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in the Chemical laboratory Edited by N O R M A N V. STEERE, 1 4 0 Melbourne Ave., S.E. Minneapolis, Minn. 5541 4
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HAZARD SIGNAL POSITIONS
XLVII. Hazard Identification ~ i ~ n a l s Although laburstories irr sevend largo organiaatio~~s are labeling their chemicnls with hasnrd idontifie;ttir,tr s i g d s (to show relative haas~.dof contnct, fil.e, and violent reaction), there have !lot been adeqoabe definitions which ccuuld be used by other organisations t o select signals on a cumparable basis. Perhaps a fundameutal problem is agreement uu the primary purpose of chemiml hasard identificatiutr signals-who most need8 protection. We believe the users of chemicals, in the broad sense, are most i t ) lceed of p1.oteetion and have the most to gain from standard use of haaard identification signals. I n this article we want t o offer some arguments for relnt,ing hassrd signals t o user needs primarily, recognizing also t h a t the signsls will be helpful to fire and emergency personnel. The main purpose uf this article, however, is to set forth some tentative gnidelines which ceuuld be used for selecting h a ~ a r didentification sigrmls. I t is hoped that these telrtntivo guidelines will not be adopted uncriticnlly, but will serve as s point of departure for the development of appropt.iale standards and tests which are reproducible within acceptable limits. Benefits of H a z a r d S i g n a l s The hasnrd identification system which has been adopted by tho National Fire Pmbecliun Association, t o guide fire fighters, was npparcntly fiwl developed by James J. Iluggan for prutection of plant pel.sonnel of Union Carbide Co. Since mare people are a t risk in making s n d using chemicals than in fighting fires involving chemicnls, it seems important to see that definitions of haaard siguals relate first t o the needs of the makers and users, and second to the fire fighters. Fortunately, t h e definitions used in NFPA 704M nre srtitablo to bvth groups, with a. few exceptions which will be noted. The interest uf make1.s and users of chemicsl.; do coincide with the interests of fire fighters since laboratwy and plaub emphyees are often in fim brigades or emergency squads which respond first t o chemical leaks, spills, aud fires. Uniform chemical hazard identifieatiou signals will benefit both gt.oops since labornloty and plant employees are not generally any mom awa1.e or knowledgeable about chemical haaards that, are firo fighters or other emergeucy personnel called on t,o control spills and fires. The Rrnctionel use of hazard identification signnls is t o provide a qtiiek and simple means of tolling from a distance what are the relative hazards of persoual
injury, fire, or iustability. The symbol can be used on tank trncks, storage tanks, containerized cargoes, warehouse sections, storage rooms, shelf sections, drums, bags, pails, and bottles. Personnel can easily learn blrat higher nnmbers meau higher hazard and bhst spoeial handling is required for use of m y material with a hasnrd grade. I l m d l i ~ l g vf chemicals with a. health hazard grade uf 3 or 4 will ~ ~ s u n l lrequil.c y respiratory protectioneither. special vc~dilxtionor self-eol~bained air masks. Chemicals with fire hazard grades of 3 or 4 me very likely to bc ignitiblc undor normal temperutwo eoudition-which calls for control of iguition sources and ventilation, rootiuely or ill ease of spills. Ilssard identifientiuu signals are not inteuded tu take the place of adequate labels with precautionmy st.atements that pmvide full itlfornrstivt~. However, i t seems essential t o provide ;L uniform system to sigtral the impurtauce of reading the labels or approaching the lank, vehicle, or container with npprqmiate methods. Evcn if chemical n s n ~ e swere used on all chemical con1sinel.s it would nut provide a geueral guidc to the relative hxsal.ds of contents, as hasard identification signnls will. Hazard ide~~tificntim signnls on chomical cuntitine~.~ can make it colweuie~ltt o segregate bulk storage in warehouses nlld stuck mom.; for better protection awl control of emergencies. hI.ztel.ials with high fi1.e hazard cat) be locctled whcrtl spl.inkler protediotl is best nud spccinl five extinguishers :o.c most lradily :~v:tilal,le, :mid materinlr with high hcalth li;m;mI em, be located where special veutilat.ivu a ~ d protective cql!ipmenl s1.e ,zv;~il;rble. Determination of H a z a r d Signals I)ete~.rninslionof ohernieal haxard signals apprvpl.iale lo the wwking defiuitiu~w which may finally be stiind;,rdized, depends on sperifio knowledge uf health, fil.e, and inslnbility h:aaal.ds, 01.on the hest, judgmont possil,le. T h c primary respmsibilily fur detesm\ning or seleet,ing appnqxi;~te hasaid signals, we believe, should be exercised in the laboratory. While toxicolugists, physicians, and industrial hygiene personnel are logical p~.ofessionals t u assign health hazard signals, the size of the task, and the impurtance of timeliness, make i t necessary for respvnsible personnel l o assign 11aaul.d grades on a preliminary basis. I n t h e next major section are listed tho definitivns of NFPA hsaard signals, with
Hazard (Red) Health Hazard (Blue)
Stability Hazard (Yellow)
v Informntion (White)
examples of ehemienls which have been assigned various hazard signs. I n the final section are the health hnsnrd definitions used by one large organization and theanimal test bases for assigning hn~a1.d grades.
NFPA H a z a r d Identification S i g n a l s T h e lraossd signals listed were established by the Nutiand Fire Protectiim Association ns set forth in their puhlication, "Identification System fur Fire Hazards of Msterials," 4 - 1 1 l!lFG, which identifiw hasards as follows: ldenfification o f Health Horord 4-hlaterials which on very short exposure could cause deaah ur major residual injury even though prompt medical t,roatment were given. Acrylonitrile Parathhm Bromine :3-hIaterinls wl~icll on sho1.t esposwc could m u s e swious femgor:try r r residu:~l it,jut.y evcn though ~ m m p t modicsl 11.ealrncnt were given. (Inrluclt:s nt;iln.i;~ls C I I I ~ I ~ I I C ~ VloC liviug tissue or toxic by skin nhsot~ptirn~.) Acctyl Chlcride Sodium I,ydl.mide Aniline Sulfuric; id 2-hlnterids which on inleme vr itl.ile Aniline
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Ilydrogeu vhlorido Ilydwaen s~dfide .\lethmiol \lclhyl hillfoxide Nitric acid Phenol Fyt.idine Sodium hydl.tene Xvlene llela1,ivc hnmrd 2-2 or 4 hours inhalalion kills 2, 3, or 4 of 6 rats. Relative haaard 1-8 harm inlralatiorr kills 0, 1, 2, or :3 of 6 mts. The test desc~.ibedis st,rict,ly a lest of haaard, the likelihood that a mhtel.ial free t o evaporate a! room t,ernperature, will prodme z vapor eoncentrat,ion which will
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NFPA TTealth -1IEALTII IIAZARI) GRADES-Ilasard Eve Skin Skin Slg~rsl Contar1 Inhalatio~l Penetration Irritation
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be injurious to breathe far a short period. The relative haaard of breathing dusts and some volatile materials has been estimated from other tests, believed to be consistent with the above. When the l,nsard is based mortaliLy 6 rats weighing 90-120 inhaling know,, vapor collcell~ratiollsfor 4 hours (Cmllnued on page ,4462)
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far 14 dnys thereafter, thc experimental
Skin Penelmlion. L l j , ~ir tho dosage killing half of n gmilp of male nlbino I.& bits weighing atmilt :ikg, within 14 dnys followiug ,zdministmtim by 24 1tonl.i' contact with about 401j, uf thc body a i u face. llolntive hnnnrd 5-12116a lcss lhntl 0.02 ml/kg. llelalivc hnsnrd 4-LIj,, 0.W 11, 0.1!1 ml/kg. 1lel;tlivc Ira~nrd 3-1,Il~ 11.2 to 1.W ml/kg. llelntive hamrd 2-LIk 2 I 0 XI rnl/kg. Ilelative hnaard l - L h more t h a n 20
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