1. Keep away from heat, sparks, open
flame.
LIV. Chemical Safety Slide Rule
2. Avoid spilling, contacting skin, eyes,
elothing.
3. Use adequate ventilation or personal
T h e Natimt:rl Snfrt y ('unn~.ilIms d e w oped a clletni(.id safety slide rille which is both iuenpelwive a n d a,, ercelleut b n s i ~ s m r e e $,f htlnard d a t a a i d refelenres. Because t h e E d i t w id tlril; ~:olutnnbelieves st,rwgly t,lral llru Cl,ernied Safety Slide I:& is the m m t weful low-p~.icpd g l ~ i d e nvnilsble, we are u s i ~ i gillr clanofnrtnviug Cl~emisbs' Association, o r Arr~erirall I t ~ r l u s ( ~ ~Hyial giene Asaxiatiwl. H u a d ijdu~.mntiwb iwlodes flash point, scvwity a d t y p e of hxaards, pl~eanubiwwto tnke, oral tosieity, action oo skin, fiwl aid, nud t h e health, Hammahility, and instability llnzusd s i g d ~ ~ n r h o established rs b y t h e N : ~ t i m a lFire Proteeticn~> Associntiorr(NFPA). An i t ~ l m d n r l o r ypnmgraplr 1111 t h e Slide Rule explilin~t h a t t h e severity of haoards depends ,,>Iiho ~.aLcof generatim of ail.Ijorlie rcnltnrninn~,ts,t h e i~kIensit,yof exp a s w e ctr lirnc of rontncl, a d t h e mmtn,l m e a s w e o s c d T h e same paragral,l~ otnphuiizes 111;tt e n d >ltwz:t~.d.(.'. 2UUU!J cut Ave., N.\V.. Wiibli~uiit~~i. Sce MCA Mmu:d I.-I. IYtil. aSee NI,I'A Nu. 4!lLl!llili. 1
See
Cdu,tir wila Clliorarrr
See N F P A 325 M.1966. Ndltunal Flrc Protection A n n . 00 Balferynarch Bunon. Mars. 021 10.
Figure 1.
Sf..
Detail of Chemical Sqfety Slide Rule.
Volume 46, Number 7, January 7969
/
A29
Safety
.. .
National Safety Counoil, 425 N. Miehignn. Chicago 60611. 12. MCA DATA SHEETS cover safe storace, hnndiine, and use. Manufacturing Chemists' Aasn., Inc., 1825 Connecticut Aue. N W.. Ksshindon. D. C. 20009.
Source and Prices
OCCUI.
2. Must be moderately heated or exposed to relatively high-temperature environment before ignition can occur. 3. Can be ienited at almost all temneratures. 4. Will rapidly or completely vaporize at atmospheric pressure and normal temperatures: or will readily disperse in air and hum easily. 7. NFPA Reactivity (instability) Hazards Susceptibility to release of energy, or oontact with water."Does not include reaction with other materials.! 0. Normally stable, even under fire exposure oonditions. 1. Nonnally stable except at elevated temperatures and pressures; may react with water with some release of energy, but not violently. 2. Normhlly unstable: readily undergoes violent chemical change, but not detonation when contacted with water; mav form ootentiallv mir. erolosive . t u c s with water. 3. Can detonate or ennlode under a strons initiating source, o; after heating under confinement and contacting with water. 4. Readily detonate or explode a t normal temperatures and pressures. 8. Oral Toxicity Rating (For inhalation toxicity see Col. 10) Amount to ~rodueedeath when swallowed by an aver& (150-lb) m a n c 1. Praotieally nontoxic-Takes more than one quart (2 lb). 2. Slightly toxio-1 pint to 1 quart. 3. Moderately tonio-1 oa. to 1 pint. 4. Very toxic-1 teaspoonful to 1 os. 5. Extremelv toxic-7 ddroos to 1 teamoon~
~
~
~
~~~
tions. Pnmary skin irritant-Brief contact can cause inflammation or burns. (d) Can enuse d v e n t irritation-type ~. dermntitis. Referenoes-Detailed safety information is available as follows: 10. AIHA HYGIENIC GUIDE summarizes toxicological data available in order to establish relative health hamrd; recommends control to minimize exposure. Amerioan Industrial Hygiene Assn.. 14125 Prevost, Detroit 48227. 11. NSC DATA SHEETS cover maior hazards, discuss ways to control or ehminnte them, and outline safe urocedures. (c)
' See "Occupational Diseases." Bul. No. 1097, U S . Dept. of Health. Education, and Welfare, 1904. (Available: U.S. Govt. Printing Office)
/
Journal o f Chemical Educofion
Recommendation We believe the Slide Rule should be available to every student and in every lahnratory.
~.
(a) Relatively harmless. (6) Sensitizer-Can cause allergio reac-
A30
Prices before discount are 83 far one Slide Rule, 52 each in quantities from 2 to 9, 61.40 each for qnsntities of 10 t o 99, and 61 each for qnsntitiea of 100 or more. 1)iacnnnt for schools, c o l l e g ~ universities , and other educational institutions (as well as NSC members) is 20%,. 1)iscount for d h e r governmental organizations is 10y0',. The Chemical Safety Slide R d e is puhlished hy t,he National Safety Council, copyrighted 1'167, and is available as Stock No. 120.01 from t,heNat,ional Safety Council, 1)epsrtment JCE, 425 N. hlichigntr Ave., Chiexgo, Illinois 60611.
From lime t o time, it is hoped that these columns can report on accident case histories which may serve the very important fnnction of reminding readers of potential but often neglected hazards.
Nitrogen Dioxide An investigator a t a university inadvertently inhaled a sofficient amount of nitrogen dioxide to require hospitalization. Significant quantities of this gas are used a t many universities; however, frequently those working with nitrogen dioxide are n o t entirely aware of its harmful effects. Typically, nitrogen dioxide is supplied in cvlinders under s. vressure of 14.7 nsia. his reddish-brawn gas a t roam tern&ture is approximately 807, NnOl and 20% NO*. The gas is nnn-flammable; however, i t is a very strong oxidizing agent and has been used as a rocket fuel. From t h e standpoint of physiological effects, this material is considered t o be highly toxic. It is particularly hazardous in that after inhalation serious effects may not be felt for several hours, even though dangerous amaonts may have heen inhaled. The recommended maximum atmospheric concentration to which one may be subjected is 5 ppm far an 8-hr working day. This illcidentally is the a v v r o s i m ~ t eodor threshold. Eavosures
Exposures to concentrations rauging from 60 to 150 ppm will cause coughing, nausea, choking, headache, shortness of breath and restlessness. Pulmonary edemn occurs within 6-24 hr. Inhalntion of lower concentrations may eause edema in up to 72 hr. I t should be noted that the time between inhalation and t h e beginning of edemn is generally free of symptoms.
Safety
...
I t has been estimated that persons I N ally can toloratoa concentration of 25 ppm for R few minutes. Concentrations immediately hasmdow to life range hetween 200 to 700 ppm. Because of the toxicity of nitrogen dioxide, it is imperative that personnel who use the gas be bhoroughly familiar with its properlies. The gas should be used in a hood t o prevent its releaae inio the atmosphere of x laboratory. Persons who are expoxed accidentitlly shordd he seen hy a physician. Lines carrying nitrogen dioxide should be leak test,ed. Tery small leaks can be detected by using wet blue litmus paper. Larger lezks can be seen easily because of t,he colw of the gas.
(Reprinted wilh pwmission fiam " l d o r a lory S ~ f e f y , "a newslellcr of the Campus Safely Aimcialion, V . I I No. 7, Seplembcr, 1987)
FIRES AND EXPLOSIONS n-Methyl Nitrosurea Improperly Stored A quantity of n-methyl nitrosourea was ordered for use by a laboratory. However, before the material arrived, the project for which it was intended had been superseded by one with a higher priorit,y. When the nitrasoorea. mtrrived, it was stuck in a corner of the lab and forgotten about. Several months later, internal pressitre from the slow decomposition of the chemical started breaking the bottles. T h e irritating fumes given off drove the occupants out of the laboratory and initiated 8. general building evacuation. The box containing broken and unbroken bott,les was placed in a. hood by 611 employee wearing s. self-contained breathing unit. Shortly after this, the box caught fire. This fire was quickly extinguished with CO1 extinguishers and water. T h e basic cause of this incident was improper sborage of a material which slowly decomposed a t room temperature. This incident has lead us to reevaluate storage uf such chemicals, but as this is being written, no conclusions have been reached or recommendations made.
(Rep~intedwilh permission from "Research Sentinel," February 1968, Howard S . Brasted, Edilor, Merck Sharp & Dohme, Research Laboralories Division, Rahway, N. J. Acetone Fire A technician was rinsing glassware with acetone a t the sink. Acetone vapors were ignited by a bunsen burner flame in n nearby hood and flashed back to the sink. T h e small fire in t,he sink was quickly extinguished with a C 0 2extinguisher. This fire should serve to remind us to be on the watch for such potentially hazardous sitnations as this. I t also highlights t,he ability of vapors to travel. 111 this case they were drawn toward a. hood in which there was alighted bunsen burner. (Reprinted wilh permission from "Research, Sentinel," Febrtmry 19fi8, Merek Shnrp &
Dohme Research Laboralories Rahway, N . J . 07085
Division,
Tetrahydrofuran is a very popular solvent for certain ~.eactionsinvolving libhiom ablmirn~mhydride reduct,i
