthpiece Respirator (Filter) Shall not bo used in atmospheres immcdiatdy dangerous to life or health. Mouth breathing prevents detection of contaminants by odor. The noss dip shall be securely in place to prevent nasal breathing. No protection is provided to the eyes from irritating aerosols. (4) Self-Rescue Mouthpiece Respirator (Filter) Designed for self-rescue from atmospheres having immediately dangerous concentrations of toxic particles. Mouth breathing prevents detection of contaminants by odor. The nose dip shall be securely in place to prevent nasal breathing. No protection is provided to the eyes from irritating aerosols. Combination Self-Contained and Air-Line Respirators The equipping of an air-line respirator with a small cylinder of compressed air to provide an emergency air supply qualifies the respirator for use in immediately dangerous atmospheres. See 6.3.2. Combination Particulate and Vapor- and Css-Removing Respirators The advantages and disadvantages of the component parts of the combination respirator as described above will apply. Combination Atmosphere-Supplying and Air-Purifying Respirators The advantages and disadvantages, expressed above, of the mode of operation being used will govern. The mode with the greater limitations (air-purifying mode) will mainly determine the overall capabilities and limitations of Ihs respirator since the wearer may for some reason fail to change the mode of opera tion even though conditions would require such change. g Z88.2 AMERICAN NATIONAL STANDARD PRACTICES be given full consideration. In oxygen-deficient atmospheres with no toxic materials, inward leakage is normally not a problem unless the leakage exceeds a few percent It is essential that in highly toxic atmospheres, inward leak age, if any, be minute. See &3.2.1 and 7.3 for use of respirators in immediately dangerous at mospheres. 6.&2.1 Respirators Recommended for Im mediately Dangerous Atmospheres. The U. S. Bureau of Mines and responsible industrial hy giene and safety organizations recommend the following respirators, listed in decreasing order with regard to the protection they offer the wearer, for use in atmospheres immediately dan gerous to life or health. These atmospheres in clude those which are oxygen deficient or where high concentrations of gases or vapors exist: (1) pressure-demand open-circuit or pres sure-type closed-circuit self-contained breathing apparatus (2) combination pressure-demand air-line res pirator with auxiliary self-contained air supply (3) combination constant-flow air-line res pirator with auxiliary self-contained air supply Table 5 Color Code for Gas-Mask Canisters (ANSI K1U-1967) Atmospheric Contaminants to bo Protected Against Acid gases Hydrocyanic add gss Chlorine gas Colors Assigned* White White with %-inch green stripe completely around the canister near the bottom White with V^ioch yelloto stripe completely around the canister near the bottom Organic vapors Black Ammonia gas Grceo Acid gases and ammonia gas Carbon monoxide Acid gases and organic vapors Hydrocyanic add gas and chloropieria vapor Acid gases, organic vapors, and ammonia gaaes Green with &inch white stripe completely around the canister near the bottom Blue YeQow Yellow with V&*inch blue stripe completely round the eanister near the bottom Brown Radioactive materials, except ing tritium and noble genes Purple (Magenta) Particulates (dusts, fumes, mists, fogs, or smokes) in combination with any of the above gases or vapors Canister color for contaminant, as designated above, with %-ineh gray stripe completely aronnd the eanister near the top AU of the above atmospheric contaminants Red with %-ineh gray stripe completely around the canister near the top M.riy" sLh. a.l1l n"u"t VUr uiiiwii a__s ithle. main color for a caniater designed to remove acids or vapors. NO'I'K: Oranar shall hr used as a complete body, or stripe color to represent [taut not included in this table. The user Mill need to refer to the eanister label to determine the degree of protection the canister will afford. 18 30/7 'for respiratory protection (4) demand-flow open-circuit or closed-circuit self-contained breathing apparatus (where there may be a negative pressure in the breathing system at any time) (5) combination demand-flow air-line res pirator with auxiliary self-contained air supply (6) hose mask with blower When self-contained breathing apparatus or hose masks with blowers are used in atmo spheres immediately dangerous to life or health, standby men must be present with suitable res cue equipment 6.3.2.2 Other Respirators Which May Be Used under Certain Conditions in Atmospheres Immediately Dangerous to Life or Health. Air line respirators are not approved or recom mended for use in immediately dangerous at mospheres because no respiratory protection is provided if the air supply fails. However, if Z88.2 routine protection or operational designs pre clude use of the recommended types of respira tors which workers should wear, the following air-line respirators may be considered, provided an adequate flow of respirable air is maintained. These are listed in decreasing order with regard to the protection they provide for the wearer. (1) pressure-demand air-line respirator with full facepiece (2) continuous-flow air-line respirator with full facepiece, helmet, hood, or suit (3) demand-flow air-line respirator with full facepiece (4) pressure-demand air-line respirator with half-mask facepiece (only for atmospheres that do not cause eye irritation or injury) (5) continuous-flow air-line respirator with half-mask facepiece (only for atmospheres that do not cause eye irritation or injury) Table 6 Guide for Selection of Respirators Hazard Respirator (See Note 1.) Oxygen Deficiency Self-contained breathing apparatus. Hose mask with blower. Combination air-iine respirator with auxiliary self-contained air supply or an air-storage receiver with alarm. Gas and Vapor Contaminants Immediately dangerous to life or health. (See Note 2) Self-contained breathing apparatus. Hose mask with blower. Air-purifying, full facepiece respirator with chemical canister (gas mask). Setf-rescue mouthpiece respirator (for escape only). Combination air-line respirator with auxiliary self-contained air supply or an air-storage receiver with alarm. Not Immediately dangerous to life or health. Air-line respirator. Hose mask without blower. Air-purifying, half-mask or mouthpiece respirator with chemical cartridge. Particulate Contaminants - Immediately dangerous to life or health. (See Note 24 Self-contained breathing apparatus. Hose mask with blower. Air-purifying, full facepiece respirator with appropriate filter. Self-rescue mouthpiece respirator (for escape only). Combination air-line respirator with auxiliary self-contained air supply or an air-storage receiver with alarm. . Not immediately dangerous to life or health. Air-purifying, half-mask or mouthpiece respirator with (liter pad or eanridge. Air-line respirator. Air-tine abrasive-blasting respirator. Hose mask without blower. Combination gas, vapor, and particulate contaminants Immediately dangerous to life or health. (See Note 2.) Self-contained breathing apparatus. Hose mask with blower. Air-purifying, full facepiece respirator with chemical canister end appropriate filter (gas mask with filter). Self-rescue mouthpiece respirator (for escape only). Combination air-tine respirator with auxiliary self-contained air supply or an air-storage receiver with alarm. Not immediately dangerous to life or health. Alr-llne respirator. , Hose mask without blower. Air-purifying, half-mask or mouthpiece respirator with chemical cartridge and appro priate filter. . NOTE 1: For details on descriptions, capabilities, and limitations of respirators, refer to Tables 3 and 4. NOTE 2: For details on use ol respirators In hazardous atmospheres, see 6.3.2 and 7.3. 19  3W8.2 AMERICAN NATIONAL STANDARD PRACTICES (6) demand-flow air-line respirator with half mask facepiece (only for atmospheres that do not cause eve irritation or injury) Pressure-demand or continuous-flow air-line respirators with full facepiece provide the wearer with a degree of respiratory protection equal to that afforded by a positive pressure self-con tained breathing apparatus as long as an ade quate flow of respirable air is maintained. Also, a demand-flow air-line respirator with full face piece would be equivalent to a demand-flow open-circuit or closed-circuit self-contained breathing apparatus as long os an adequate supply of respirable air is maintained. Persons using air-line respirators in atmo spheres immediately hazardous to life or health shall be equipped icith safety harnesses and safety tines for lifting or removing persons from hazardous atmospheres or other and equivalent provisions for the rescue of persons from haz ardous atmospheres shall be used. A standby man or men with suitable self-contained breath ing apparatus shall be at the nearest fresh air base for emergency rescue. Before a person is permitted to wear an air line respirator in a hazardous atmosphere, an industrial hygiene, health physics, or safety en gineering department representative or a qual ified industrial hygienist, health physicist, or safety engineer shall be responsible for com pliance with the following: (1) Air-line hose from a compressor or cylin der air supply shall be protected from damage, including cutting, kinking, crushing, or burning. In some cases an armored hose shall be used. Hose couplings shall be protected against dis connection. Trailing air-line hose shall be ar ranged to minimize tripping and to permit ready escape. (2) The cylinder containing the air supply for an air-line respirator shall be tested for oxy gen concentration and carbon monoxide content and shall lie respirable. All air shall meet the minimum specification for Type I, Grade D gaseous air of the Compressed Gas Association Commodity Specification for Air, G-7.1-1966. The air supply in the cylinder shall be adequate for completion of the work and escape. Oxygen must never be used with air-line respirators. (2) The compressor for supplying air shall lie equipped with necessary safety and standby device*. A breathing air-type compressor shall bo used. An air-storage receiver shall also be provided to furnish the wearer with an adequate supply of escape air if the compressor fails to operate. A compressor shutoff alarm and nec essary aerosol and vapor and gas filters shall also be incorporated into the system. If an oil-lubricated compressor is used, it shall have a high-temperature or carbon monox ide alarm, or both. If only a high-temperature alarm is used, the air from the compressor shall be frequently tested for carbon monoxide to in sure that it meets the specifications in 6.3.2.2 (2). (4) The wearer shall be properly trained in the use of the air-line respirator and shall be well-informed of the hazard. A standard operat ing procedure shall be prepared for each situa tion for which air-line respirators are employed in atmospheres immediately hazardous to life or health, and air-line respirator users shall be thoroughly familiar with this procedure. (5) Continuous-flow air-line respirators are designed for maximum comfort with a minimum airflow that will adequately protect the wearer in a non-hazardous atmosphere. However, they are capable of providing adequate airflow to protect the wearer in a hazardous atmosphere. This adequate airflow is obtained when the air flow control valve is fully open. The recommended minimum airflows for use of air-line respirators in hazardous atmospheres are five cubic feet per minute to tight fitting facepieces and seven cubic feet per minute to loose fitting hoods or helmets. Persons wearing supplied-air suits shall follow the manufacturer's instructions concerning minimum airflow. For further information on furnishing com pressed air to air-line respirators, refer to Com pressed Gas Association Pamphlet G-7-1968. See 7.3 concerning safe procedures during use of respirators in atmospheres immediately danger ous to life or health. BJSJi Not Immediately Dangerous Atmo spheres. If immediately dangerous atmospheres are not present or will not occur, then the con sequences of respirator failure are lessened and emphasis can be placed on other factors such as long term protection, convenience, cost, com fort, and wearer acceptance. These factors should he weighed one against another since they are not always compatible. However, long term protection should be given priority over all other factors. 20 FOR RESPIRATORY PROTECTION Z88.2 Long teim protection is determined primarily by the amount of inward leakage of atmospheric contaminants during normal usage of the res pirator. The various types of respirators are groupud below according to the increasing amount of inward leakage one might expect during their routine use. Group I Supplicd-air suit Pressure-demand full facepiece open-circuit and air-line devices . Pressure-type full facepiece closed-circuit self- contained breathing apparatus Continuous-flow full facepiece air-line respirator Air-line respirator with loose-fitting hood gath ered around the waist Hose-mask with blower and full facepiece mask Group 2 Demand-type full facepiece open-circuit selfcontained breathing apparatus Demand-type full facepiece air-line respirator Pressure-demand half-mask air-line respirator Group 3 . Continuous-flow half-mask air-line respirator Demand-type half-mask air-line respirator Air-line respirator with loose-fitting hood gath ered around the neck Group 4 Air-purifying respirator with blower and with full facepiece or hood gathered around the waist Group 5 Air-purifying respirator with blower and with half-mask facepiece or hood gathered around the neck Group 6 Hose mask'without blower Air-purifying full facepiece respirator without blower Group 7 Air-purifying half-mask respirator without blower Mouthpiece respirator The negative pressure produced in the face piece of many respirators (some in Groups 2 and 3 and all in Groups 6 and 7) during inhala tion will cause inward leakage of ambient air if leaks exist. The amount of inward leakage ex pected for various types of respirators is vaguely understood and is related to the faccpiece-toface seal and leakage of various components in cluding air-purifying units. For Group 1, in ward leakage will normally be infinitesimal or nonexistent For Groups 2, 3. 4, and 5, inward leakage will normally be minute. In Group 6, inward leakage with a good facepiece-to-face seal and with ideal wearing conditions may be as'low as 0.1 percent In practice, however, this low level leakage is usually not attained due to poor facepiece-to-face fit and adverse wearing conditions such as face movements and beard growth. For Group 7, inward leakage with good facepiece-to-face fit and ideal wearing condi tions may be as low as 1 percent. This leakage level, however, is seldom attained for reasons similar to those cited for devices in Group 6. It is, therefore, important (particularly for devices in Groups 6 and 7) that due consideration be given to potential inward leakage in selecting devices. Experience has demonstrated that not all persons can obtain a satisfactory facepiece-toface seal with a single full facepiece or half-mask air-purifying respirator. Therefore, to provide an adequate facepiece-to-face seal on a variety of facial features, it may be necessary that two or more models of full facepiece or half-mask respirators be available. When an individual can be fitted with two or more respirators, he should be permitted to select the most comfortable device. See 7.5 for a discussion of face fit tests and procedures. 63.4 Monitoring of Air Contaminants. Eval uation of contaminant concentration to which a person wearing a respirator may be exposed is an integral part of an effective respirator pro gram. Air sampling data are important in the selection of the proper respirator and should include: 1) identification of the contaminant; 2) nature of the hazard; and 3) concentration at the breathing zone. The data are also helpful in estimating the possible levels of exposure that may have occurred during use of respirators. In an air monitoring program, sampling should be carried out over at least one cycle of operation and, preferably, over several cycles when production activity varies. Normally, samples should be collected at the worker's breathing zone. However, where necessary, gen eral air samples should be collected in the vicinity of the operation. The sampling period will be determined by the sensitivity of the analytical method and the acceptable contami nant concentration. It is important that representative samples be obtained. The number of samples to lie taken depends on the variation in contaminant 21 220 ZH8.2 AMERICAN NATIONAL STANDARD PRACTICES generation rate during the operation. Sampling data should permit estimation of the worker's time weighted exposure. The peak contaminant concentration should also be estimated to as sure that the respirator selected will provide adequate protection against high transient air concentrations. Breathing zone sampling is important since significant variations in concentrations are noted between general air and the worker's breathing zone. Use of personal or lapel air samplers is encouraged since they have been shown to more closely identify the true exposure. Although it is recognized that in emergency situations air sampting cannot be carried out as outlined above, every reasonable elTort shall be made to evaluate conditions of exposure and to provide appropriate respiratory protection. Where a high hazard potential exists, a conserv ative estimate should be made. SJL1 Unusual Hazards. Unusual factors can add new dimensions to a hazardous situation and should be anticipated in selecting respira tors. Some examples are provided here. 6.3JS.1 Absorption through or Irritation of the Skin. Some airborne contaminants are ex tremely irritating to the skin (for example, ammonia and hydrochloric acid) while others are capablu of being absorbed through the skin and into the blood stream with serious, possibly fatal, results. Hydrocyanic acid gas and many of the organic phosphate pesticides, such as parathion, malathion, and tetraethyl-pyrophosphate (TEPP), will penetrate the unbroken skin. A facepiece or hood respirator will not afTord com plete protection against these contaminants. If the concentration- is high, or if exposure is pro longed, a full body-covering suit of impermeable material shall be wom with respiratory protec tion. A facepiece may not be required if the suit is leakproof and adequately ventilated. 6.3Ji.2 Radiation of Skin and Whole Body. Thu respirator may not protect the skin or whole body against radiation from airborne con centrations of certain radionuclides including noble gas radionuclides and other relatively bio logically inert gases. 6.1 Extent and Location of Hazard. The ex tent of the hazard in space and time and its physical location shall be considered in respira tor selection. They include the length of time protection will be needed, entry and exit times, accessibility of a fresh air supply, and the ability to use air lines or move about freely while wear ing the respirator. The location of the contaminated area in respect to a possible source of respirable air requires special consideration. In using a hose mask, air-line respirator, or abrasive-blasting respirator, the distance that the wearer can go into a contaminated atmosphere is limited by the length of hose connected to the source of respirable air. Furthermore, the presence of the hose requires that he enter and leave the area by the same route unless the device is equipped with an auxiliary air cylinder, chemical canister or cartridge, or particulate filter appropriate for use in withdrawal. While wearing a self-con tained breathing apparatus or a gas mask, a person may leave the contaminated area by any exit, but he should make certain that the device will afford protection until he reaches respirable air, taking into account possible delays. 615 Work Requirements and Conditions 6.5.1 Work Time. Work time usually deter mines the length of time for which respiratory protection is needed, including the time neces sary to enter and leave a contaminated area. A self-contained breathing apparatus, gas mask, or chemical-cartridge respirator provide respira tory protection for relatively short periods, whereas the hose mask with blower, air-line respirator, and abrasive-blasting respirator pro vide protection for as long as the facepiece is supplied with adequate respirable air. Particu late-filter respirators can provide protection for long periods, without need for filter replacement, only if the atmospheric particulate loading is low. Therefore, for protracted periods of use, the hose mask with blower and air-line respira tors offer definite advantages. They also cause less discomfort than air-purifying respirators. Some respirators have a means for indicating the remaining service life. Some type of warning is available for all self-contained breathing ap paratus and some gas masks. This may be a pressure gage, timer, audible or physical alarm, or window indicator in the canister. The user should understand the operation and limitations of each type of warning device. Most other gas masks and chemical-cartridge respirators have no indicator of remaining service life. Canisters and cartridges should be changed according to the manufacturer's directions. 6.5.2 Activity of Wearer. The work area to be covered, work rate, and mobility required of 22 331 FOR RESPIRATORY PROTECTION ZS8.2 the wearer in carrying out his work should be selection. The wearer's acceptance of a particu considered in respirator selection. lar respirator depends on the lack of facepiece Air-purifying respirators present minimal in* discomfort, interference with vision, weight of terfcrencc with the wearer's movement Sup* the device, breathing resistance, and individual plied*air respirators with trailing hoses severely physical condition and psychological factors. restrict the area the wearer can cover and pre The ability to form a good facepiece-to-face seal sent a potential hazard where the trailing hose depends on respirator design and facial features, can come in contact with machinery. Self-con and is usually the most important factor in tained breathing apparatus present a size and obtaining proper protection with an air-puri weight penalty which may restrict climbing and fying respirator, particularly of the half-mask movement in tight places. type. See 7.5 for a discussion of face-fit tests The wearer's work rate determines his res and procedures. piratory minute volume, maximum inspiratory flow rate, and inhalation and exhalation breath ing resistance. The respiratory minute volume is of great significance in self-contained and air line respirators^jjperated fi'om cylinders since it determmes-tHeir operating life. Useful der moderate work conditions may be one-t ft under rest conditions. Peak airflow rate is important in the use of constant-flow air-line equipment. The air-supply 7. Use of Respirators 7.1 Operating Procedures. Standard proced ures shall be developed for respirator use. These should include all information and guidance necessary for their proper selection, use, and care. Possible emergency and routine uses of respirators should be anticipated and planned rate should always be greater than the peak for. inspiratory flow rate to maintain the respiratory enclosure under positive pressure. High breathing resistance of air'purify jirators under conditions of heavy can rigiiTrift-.44tiwpd hmntKini 6JIL3 Vision. All facepieces will restrict, to 7.2 Issuance of Respirators. The correct res pirator shall be specified for each job. The res pirator type is usually specified in the work pro cedures by a qualified individual supervising the respiratory protective program. The individual issuing them shall be adequately instructed some degree, the wearer's vision. This may in crease accident potential. Other problems in to insure that the correct respirator is issued. Each respirator permanently assigned to an clude wearing of prescription glasses and fogging individual should be durably marked to indicate of the respirator lens (see 9.1, 9.2, and 9.3). to whom it was assigned. This mark shall not 6J5.4 Communications. Effective speech com affect the respirator performance in any way. munication may be required in jobs for which The date of issuance should be recorded. the respirator is being selected. Section 9.5 pro vides information in this subject. &5J> Temperature Extremes. The ability to cope with stress caused by temperature ex 12 Use in Dangerous Atmospheres. Written procedures shall be prepared covering safe use of respirators in dangerous atmospheres that might be encountered in normal operations or tremes is especially important in emergency situations when only immediately available res pirators can be used. See 9.3 and 9.4 for further in emergencies. Personnel shall be familiar with these procedures and the available respirators. In areas where the wearer, with failure of the details on use of respirators in temperature ex tremes. respirator, could be overcome by a toxic or oxygen-deficient atmosphere, at least one addi 6.5.6 Eye Protection. Where required, full- tional man shall be present Communications facepiece respirator eyepieces and eye protection (visual, voice, or signal line) shall be maintained worn with half-mask facepieces shall meet the between both or all individuals present Plan pertinent requirements of American National ning shall be such that one individual will be Standard Practice for Occupational and Educa unaffected by any likely incident and have the tional Eye and Face Protection, Z87.1-1968. proper rescue equipment to be able to assist the other(s) in case of emergency. See 6.3.1 and o 6.6 Employee Acceptance and Face Fit. These factors are of prime importance in respirator 6.3.2 for guidance on selection of respirators for use in dangerous atmospheres. 23 3lX .238.2 AMERICAN NATIONAL STANDARD PRACTICES 7.1 Training and Education in Proper Use. following the manufacturer's facepiece-fitting For safe use of any respirator, it is essential that instructions such as these two simple field tests: r the user be properly instructed in its selection, use, and maintenance. Both supervisors and workers shall be so instructed by competent persons. Minimum training shall include the following: (1) Positive Pressure Test Close the exhala tion valve and exhale gently into the facepiece. The face fit is considered satisfactory if a slight poeitive pressure can be built up inside the face piece without any evidence of outward teakage (1) Instruction in the nature of the hazard, of air at the seal. For most respirators, this whether acute, chronic, or both, and an honest method of leak testing requires that the wearer appraisal of what may happen if the respirator first remove the exhalation valve cover and then is not used. carefully replace it after the test. (2) Explanation of why more positive con trol is not immediately feasible. This shall in clude recognition that every reasonable effort is being made to reduce or eliminate the need for respirators. (3) A discussion of why this is the proper type of respirator for the particular purpose. (2) Negative Pressure Test Close off the inlet opening of the canister or cartridge(s) by covering with the palm of the hand(s) or by replacing the seal(s), inhale gently so that the facepiece collapses slightly, and hold the breath for ten seconds. If the facepiece remains in its slightly collapsed condition and no inward (4) A discussion of the respirator's capabil ities and limitations. (5) Instruction and training in actual use of the respirator (especially a respirator for emergency use) and dose and frequent super vision to assure that it continues to be properly used. . (6) Classroom and field training to recog nize and cope with emergency situations. leakage of air is detected, the tightness of the respirator is probably satisfactory. Potential users of respirators should also be required to test their facepiece fit by wearing the respirator under realistic test conditions. A concentration of 100 parts per million isoamyl acetate vapor (obtained by vaporizing 17.3 milli liters of isoamyl acetate for each 1,000 cubic feet of room volume) may be prepared in a special chamber, a small plastic enclosure, or in a vacant (7) Other special training as needed for spe cial use. Training shall provide the men an oppor tunity to handle the respirator, have it fitted properly, test its facepiecc-to-face seal, wear it in normal air for a long familiarity period, and, finally, to wear it in a test atmosphere. 7.5 Facepiece Fit Tests and Procedures. Every respirator wearer shall receive fitting in structions including demonstrations and prac tice in how the respirator should be worn, how to adjust it, and how to determine if it fits properly. Respirators shall not be worn when room. If the person wearing the respirator can enter and remain in this testatmosphere without detecting the odor of isamyl acetate, he has a good fit If he detects the odor, he should retreat to fresh air, readjust the facepiece, and repeat the test If leakage is still noted, it can be concluded that this particular respirator will not protect the wearer. The wearer should not continue to tighten the headband straps until they are un comfortably tight simply to achieve a gas-tight face fit If fitted too tightly, the wearer will not wear the respirator or will wear it fitting com fortably loose and will not have a gas-tight seal. Particulate-filter respirators can frequently conditions prevent a good face seal. Such con ditions may be a growth of beard, sideburns, a be adapted for use with chemical cartridges and may also be tested for face fit in isoamyl acetate. skull cap that projects under the facepiece, or To check the fit of a respirator equipped with temple pieces on glasses. Also, the absence of a high-efficiency particulate filter, on irritant one or both dentures can seriously affect the fit of a facepiece. The worker's diligence in ob smoke tube (gloss tube 12 centimeters long by 1 centimeter diameter, filled with stannic chlor serving these factors shall be evaluated by ide-impregnated pumice) produces a very periodic checks. irritating smoke when air is blown through it To assure proper protection, the facepiece fit The smoke is directed at the facepiece seal and shall be checked by the wearer each time he leakage is indicated by irritation of the throat puts on the respirator. This may be done by and lungs. (When testing half-mask facepieces, 24 FOR RESPIRATORY PROTECTION Z88.Z do not direct the smoke into the eyes and in* struct the wearer to keep his eyes dosed during the test.) Freshly produced smoke particles Irom this tube range from less than 0.1 to 3 mi* crons in diameter. The glass tube is scored at each end for cosy breaking. A squeeze bulb with a short rubber tube aspirates air through the tube; visible smoke is immediately formed by contact with moisture in the air. The irritant is hydrochloric acid absorbed on the particulate. A similar smoke is produced with a sulfur trioxide or titanium tetrachloride tube. Several methods of determining facepiece fit are described in detail in the Respiratory Proteetive Devices Manual, published by the Amer* ican Industrial Hygiene Association and the American Conference of Governmental Indus* trial Hygienists in 1963. 8. Maintenance and Care of Respirators 8.1 General. A program for maintenance and care of respirators shall be adjusted to the type of plant, working conditions, and hazards in* volvcd, and shall include the following basic services: (1) inspection for defects (including a leak check) (2) cleaning and disinfecting (3) repair (4) storage Equipment shall be properly maintained to retain its original effectiveness. 82 Inspection. All respirators shall be inspected routinely before and after each use. A respirator that is not routinely used but is kept ready for emergency use shall be inspected after each use and at least monthly to assure that it is in satis factory working condition. Self-contained breathing apparatus shall be inspected monthly. Air and oxygen cylinders shall be fully charged according to the manu facturer's instructions. It shall be determined that the regulator and warning devices function properly. . Respirator inspection shall include a check of the tightness of connections and the condition of the facepiece, headbands, valves, connecting tube, and canisters. Rubber or elastomer parts shall be inspected for pliability and signs of de* terioration. Stretching and manipulating rubber or elastomer parts with a massaging action will keep them pliable and flexible and prevent them from taking a set during storage. A record shall be kept of inspection dates and findings for respirators maintained for emer gency use. 8J3 Cleaning and Disinfection. Routinely used respirators shall be collected, cleaned, and dis infected as frequently as necessary to insure that proper protection is provided for the wearer. Each worker should be briefed on the cleaning procedure and be assured that he will always receive a clean and disinfected respira tor. Such assurances are of greatest significance when respirators are not individually assigned to workers. Respirators maintained for emer gency use shall be cleaned and disinfected after each use. The following procedure is recommended for cleaning and disinfecting respirators: (1) Remove any filters, cartridges, or canis ters. (2) ' Wash* facepiece and breathing tube in cleaner-disinfectant or detergent solution (see following paragraphs). Use a hand brush to fa cilitate removal of dirt (3) Rinse completely in clean, warm water. (4) Air dry in a clean area. (5) Clean other respirator parts as recom mended by manufacturer. (6) Inspect valves, headstraps, and other parts; replace with new parts if defective. (7) Insert new filters, cartridges, or canis ters; make sure seat is tight (8) Place in plastic bag or container for stor age. Cleaner-disinfectant solutions are available that effectively clean the respirator and contain a bactericidal agent The bactericidal agent is generally a quaternary ammonium compound. The respirator may be immersed in the solution, rinsed in clean, warm water, and air dried. Alternatively, respirators may be washed in a liquid detergent solution, then immersed in: 1) a hypochlorite solution (50 parts per mil lion of chlorine) for 2 minutes; 2) an aqueous iodine solution (50 parts per million of iodine) for 2 minutes; or 3) a quaternary ammonium solution (200 parts per million of qunrtcrnary ammonium compounds in water with less than 500 parts per million total hardness). 25 3M *' 308.2 AMERICAN NATIONAL STANDARD PRACTICES Different concentrations of quaternary am monium salts are required to achieve a disin fectinc solution with waters of varying hardness. Also, dermatitis may occur if the quaternary ammonium compounds are not completely rinsed from the respirator. The hypochlorite and iodine solutions are not stable; they age rubber parts, and arc corrosive to metallic parts. There fore, immersion times should not be extended and the disinfectants shall be thoroughly rinsed from the respirator parts. Strong cleaning and disinfecting agents can damage respirator parts. Temperatures above . 185 degrees Fahrenheit and vigorous mechanical agitation should not be used. Solvents which affect elastomer or rubber parts should be used with caution. Respirators may be contaminated with toxic materials (that is, organic phosphate pecticides and radionuclides). If the contamination is light, normal cleaning procedures should provide satisfactory decontamination; if heavy, a sepa rate decontamination step may be required be fore cleaning. For complete decontamination against phos phate pesticides, the respirator should be washer! with alkaline soap and rinsed with 50 percent alcohol (ethyl or isopropyl). Respirators used to protect against radioac tive contaminants should be decontaminated to levels not exceeding 100 disintegrations per min ute per 100 square centimeters fixed alpha and 0.2 millimd per hour of beta-gamma above background at contact There should be no detectable removable activity using standard swipe techniques. 8.1 Repair. Replacement or repairs shall.be done only by experienced persons with parts designed for the respirator. No attempt shall he made to replace components or to make ad justment or repairs beyond the manufacturer's recommendations. Reducing or admission valves or regulators shall he returned to the manufac turer or to a trained technician for adjustment or repair. 8.5 Storage. After inspection, cleaning, and necessary repair, respirators shall he stored to protect against dust, sunlight, heat, extreme cold, excessive moisture or damaging chemicals. Respirators placed at stations and work areas for emergency use should he stored in compart ments built for the purpose, be quickly acces sible at all times, and be clearly marked. Rou tinely used respirators, such as dust respirators, may be placed in plastic bags. Respirators should not be stored in such places as lockers or tool boxes unless they are in carrying coses or cartons. Respirators should be packed or stored so that the facepiece and exhalation valve will rest in a normal position and function will not be impaired by the elastomer setting in an ab- . normal position. Instructions for proper storage of emergency respirators, such as gas masks and self-contained breathing apparatus, are found in "use and care" instructions usually mounted inside the carrying case lid. 9. Special Problems 9.1 Corrective Lens with Full Facepiece. Pro viding respiratory protection for individuals wearing corrective glasses is a serious problem. A proper seal cannot be established if the temple bars of eye glasses extend through the sealing edge of the full facepiece. As a temporary mea sure, glasses with short tempte bars or without temple bars may be taped to the wearer's head. Wearing of contact lenses in contaminated at mospheres with a respirator shall not be allowed. Systems have been developed for mounting corrective lenses inside full facepieces. When a workman must wear corrective lenses as part of the facepiece, the facepiece and lenses shall be fitted by qualified individuals to provide good vision, comfort, and a gas-tight seal. 9.2 Eyewear with Half-Mask Facepiece. If corrective spectacles or goggles are required, they shall be worn so as not to affect the fit of the facepiece. Proper selection of equipment will minimize or avoid this problem. 95 Respirator Use in Low Temperatures. Ma jor problems in the use of full facepieces at low temperatures are poor visibility and freezing of exhalation valves. All full facepieces are de signed so that the incoming fresh air sweeps over the inside of the lens to reduce fogging. Otherwise, it would be impossible to wear a full facepiece in ordinary room temperatures with out severe fogging. Antifog compounds can be used to coat the inside of the lens to prevent fogging at room temperatures and down to tem peratures approaching 32 degrees Fahrenheit. However, below zero degrees Fahrenheit, anti fog compounds will not prevent severe fogging. 26 ,, _ FOR RESPIRATORY PROTECTION Z88.2 Full facepieces are available with nose cups that direct moist exhaled air through the ex halation valve. A properly fitted nose cup should provide satisfactory or adequate visibility at temperatures down to --30 degrees Fahrenheit. At very low temperatures, the exhalation valve may collect moisture and freeze open, al lowing the wearer to breathe contaminated air, or freeze closed, preventing normal exhalation. Tho Bureau of Mines has published two pam phlets on this subject: Performance .of OpenCircuit Self-Contained Breathing Apparatus at --259 F, R.I. 7077 (1966), and Low-Tempera ture Performance of Compressed-Oxygen Closed-Circuit Breathing Apparatus, R.I. 7192 (1968). Dry respirable air shall be used with self-contained breathing apparatus or air-line respirators at low temperatures. The dewpoint of the breathing gas shall be appropriate to the ambient temperature. High-pressure connections on self-contained breathing apparatus may leak because of metal contraction at low temperatures. The connec tions should not be overtightened since they may break when the temperature returns to normal. 9.4 Respirator Use in High Temperatures. A man working in areas of high ambient or radiant temperature is under stress. Any additional stress resulting from use of respirators should, therefore, be minimized. This can be done by se lecting and using respirators having minimum weight and breathing resistance. Supplied-air respirators and hoods and suits having an ade quate supply of cool breathing air are recom mended. Further information on use of respira tors in high temperatures may be found in Breathing Apparatus for the Fire Service, pub lished by the National Fire Protection Associa tion in 1966. 9.5 Communications. Although conventional respirators distort the human voice to some extent, the respirator exhalation vslve usually provides a pathway for some speech transmis sion over short distances in relatively quiet areas. Talking can induce facepiece or compo nent leakage and therefore should be limited while wearing a respirator, especially those with half-mask facepieces. Mechanical speech transmission devices called speaking diaphragms are available as an inte gral part of some respirators. These consist of a resonant cavity and diaphragm which amplify sound in the frequency range most important to speech intelligibility. The diaphragm acts as a barrier to the ambient atmosphere. It should be carefully handled and protected by a cover to prevent puncture. Various methods of electronically transmit ting speech from the respirator are available. These utilize a microphone connected to a tele phone or radio transmitter. Usually the micro phone is mounted in the facepiece, while the amplifier, power pack, and loudspeaker or trans mitter are attached to the exterior of the mask, carried on the body, or are remotely located. Respirators with electric or electronic speech transmission devices having an integral or bodyattached battery power supply should be used with caution in explosive atmospheres. Sealed power sources should be checked for integrity of seals. Connecting cables from microphones inside the facepiece shall have gas-tight seals where they emerge from the facepiece. When the loudspeaker diaphragm is part of the barrier between the respirator wearer and the ambient atmosphere, it shall be frequently inspected for leakage and should be adequately protected from puncture or rupture. The assembly of an electronic or electrical speech transmission de vice into a respirator shall be avoided if it re sults in a center of gravity and moment of iner tia such that the mask may be dislodged from the face during wearer activity in a toxic en vironment. Removal of speech transmission de vices may allow contaminant leakage into the facepiece. 9.6 Noneonventional Respirators. Special res pirator designs, such as `Sieck respirators" for persons having a tracheotomy, may present problems not commonly encountered with con ventional respirators. Therefore, the manufac turer should be consulted for special guidance or precautions. 10. Evaluation of Respirator Program Effectiveness 10.1 General. Feedback on how a respirator program is functioning is necessary if manage ment is to maintain effective respiratory' pro tection. Program improvements and elimination of deficiencies cannot be effected unless the pro gram is monitored and evaluated on a continu ing basis. The following techniques are used in evaluating the effectiveness of respirator pro grams. 27 33c, , 788.2 AMERICAN NATIONAL STANDARD PRACTICES 10.2 Wearer Acceptance. The effectiveness of a respirator program can he largely determined by the degree of worker acceptance. Numerous factors affect the worker's acceptance of respira tors. These include comfort, ability to breathe without objectionable cflort, adequate visibility under all conditions, provisions for wearing pre scription glasses if necessary, ability to commu nicate, ability to perform all tasks without un due interference, and confidence in the facepiece fit. Failure to consider these factors is likely to reduce cooperation of the wearers in promoting n satisfactory program. How well these problems have been overcome can be determined by ob serving wearers during normal activities and by soliciting their comments. 10.3 Examination of Respirators in Use. Res piratory protection is no better than the respira tor in use. even though it is worn conscien tiously. Frequent random inspections shall be conducted by a qualified individual to assure that respirators arc properly selected, used, cleaned, and maintained. 10.1 Evaluation of Protection Afforded. When respirators arc worn in toxic atmospheres, the individual should be provided appropriate peri odic laboratory tests. These may include urine, blood, or fecal analyses and other techniques to determine.* the intake and excretion of toxic sub stances. The findings of these tests, when corre lated with other exposure data (especially air sampling data, as descril>ed in 6.3.4) for wearers of such equipment, can serve as an indication of thu effectiveness of the program. Positive evi dence of exposure shall lie followed up to deter mine any relationship to inadequate respiratory protection and need for additional engineering controls. Nasal or fnccpiccc interior smears, or both, usually will detect any significant penetration of radioactive contaminants into the facepiece. 11. References (o Other Codes, Standards and Manuals 11.1 American National Standards Institute. When any of the following American National Standards is superseded by a revision approved by the Standards Institute, the revision shall apply. 11.1.1 American National Standard Identifi cation of Gas Mask Canisters, K13.1-1967 11.1.2 American National Standard Method of Marking Portable Compressed Gas Contain ers To Identify the Material Contained, Z48.11954 11.121 American National Standard Practice for Occupational and Educational Eye and Face Protection, Z87.1-1968 11.1.4 American National Standard Safety Guide for Respiratory Protection against Radon Daughters, ZS8.1-1969 11.2 Compressed Gas Association 11.2.1 Commodity Specification for Air, Spe cification G-7.1,1966 - 1L2 Compressed Air for Human Respira tion, Pamphlet G-7,1968 11.3 Interstate Commerce Commission; U.S. Department of Transportation 11.3.1 Code of Federal Regulations, Title 49, Parts 71-90, Rules and Regulations for the Transportation of Explosives and Other Dan gerous Articles 11.4 U.S. Department of the Interior, Bureau of Mines. See A2.1 in the Appendix to this Standard. 11.4.1 Schedule 13E, Self-Contained Breath ing Apparatus, Code of Federal Regulations, Part II, Subchapter B, Chapter 1 of Title 30. 11.4.2 Schedule 14 F, Gas Masks, Code of Fed eral Regulations, Part 13, Subchapter B, Chap ter 1 of Title 30. 11.4.3 Schedule 19B and Amendments to Schedule 19B, Supplied-Air Respirators, Code of Federal Regulations, Part 12, Subchapter B, Chapter 1 of Title 30. 11.4.4 Schedule 21B, Filter-Type Dust, Fume, and Mist Respirators, Code of Federal Regula tions, Part 14, Subchapter B, Chapter 1 of Title 30. 11.4.5 Schedule 23B, Nonemergency Cos Res pirators (Chemical-Cartridge Respirators In cluding Paint-Spray Respirators), Code of Fed eral Regulations, Part 14a, Subchapter B, Chap ter 1 of Title 30. 11.1.6 Performance of Open-Circuit Self-Con tained Breathing Apparatus at --25 F. R.I. 7077, 1966. 11.1.7 Low-Temperature Performance of Com pressed-Oxygen Closed-Circuit Breathing Ap paratus. R.I. 7192, 1968. 28 3*1 ' FOR RESPIRATORY PROTECTION 11.1.8 Information Circular 8281 (October 1, 1965 and annual supplements). Respiratory Protective Devices approved by the U.S. Bu reau of Mines. 11.5 U.S. Department of Agriculture 11-5.1 Respiratory Devices lor Protection Against Certain Pesticides, ARS-33-76-2. Feb ruary 1966 (addendum March 1,1966). 11.6 General Services Administration 11.6.1 Federal Specification BB-A-1034a (June 21, 1968). Air, Compressed for Breath ing Purposes. 11.6.2 Interim Federal Specification GG-B00675b (April 27, 1965). Breathing Apparatus, Self-Contained. ZRfl.2 11.7 American Industrial Hygiene Associa tion and American Conference of Govern mental Industrial Hygienists. 11.7.1 Respiratory Protective Devices Man ual, 1963. 11.8 National Fire Protection Association 11.8.1 Breathing Apparatus for the Fire Serv ice, 1966. 11.9 American Conference of Governmental Industrial Hygienists 11.9.1 Threshold Limit Value of Air-Bomc Contaminants for 1968, Recommended and In dexed Values. (1968 or latest revision.) 11.9.2 Documentation of Threshold Limit Values, 1962. (1962 or latest revision.) 29 J Appendix Respirator Approval and Acceptance Listings (Thin Appendix in not a part of American National Standard Practices for Respiratory Protection, Z88.2-1969, but is included for information purposes only.) Al. Approved or Listed Respirators The Department of the Interior, Bureau of Mines, and the Department of Agriculture pub* lish frequently revised lists of respirators. Sam* pies of these have been tested and found to pro* vide satisfactory respiratory protection against specific hazards or contaminants. Al.l Respirators Approved by the Depart* ment of the Interior, Bureau of Mines. A list of respirators approved by the Department of the Interior, Bureau of Mines, may be obtained from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. A 1.2 Respirators on Lists Published by the Department of Agriculture. A list of respira tors for respiratory protection against certain pesticides may be obtained from the Depart ment of Agriculture, Pesticide Chemicals Re* search Branch, Beltsville, Maryland 20705. A2. Requirements for and Tests of Respirators Requirements and testing procedures for res pirators have been established and published by the Department of the Interior, Bureau of Mines, and the Department of Agriculture. A2.1 Department of the Interior, Bureau of Mines. Requirements and Tests. Requirements for approval of most types of respirators used have been established. These requirements are published os the Department of the Interior, Bureau of Mines, schedules. A current list of these schedules appears in Section 11, Refer ences. These schedules are frequently revised and each subsequent revision is assigned a suc ceeding terminal letter (for example, schedule 19B is a revision of schedule 19A). Copies of the most recent schedules may be obtained from the Publications Distribution Section, Department of the Interior, Bureau of Mines, 1800 Forbes Avenue, Pittsburgh, Penn sylvania 15213. The Department of the Interior, Bureau of Mines, approval on a respirator continues in ef fect even though the schedule under which the respirator was approved has been revised one or more times. If the user wishes to check the minimum performance he may expect from an approved respirator, he should consult the schedule which was in effect when the approval was granted. Certain respirators are upgraded by the manufacturer to meet the requirements of more recent schedules. In general, each sched ule revision makes the requirements more se vere. A complete list of schedules and their effective dates, and a list of schedules under which each respirator has been approved, will be found in the Bureau's list of approved res pirators. Responsibility for testing and approval of pesticide respirators has been transferred to the Department of the Interior, Bureau of Mines. A2 Department of Agriculture Require ments and Tests. The Department of Agricul ture previously established requirements and tests for respirators intended to provide respira tory protection during the application and han dling of pesticides. The requirements and tests are described in a publication of tests and re quirements for respirators designed to provide respiratory protection against pesticides. The publication may be obtained from the Depart ment of Agriculture, Pesticide Chemicals Re search Branch, Beltsville, Maryland 20705. In the Department of Agriculture's tests, pes ticides were dispersed as water sprays, oil sprays, or dry dusts to simulate formulations used in field applications. Chemical cartridges were tested for one hour and gas mask canisters for four hours. Insect bioassay methods were used to determine the efficiency of canisters and cartridges. The Department of Agriculture did not eval uate facepiece fit of chemical-cartridge respira tors or gas masks. It did not test respirators for protection against rodenticides, herbicides, and fungicides. 30 331 ( ^APPENDIX A3. Selection of Other Than Approved or Listed Respirators For special purposes the user may need to select a respirator which has not been submitted to the Department of the Interior, Bureau of Mines, or to the Department of Agriculture for testing, or cannot be tested by these agencies because it is outside their approval or testing authority. Among these are special-purpose res pirators for which user demand does not warrant submitting the devices for testing or approval. Z88.2 The user should compare unapproved respira tors with similar approved or listed doviccs to evaluate the facepiece and other parts to assure himself that the manufacturer, or other reliable organization, has tested the filters, cartridges, or canisters, that they are adequate for the re quired service, and that quality control during manufacture can be expected. He should make or have made suitable tests of the respirators' effectiveness which, as far as feasible, simulate tests made by the official testing agencies.