Document B8kdKD6nn8xVZ0XM6NjyNandw

t ; * > I A i 1980 rcW 23 AH 3 : 3 1i / i i t i yu: fj i'/<r '"'t `> "A'<* 8. / *i?e' '~?r~' M<i 7 '/ 'f&Z-t.t/ ^^-4 '/"^w ' ` ' /j'W*O W rvk'/^/ ' / /, ,, /: -- , PLAINTIFF'S EXHIBIT FD-1081 RUSS QUARLES i J PQI8004 1211 SCF-ALLF-08120 Establishing an Effective Respiratory Protection Program REDUCTION AND CONTROL OF RESPIRATORY HAZARDS A primary objective of respiratory protection is to reduce or eliminate hazards at their source by means of sound engineering control methods. X he control of air contaminants in the industrial environment is both a moral and a legal obligation-- particularly in view of our present emphasis on health, safety, and Establishing an Effective Respiratory Protection Program 1. Introduction--(April 19711 2. Program Administration -- (May 1971) 3. Human Respiratory System --(June 1971) 4. Respiratory Hazards--(July 1971) ecology. The Occupational Safety and Health Act of 1970 is specific relative to the control of the in plant environment. The following is quoted from the May 29, 1971 issue of the Federal Register, which details the present standards appli cable to the act: Subpart G--Occupational Health assd Environmental Control 1910.93 Air contaminants. (Gases, vapors, fumes, dust, and mists.) a) Exposures by inhalation, in gestion, skin absorption, or con tact to any material or substance 1) at a concentration above those specified in the Threshold Limit Values of Airborne Contami nants for 1970 of the American Conference of Governmental In dustrial Hygienists, listed in Table G-l, except for the American National Standards listed in Table G-2 of this section and except for values of mineral dust$ listed in Table G-3 of this section, and 2) concentrations above those specified in Table G-l, G-2, and G-3 of this section, shall be avoided, or protective equipment shall be provided and used. b) To achieve compliance with paragraph (a) of this section, feasible administrative or engi neering controls must first be de termined and implemented in all cases. In cases where protective equipment, or protective equip ment in addition to other mea sures. is used as the method -of protecting the employee, such protection must be approved for each specific application by a competent industrial hygienist or other technically qualified source. 5. Hozord Assessment--(Aug ust 1971) 6` Hozord Control ---(Septem ber 1971) 7. Personal Protection--(Octo ber 1971) . 8. Training, Inspection, and Maintenance -- (November 1971) 9. Medical Surveillance--(De cember 1971) Reprints of each article in this series will be available from the Council within 60 days after publication. Coauthored by C. R. E. Merkle, Jrn product Line manager, Mine Safety Appliances, And by I. B. McDonough, P.G., supervisor. Filter Division, Mine Safety Appliances, Pittsburgh. 8004 1212 z The Clean Air Act of 1967, and its amendments, likewise details the standards for ambient air quality governing the "macro-environment" or outer plant. In this regard, it is particularly important to be aware of the state and local air pollution control laws that prevail. The control of the in-plant en vironment is specifically directed at providing respirable air and a clean "micro-environment" for the work er (see accompanying illustration). (Control on the macro-environment entails not only health but other considerations--both ecological and aesthetic.) Control of both the macro- and micro-environments are equally im portant, however. But the controls exercised for each are not totally compatible with each other. For ex ample, one can provide effective individual environmental control, and thereby a clean micro-environ ment for the worker, at the expense of contaminating the outside air to excessive levels. Merely sweeping the ashes under the rug, so to speak, or sweeping contaminants up the chimney is not the total answer. However, air pollution control is a total subject in itself. The scope of this article is lim ited to the control of respiratory hazards in the "in-plant environ ment." Even so, the subject is ex tremely broad, and only basic prin ciples and guidelines are presented here. The primary objective is to re duce or eliminate respiratory haz ards at their source by means of sound engineering control methods. The process development, equipment selection, and plant design stages so are the "opportunity stages" where the possibility of airborne effluents should first be considered, and means of reduction and control should be instituted. The industrial hygienist and safety engineer should participate as members of the pro cess development and plant design team, along with other specialists in ventilation and process control. Ideally, process consideration should include the selection of raw mate rials of the lowest toxicity and of equipment with built-in contamina tion controls whenever possible. Moreover, during the plant design and layout stage, consideration should be given to isolation and encapsulation of the critical process units most likely to contribute to air contamination. Likewise, pre vailing topography and meteorolog ical conditions might suggest safer locations for the critical process units to reduce exposure to other plant areas and personnel in emer gency situations. Because the "opportunity stages" generally knock but once, we are confronted mostly with the control of existing operating processes and equipment. In any case, assessment of the hazard relative to type, con centration under various conditions, and other pertinent characteristics-- such as particle size, flammability, etc., is requisite to the selection of the proper control methods. In addition to substitution with less toxic materials, isolation, and encapsulation, the basic control methods include local exhaust ven tilation and collection of contami nants at the source. Dilution ven tilation is not as effective due to the large volumes of air generally required and the high cost of its conditioning. Also, dilution ventila tion may disperse the contaminants to other working areas. Suggested methods of control according to the type of hazard are listed in Table 1. Common Control Devices Oxygen deficiency control Oxygen deficiency can occur in confined spaces due to displacement of air by other gases and vapors and due to consumption of oxygen through metabolic or oxidation processes. Immediate ventilation with fresh air is the most expeditious solution. Fan blowers and venturi-type air movers can be used effectively for this purpose. TABLE 1 Hazard Control Methods Hazard Oxygen Deficiency Gaseous Contaminants Particulate Matter Type* of Control Ventilation Oxygen Supply Ventilotion Scrubbers Sorbent Bed Combustion Ventilation Inertial Separators Centrifugal Separators Electrostatic Separators . Scrubbers Fibrous Filters 8004 1213 Heftt.r id eto ir- -Tempcroturi Controller .eeuperttlve Heet Exchange Outlet Figure 2 it a schematic of o cololytic burner, typical of those used in the control of goteous respiratory contaminants. age price of 65 cents a pound for a reasonably good, effective char coal. A charcoal cartridge ranges in price from $125 to $450 with an average cost of $250 for a good performance cell. Shortcomings of activated charcoal are: 1) The sorbent bed must be pro tected from particulate matter--an efficiency greater than 50 per cent NBS particulate filter is necessary; 2) The activated charcoal must be replaced or regenerated; 3) In most applications the gas temperature through the cell should be less than 110 F. Combustion--Most vapors and gases that can be removed by ho mogeneous and heterogeneous com bustion are hydrocarbons or organic compounds. Homogeneous or ther mal combustion is a very high tem perature operation (greater than 1,000 F), and it is mostly employed in air pollution control systems. Heterogeneous combustion or cat alytic combusion is usually used when no other system is available. For example, hydrogen, carbon monoxide, and some hydrocarbons are not effectively removed by means of a granular sorbent. A typi cal flow diagram for a catalytic sys tem is illustrated in Figure 2. Figure 3 depicts typical hydrocarbon per formance at various temperatures. The system cost depends upon the application. It is not unusual to figure a minimum cost of $10 per cfm. Particulate contaminant control Basically, there are three mech anisms available for removing par ticulate matter from a gas system: disposable fibrous filters; electrosta tic precipitators; mechanical separ ators. Disposable fibrous filters are probably the most widely acceptable method used today for removing particulate matter from the air that is used in a working environment. Table 2 lists the most common type of filters. The viscous impingementtype filter (common furnace) traps particulates much the same way molasses traps flies. A tackey ma terial is sprayed on the glass or metal filter medium, and it captures the particles by inertial impaction with subsequent adhesion. These fil ters are normally used as prefilters, because they have poor dust holding capacities, and their efficiency on particles less than two microns in sire is very low (less than 10 per cent). The dry fibrous-type filter uses an extended surface for the filter area, and, in general, it operates on a straining principle. The filter medium is usually in a pleated form, which permits the effective filter sur face to be much higher than the projected face area of the filter cartridge. The extended area offers lower filtering velocity and generally a high dust holding capacity. It is not unusual to hold greater than 3,200 gms of NBS dust on a dry fibrous filter that has a particle efficiency of greater than 97 per cent on particles greater than one micron in size. 1S ils. ' " al <s '' Figure 3 shows on exompie of typical cotolytic performance curves. 8004 1214 32 *8 TABLE 2 Classes of Particulate Filters dosses of Filters Initial &P @ Rated Capacity (In Inches) Typical Size (In Inches) Typical Rated Flow (In CFM) NBS Atmospheric AFI Stain Artificial Approximate Efficiency Weight Element (In Per Cent) (In Per Cent) Cost Viscose (oiled) Fibrous, Impingement (Common Furnoce Filter) Viscose (oiled) Metallic, Impingement `Dry, Fibrous Low-Medium Efficiency **Dry, Fibrous Medium Efficiency .08-. 12 WG 24 x 24 x 2 .08-.12 WG 24 x 24 x 2 24 x 24 x 29 .20-.4 WG 24 x 24 x 11 % 24 x 24 x 29 .20-.50WG 24 x 24 x 11'/, 2500 2500 2000 2000 5-12 5-12 50-55 80-85 65-75 65-75 100* 100* .25-2.00 $8-512 $25-$35 $25-$40 "Dry, Fibrous High Efficiency ' 24 x 24 x 29 .35-.60 WG 24 x 24 x 11'/, 2000 90-95 100* $25-$45 Dry, Fibrous Hospital Type .30-.50 WG 24 x 24 x 11 V, 1000 100* oO $50-$90 Dry, Fibrous, High Inter ception High Efficiency Particulate Air Filter .70-1.2 WG 24 x 24 x 11 V, 1000 100* oo $60-5100 'Essentially 100 per cent---Evaluation method not sufficiently critical to detect penetration. 'NOTE: To identify these classes better, the efficiencies reported are comparable to those for commercial electrostatic precipitators on the atmospheric air NBS dust spot lest. It should be noted that manufac turers report filter efficiencies vari ous ways. Hence, a full understand ing of type of filter and the filter efficiency is necessary to obtain a satisfactory system. Shortcomings of a fibrous partic ulate filter are: 1) It adds resistance to the exist ing ventilation system; 2) It must be replaced about once a year; 3) It requires relajjrely large space. ..*? Electrostatic preciptators use a high intensity electrical field to charge particles, which are collected on an opposite charged surface. The uoits vary in size from less than 100 cfm to thousands of cfm. A good average cost of a 500 cfm unit would be approximately $500. The collecting efficiency would be equal to the previously mentioned dry fibrous medium-type filters. The units offer excellent efficiency at low pressure drops. However, in gen 33 eral, the initial cost is high, frequent maintenance is required, and it is not uncommon to generate ozone and oxides of nitrogen. tant that they be selected with ut most care to ensure that proper protection is afforded.--End. Mechanical separators range from simple settling chambers, which em ploy gravitational forces, to sophis ticated devices such as centrifugal separators. Usually dry-type me . chanical devices have poor removal efficiencies on particles less than 10 microns in size. Excellent efficiences are obtained by combining mechani cal separators with a wet method, such as a venturi-type scrubber. Due to the numerous combinations of mechanical separators, their cost varies depending upon the applica tion. Usually, they require less maintenance than other type separ ators. The most likely use for a drytype separator is pre-filtration for high efficiency filters. In situations where it is not feasi ble to create and maintain engineer ing controls, proper respiratory pro tective devices must be provided and used. Because there are many types of such devices, it is impor REFERENCES ASHRAE Guide and Data Book, Systems 1970. American Society of . Heating, Refrigerating and Air-Con ditioning Engineers, Inc., 345 47th St., New York 10017. Industrial Ventilation, 11th edition. American Conference of Governmen tal Industrial Hygienists. Committee on Industrial Ventilation, Box 453, Lansing, MI 48902. Air Pollution Control Manual. Part II--Control Equipment. 1968. Ameri can Industrial Hygiene Association, 210 Haddon Ave., Westmont, NJ 08108. Industrial Health Engineering, Brandt, Allen D. 1947. John Wiley and Sons, Inc., 605 Third Ave., New York 10016. Fundamentals of Industrial Hygiene, edited by Olishifski, J. B. and McEl roy, F. E. 1971. National Safety Council, 425 N. Michigan Ave., Chicaeo 60611. 8004 1215 REPRINTS To Assist In Your Industrial Respiratory Protection Program currently stocked titles ---- Establishing an Effective Res piratory Protection Program gives an overview of areas to be considered in setting up such a protection program. 4 pp. 1) 1.17-63 (April 197!) Respiratory Protection -- Ad ministering A Program de scribes the responsibilities of the individual in charge of a program and the authority necessary to achieve optimum results. 4 op. 111. 17-64 (May 1971) The Respiratory System ex plains the physiology and anatomy of the human respiratory system and its function and how contami nants or the lack of oxygen interfer with this function. 4 pp. 111.17-65 (Jun 1971) Respiratory Hazards to be pro tected against include oxygen-de ficient atmospheres and airborne contaminants. How these hazards affect the respiratory systems are described. 6 pp. 111.17-66 (July 1971) Hazard Assessment describes various processes and related equipment that can create a res piratory exposure hazard. Analyses of these problems is explained. 10 pp. 111.17.67 (Auiutt 1971) Reduction and Control of Res piratory Hazards explains vari ous engineering control methods that can be employed to reduce or eliminate respiratory hazards at their source. 6 pp. 111.17-69 ts*pt<mtr 1971) Personal Protection discusses the types of equipment available to provide adequate protection from the different types of respira tory hazards. 12 pp. 111.17-69 (Octstxr 1971) <AvilbJ early 1972) Training, Inspection, and Maintenance covers the proce dural areas that are required to keep protective equipment oper ating at optimum effectiveness. 111.17 70 (NpvcmbPr 1971) (Availtbli parly 1972) Medical Surveillance explains the role of the physician and auxil iary personnel in monitoring res piratory hazards and employee care. 111.17-71 (Oacamber 1971) (Availablt early 1972) Respiratory Protective Equip ment gives the safety professional a basic explanation of the types of available equipment. 7 pp. 111.17-29 (July 1967) Industrial Ventilation offers an explanation of at-the-source con trol of respiratory hazards. 7 pp. 111.17-10 (Auguat 1967) 8004 1216 M97109 Reprints of .selected JXtiONAI SAFETY NEWS' articles are available shortly after publication; ExcepCas noted, prices are as follows: (10 to 49 copies 2Sc ea.) --(50 to 99 copies 20e*ia.)--(100 to 499 copies 17e ea.)--(00 to 999 copies 8c ea.) Prices for larger quantities will be sent on request. -. Minimum order is 10 copies; it may include more then one title. Payment must accompany orders for less than $5.00. There is a 20 per cent discount to Nation al Safety Council members, and 10 per cent discount to Federal governmental agencies. Make checks payable to the National Safety Council. Reprinted from Notional Safety News National Safety Council, 425 N. Michigan Ave., Chicago, II 60611 Printed In U4A. Ml.17-68