Document 5ZV60ExpL5qwaYgkbe3p8K64

Proposed Revision LKAB Health Practices Pamphlet So. J (Pinal Draft) This pamphlet is one of mors then 150 Safe Practices and Health Practices Pamphlets* It is a compilation of experience in aociuent prevention from many sources. It should net bs assumed, howvar, that It ir.cl des ovary acceptable procedure in the field covered. It mist not be confused with American Standard safety codes) federal lavsj Insurance requirements) stats laws, rules and regulations) and municipal ordinances. Additional, .copies of this paaphlet are available to members of the National Safety Council. Prise1 25 oents per copy, less in qnsr.titles* content* 1* Properties of Lead and Lead Compounds EsgsarMh 2 2. Manifestations of Poisoning a. Entrance of lead into the body 1. Inhalation 2. Ingsstiom 3. Dermatitis 3. Determination of Load in Air a* Impinger b. Slsstroststie precipitator C* Technique in collecting samples d* 'iethod* of lead analysis s* I'axlaua perndsaible concentration 4* Prevention a. Control of environment b. Ventilation s* Respiratory protestive equipment d* Other control mesaurea s. Housekeeping 9 19 20 21 22 26 27 30 31 32 38 40 43 45 47,4,49 50 5* Selection and Training of Employees a* Physical examinations bf Training of employees e* Personal hygiene d. First aid e* fcpporting activities for training 54 58 61 65 66 8 00696 N18371 2 1. This pamphlet is con-fined principally to a discussion of methods of detecting lead poisoning haaords thrvugh checdcal-physioal tests and analyses, safeguarding lead processes through properly design ed ventilation and exhaust equipment, and selecting and training enployees to work safely in lead ex,oarures. -Thila the eff.?cta of lead on systems of the body, manifestations f poisoning, mnd avenues of lead absorption into the body will be listed, 3uch presentation is o.:ly for the _;r.irpose of indicating the importance of adeqi:ats protective measures. Properties of Lead and Lead Compounds 2. Lead and its compounds are among the moat vrLdely used materials in industry, detallia lead is silvery gray, very soft, and has a very low tensile strength. The density of lead is 11.34 (19.94/4 C.), its melting point is 327.4 C. (621.32 F.), and its boiling point is 1620 C. (2943 F.) at atmospheric pressure. Lead is only vory slightly soluble in either cold or hot water, while it is soluble in nitric add and hot concentrated sulphuric add. It withstands the action of most odds to a narked degree at ordinary temperatures. 1`oltsn lead gives off noxious fumes of lead und lead oxide (in measurable quantities at 300 C.) and the quantity of fumes increases with the temperature. The crystalline fora of load is monoclinic. (See paragraph 48 and Figure 1.) 3* hhile lead is the softest of all base metals used in the com mercial arts, it is also the hoavioat. It contracts considerably or cool ingj honos, it is not adapted for casting in the unalloyed state, if shrinkage is important. Lead is very malleable and may e beaten out to 3 any desired hap, but it can ' easily torn sine it lack* tenacity. On exposure to air, load oxidizes v.-r-- q.ic!ly, and its oxide forms a protec tive coating which limit, t' some art nt, further oxidation. X* Galena, or lead sulphide, is the most widely-distributed fora of lead ora. This is found principally in England (in 'ales iind Uarbyahire), in the United States (pri-.cipally in -ioaouri, Idaho, Utah, ' ntana and Ariaona, and also in Illinois, Oklahoma and soae other states), and in Spain and Germany. This ore ia usually fcr>.jid in quart ve!ns or lip--stone beds. Another load ore found in the United Statea is white load ore, or ceruse!t (load car oneta). 5. Lead has many compound* which are used in industry* or.d -.-here the are encountered a lead iiasard may exist. Among the e-nron compounds are the followings Lead acetate (sugar load) Lead arsenate Lead borate Lead carbonate Lead carbonate, basic (white lead) Lead chlorate Lead chloride Lead chromate (chrome yellov) Lead ehrrmate, besic (chrome red) Lead cyanate Lead cyanide Lead dioxide Lead fluoride Lead monoxide (massicot) Lead monoxide, basic (litharge) Lead nitrate Lead oleate Lead, rad (minium) Lead silicate Lead stearate Leed suboxide Lead sulphate lead sulphide .- Vs 00698 5 cription give* no indication i'.iat lead i p-eoer.t. - a result, employees acy, thrugh i jrtu.ee, be expo ?d to a a .ricua loud uaz<_rd, or nay even contract lead poisoning before it i3 discorered that a lead cc.-pcund is in use* Suppliers of lead-contaiair._ aaterinls should issue definite ./arr.ing of the lead c ntent by clearly worded labols; and purchasers should insist on this policy* 'Manifestations of lolaonirA 9* Some kno;ledge rega-ding the action of lead on the body and the symptoms of lead poisoning is valuable to the industrial hygienist and other personnel charged with functional responsibility for results in safety work, notwithstanding the fact that these are primarily the problems of the in dustrial physician. For this reason, the discussion in this pamphlet is confined principally to the prevention of lead poisoning but there is a brief treatment of selected portions of the medical aspects* 10. In^conaidering the effects of lead on the body, it is important to recognize that there ray be individual vari.tions in susceptibility. This and oth-r factors, such as length of exposure, have made it difficult to establish a standard poisonous dose of lead which rculd apply to all persons and conditions. There are, hor/ever, generally acoapted nuudana per- contiruous exposure. rd3S ble limits for 8 hours'/(See P-.irajraph 39.) -herever there is a lead exposure there nay be a potential lead poisoning hazard. The effects of the toxicity :f lead may be v.ry widespread. The f-'llov.ing systems of the body may be concerned* fiZ i 00699 - 6- The blood. The gastro-int^stir.al systesu The nervous .listen Cardio-vnsculcr system (heart-circulation). The urinary r/stem (particularly th kidneys) The reproductive system. \ 11 The first thiru, the layman must realise about lead poisoning is that there is no one subjective symptom or objective clinical ri_p, hich ie po-itively indicative af load poioouing. In some cases so-called "efaronic" lead poisoning may bo one of the most dlff:cult of the occupa tional diseases to diagnose. A physician mu3t make the diagnosis in the light of the history of lead exposure, occupational or otherwise; subjective symptoms; objective clinical rdLgns; and information based on laboratory tests 12 There are, however, general manifestations of the poisonous ef fect of 1-ad absorption* It should be remembered that wherever there is lead exposure there is potential danger fro absorption of the lead. The degree of danger depends upon the extant end duration of the exposure and the control measures in effect, "''ac of the usual manifentati ors of lead absorption are listod below. Tier these ra.-nifestations 're noted, the individual should at cnee be referred to a physician for thorough examin ation and any necessary treatment a Disturbances of the digestive syste, in Ihe fora if laek of appetite, constipation, vague abdominal diecomfort, and in more severe cases severe cramping ab dominal peine (colio). b. Pain and stiffness in joints, bones, and musel-s (particularly the muscles most used.) c. General weakness, loss of weight, and pallor 00710 - 7- d. Loos of strength In the f'r.jars, bends, or forearm, and inability to use them in the performance of custoorry taahs. (3ae ~'z e. to the '-lood, r-cssibly a<r-3i!j nr rda. 13 Tn add.ltio to the mnnifestations II ;t)d above, ?re .ray be nervousness, -macular twitching and trerrors, particrl'rly :f the firmera. The ir.ci. 'nc rf fever i3 rare, but there nay cccasio.;.H y be a 3ll ;ht jaundice and sometimes ir.creaced blood pressure. iV-raetines 1 -lead encephalopathy (disorder of thi rain) irrltablllt', oxcttrer.t, delirium, cccvulsions, end ocular disturbances such as arblyopia or blindness occur. L/* Acti e lead poisoning cases may fall into one of the definite type# familiar to industrial physicians, but the co-existence of more then is one type/also recognized. fHis merely emphasise# that the above recital of manifestations of lead poisoning are for use in prsvertion of the occurence of disabling diseases and that there should be thorough medical supervision of all employees exposed to lead hazard*. It is obvious that where case* of lead absorption are detected r.ri., the initial stages, the individual can be removed from the hroard and the onset of load poiso-.irg prevented, over where Individuals are t ought to be oxr.ojed to only a minor lead ab sorption hazard and are raferred to a physician, urine and blood tests may indicate too much lead absorption, -ere, again, when the victi.o car. be removed from the exposure ur.d adequate treatment given, development of lead Intoxication rrill be prevented. (dee paragraphs 17 and 18 ) 15. The second point which should be clarified is the difference between "ingested lead," "lead absorption," and "lead poisoning." Lead 0G7G1 10 as compared to eithrr Ir option car absorption through the shin, users of lead coop-undo ah*r Id not rso'r.e that tha de*. er 3 *hi . ?' .;re only an Ingestion or hazard of ab-orption t'-r-v -h t'e h 1 -xlats. Absorption throu h t*e s'-'ir. is inportent in the case -t land tetraethyl ard oth=rr organic lead c -g-curds. If snfci nt lead Is noted day after day be- -caune ? in rr-'-'r p-*r3*r.al n-jior.e, 3e-d poigo-4? ;trill certainly occur, 7i'ewise, if load tet.raet7'yl or r-ossibl -.it r load cr.npctids are 'tandied carelessly, abs'rpti r. -.rill tel-o place t'-rou h the a-ir. in suffir"--rt 'p:ar.titles tc ravp roisor.irg. (it has been stated by one authority that absorption through the a-in i3 a factor nhere actors paint the Thole body,) hre the s?in is scratched or irritated, it is :38ible tc abr.srb con siderably -ore load than if the ai-b is unuo-rs*ed. 'rhore tetraethyl is red, this hazard is acute and nust be guarded against. (See paragraph 7,) Xatoltrt .sad 20. then minute particles nf load and its corapounds are inspired with sir, nuch of it is carried into the ncuth or throat .end is either swallowed, e:cp'ctorated, or :iov*n out with the expired'air. The remainder is drawn into the lungs r.d deposited nr the lung tissues. Lend in the I'-ngs is ca pable of ra.id aba rpiio arid distriVti t.into body tissues, since here it is in inti,ante contact with the body flu:.i3. Lead, after dissolving in the lung fluid, is absorb*.-d by the 'lc-od, -..nd vh?r. circulated through the body, "hen thi3 occurs, the lead is dangerous r.nd is capablo, in sufficient quan tities, of producing systemic Jana*e. . 60 00702 12 23* According to Dr*. Fairhall and Sayers, who have conducted exten sive experiments, all lead compounds do not have the same relative degree of toxicity. Some are highly toxic, while others are toxic o-.Jy after long exposure. These two authorities, in United States I'ublic Health Dulletin No. 253* "Relative Toxicity of Lead and some of its Common Compounds," have developed, as the result of their experiments, a table of the relative taxicities of certain lead compounds based on their solubilities, which should be of particular interest to industrial hygienists and toxicologists. 2d Regardless of the relative toxicity of lead conpounds to which an individual is exponed, lead poisoning can and will occur if sufficient concentrations of lead compounds are breathed, or if the worker swallows sufficient quantities over a long enough period. It should not be consider ed that preventative measures can be neglected or even minirdred because the compound in use is allegedly less toxic than others. 25. According to some authorities, the comp rative toxicity of load compounds is based on a number of variables, the most important of which is their solubility in the body fluids. Among the other factors affecting the toxicity are* a Portal of entry. b. Quantity present in the circulation at any given tiae. o. Speed with whioh compound goes into solution. d. Sise and weight of particles. e. Length of tiae in contact with body fluid. f. Quantity inhaled or swallowed. g. Degree of acidity of body fluid. 6 S 00703 - 1 - Mf-rtami permissible concentration 38 The naxinu* concentration of load in ./orkrooa air should not be pend/ted to exceed 0.15 e13.Ilrang per cubic meter (or 1,5 milligrams per ID cubic netsra) for continuous exposure. This standard is generally ac cepted in the United Stateaj among the several regularin,' bodies that adhere to this value are the United States Public Health Service, the Con necticut Departoent of Health, the ''aaaachusetts department of labor, the California Industrial Accident Coianlsalon, the Tllir.oia Department of Labor, the Hew York State department of Labor, and the "Iscor.sin Industrial Cotamission. 39, here teats of workroom air show a greater concentration than 0.15 milligrams per cubic meter, check testa should be rnr.de at once to de termine whether or not the excess of lead found is due to a permanently existing condition in the process or merely to some temporary or unusual condition. here chad': teats show that the maximum peraissii-'le limit is be ing exceeded, steps should be taJan at ^nce to lo-rer the concentration to a 3afe limit. After safeguards have !xrcn applied, routine tests should be made to determine adequacy. In determining whether the maximum permissible limit is beLag exceeded, it is i.-vio'tant that tests be made over an sntire cycle of the operation, and not merely 3orae hi ;h or low point. Control of environment fXSOSf^M, 40. The most obvious method of preventing lead poisoning is to sub stitute for leed and its compounds other materials that are non-toxic. Hoe- 19 i t w , this is rarely practicable, and recourse nust be had to control of environment and training of amployees to prevent the aboorption of lead. 41. tVhen new plants are to be erected for lead processes, they should be designed to minimise lead tsxp^eire, All doors should be of iopervloum material and easily -cleaned. Ledges, window ail!a, structural iron work qr other projections n which oust .-sight lodge should be filled in or angled off. The layout of nachlr.es and equipment should be such that maintenance is made cuy< Arran^-sj ants should be made, wherever possible, to Isolate 11 lead operations 30 that the least number of v.nployuas sill be exposed. Vacuum cleaning systems, discharging the ejdiauat air in a safe laoe, should be built-in while the building is being erected, and the wash, locker and lunch rooms should be separate frum the general work room. In existing plants where it is not possible to build-in permanent vacuum cleaning systems, portable vacuum cleaning apparatus should be used. Such equipment not only makes the cleaning of the plant easier, but in addition males it possible to rerove anat ->)a walls end ledges which 0t.her-.vi3 ni ;ht not be cleaned. Care must be exercised in dumping or cleaning dross from the vacuum cleaners, so that a further lead exposure vrill not be created. The danger of dust on walla and 1 dges, of course, ia that some vibration or draft stay cause it to be swept into the general workroom air. 42. In designing locker rooms, it is preferable that employees ex* posed to lead hasards be provided vith double lockers, one side far their dean doth-a and one side for heir work doth, A liberal supply of man water and soap should be provided, and a sufficient number of shower baths 00709 20 and wash fountains should be installed so that employees gill not neglect cleaning up because of v-oasihle overcrowding* (See Figure 7, a.d Safe Practices Paaphlet No. 27, "Industrial Sanitation (Drinning later, ash and Locker "corns, and Toilet Facilities.)") Tentilatico ' 43. The type of general ventilation and local exhaust equipment ap plied to lead hasards -.Till depend in great measure on the type of building, the particular com;.ounds used, and tie method of manufacture. There are certain fundamentals which should be considered by the engineer designing the system. These are as followst Q> a* ill requirements of the stats department of labor in whieh the plant is located should be carefully followed, and plans should be submitted for approval where this is required or where the service is available* b. Care should be taken when laying out the system that the^air inlet is in such a location that only uncontaainnted air ia drawn into the system. The inlet vol ume should be conmensrate with the exhaust vol'vme. Sometimes it is necessary in cold weather to heat ths incoming air so that the exhaust system will function properly. c. It is preferable r.ot to recirculate to other departments exhaust air frm a department with lead exposure, 'here air is so recirculated or exhausted directly to the ourSlde it is highly advisable to install some system for gk p ^ i 00 71 0 I - 30 - yi Tfl t a4d 65 Thar* ia no recognised first aid for lead poisoning. All case of suspected lead abeor ti n or acute attacks should be immediately referred to a physician. To delay proper treatment may lead to oamplic tions, ^pportlng activities for training 66 The personnel, nedical and safety engineering departments should use erory facility for stimulating and maintaining the health and safety in terest of employees exposed to lead haaarda. For example applicable posters should be used an centrally located bulletin borrds, !>nd should be changed regularly to maintain interest. 67. Other nedluaa for maintaining interest and training employees ('any of them available through the national Safety Council) arei a. Payroll inserts containing health hints. Tfhen paying by check b o m companies clip the insert to the check. b. Sound film strips or moving ..icturec on industrial health and safety. o. Company publications. d. Talks by outside engineers, plant engineer, plant medical officer, or local Safety Council representatives. 68. It may be thought that toe ouch effort directed toward training employees through the use of meetings, literature, role books and other medi ums Till focus attention upon an existing occupational disease haaard. This has not proved true in many large companies There hasarda of the operation were carefully explained and the methods for avoiding them made deer. (See 1^ 1 00720 - 31 Safe Practices Pamphlets "o. 67, n`.lBlntalr.ln1; Interest in Safety," No.77, "Safety 'iratings," and Ho. 93. "Topics for Safety "eet;rjs.") finedal Acknowledgment. In preperin., this pamphlet, liberal use has been r*nAm of the published natarial and personal comenta of Dra. -obart A. Kehoe, Dadd C. Strauss, Elston L. Belknap, S. F. 'eek, Lawrence ", Fairhall, R. R. Sayers, Louis Schwarts, J. C. Aub, Leonard Greenburg, Alice Had 1ton, Carey ?, PeCord, A. .. Xammer, "ilton I;. Vroner.berg and A. Cra-ston. The sug gestions end help given by those authorities were invaluable in the prepara tion of the panphlat. This pamphlet has been revised b John n. '.oche and Ernest J. Downing, Industrial Division, national Safety Council, following the work of a spedal committee of which Harold Chleheiser was chairman. Ihe original drafts were reviewed by members of tha special committeel their valuable assistance and the original work of the committee is gratefully acknowledged. A first'draft of the revision was submitted for aritioism to the Safe Practices Conference Committee, the H alth Practices Conference C curdttee, and authorities on the av.b'ect of lead. The final draft was a.proved y the Executive Coconittae of the National Safety Cornell.