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DATA SHEET 389 (Revised) TRICHLOROETHYLENE The present revision of this data sheet was prepared by the Industrial Department, National Safety Council, 425 N. Michigan Ave., Chicago 60611 and is published by the Council. Introduction 1. Trichloroethylene is a com* mon commercial and industrial sol vent marketed under such trade names as Blacosolv, Chlorylen, Dow-Tri, Nialk, Perm-A-Clor, Phillex, Triad, Triasol, Triclene, and Trimar. Its properties, the hazards associated with its use, and recom mendations for safe handling are discussed in this data sheet. 2. Manufacturers of trichloro ethylene and of the equipment in which it is to be used should be consulted on the technical problems of equipment design, ventilation requirements, and operational pro cedures for maximum safety and economy. Properties 3. Trichloroethylene (CHC1= CC12) is a colorless volatile liquid with an odor similar to that of chloroform. It is miscible in alcohol, ether, and most organic solvents in all proportions, but practically in soluble in water. It is stable in the presence of air, water, and light with any of the common metals at temperatures up to 248 F (120 C). Other physical properties of tri chloroethylene include: Molecular weight ....................... 131.4 Boiling point (760 mm).................. 188 F (86.9C) Freezing point.......... --99 F (--73 C) The informotMMt and recommendation* contained in this publication hov* been cemptied from source* believed to be reliable end to represent the best current opinion on the subject. No warranty, guarantee, or representation is made by the National Safety Coun. cil as to the obsofwte correctness or sufficiency of any representa tion contained in this and other publications, and the Notional Sofety Council assumes no responsibility in connection therewith; nor con it be assumed that aH acceptable safety measures are con tained m Hits (and other publications), or that other or additional measures may not be required under particular or exceptional con* ditions or circumstances. An Alphabetical Index of all Industrial Safety Data Sheets (Stock No. 123.09) is available from the Council on request. Specific gravity of liquid (water ~ 1.0) ..........................1.46 Specific gravity of vapor (air =1.0)................................4.54 Vapor pressure at 68 F (20 C)....................... 60.0 mm Hg Weight per gallon at 59 F (15 C) .......................12.30 pounds Uses 4. Because trichloroethylene dis solves grease, it is widely used in the cleaning of metals, glass, and certain fabrics. In properly designed equipment, it leaves the cleaned piece dry and in good condition for many subsequent operations. It will not dissolve the water soluble in dustrial lubricants, such as soaps or sulfonated oils. 5. Trichloroethylene is also used in organic syntheses, In miscella neous preparations such as liquid 0 NATIONAL SAFETY COUNCIL 1964 soaps, paint and tar removers, rub ber cements, glues, shoe and stove polishes, and in processes such as wool degreasing and depitching. Containers and shipping 6. Shipping of trichloroethylene is not regulated by the Interstate Commerce Commission. It is shipped in tank cars (ICC Specifi cation 103 or 103W), tank trucks, 55-gallon drums, cans, and bottles. 7, The Manufacturing Chemists Association1 recommends that all containers of trichloroethylene bear the following label in addition to, or in combination with, any label, warning, or other statement required by local statutes, regula tions, or ordinances: TRICHLOROETHYLENE WARNING! VAPOR HARMFUL Use only with adequate ventila tion. Avoid prolonged or repeated breathing of vapor. Avoid prolonged or repeated contact with skin. Do not take internally. SL 035392 Storage Trichloroethylene may he stored in galvanized iron, black iron, or steel drums or tanks, or in glass containers tor long periods without change in its chemical or physical properties. Drums should be kept closed to prevent evapora tion and should not be exposed to extreme heat. If trichloroethylene is stored in colorless glass contain ers, they should be kept away from direct light to prevent the formation of acidic decomposition products. Trichloroethylene may be trans ferred from one container to an other by gravity flow, siphoning, or pumping. 9. Mixtures containing trichloro ethylene should be stored in closed containers and used with the same precautions as for pure trichloro ethylene. 10. Trichloroethylene vapors are heavier than air and tend to collect in poorly ventilated pockets and other low places. For this reason, containers should not be stored in pits, basements, or unventilated areas. Handling 11. Trichloroethylene should not be used in open pans or for de greasing in makeshift or homemade apparatus. The design of degreasing equipment should be undertaken only by a competent engineer. 12. Most trichloroethylene de greasing and cleaning is done at a relatively high temperature, usually at or near the boiling point of the solvent, and such high temperature processes require more elaborate control than those at or below room temperature. When trichloroethyl ene is mixed with a flammable, less volatile solvent, the flash point should be regularly tested to make certain a flammable mixture has not been created due to evapora tion. 13. Modern vapor degreasing, dry cleaning, extraction, and other units designed by responsible equip ment manufacturers are constructed so that concentrations of vapor in the vicinity are consistently within the accepted safe limits provided that the equipment is correctly operated. It is extremely important, however, that the operators be thoroughly instructed in the use of the unit and be carefully super vised. 14. It excessive concentrations of trichloroethylene are suspected, a competent technician should check the equipment lor mechani cal condition and review the operat ing practices used. 15. Workers should be thorough ly informed of the hazards that may result from improper handling of trichloroethylene. They should be cautioned to prevent spills and thoroughly instructed regarding proper action to take in case they occur. Each employee should know what to do in an emergency and should be fully informed as to firstaid measures. Personal protective equipment 16. Where exposure to trichloro ethylene may occur, for example, from spills, workers should wear personal protective equipment to guard against harmful contact with the material or its vapors. Gloves and aprons should be worn to pro tect the skin from direct contact. Chemical goggles or face shields and safety-toe shoes or boots should be worn. All items of personal pro tective equipment should be made of material that is resistant to the solvent action of tricholorocthylenc. 17. Work in a confined area re quires the use of respiratory pro tective equipment approved by the U.S. Bureau of Mines for the spe cific exposure. 18. A gas mask with canister is adequate only when tests show that the amount of trichloroethylene vapor in the atmosphere is less than 2 per cent by volume and the oxygen content is not less than 16 per cent. 19. If an emergency requires a worker to enter a heavily contam inated area, such as a tank, he should wear either a hose mask with blower or a self-contained breathing apparatus, together with a rescue harness to which a lifeline is at tached. Another worker, similarly equipped, should be stationed out side the tank to tend the lifeline and if necessary to assist the man in side. Ventilation 20. Operations employing tri- cloroethylene should always be conducted in well-ventilated areas. When a ventilating system is in stalled, an effort should be made to base tile natural air current'- in the vicinity assist rather than op pose the mechanical ventilation The system should draw the vapor away from the operator rather than through his breathing zone. 21 The discharge from mechan ical ventilating systems should be placed far enough from the building so that the exhausted vapors will not create a public nuisance not re-enter the building to contaminate any area. 22. Specific ventilation require ments depend on the type of equip ment used: a. For the vapor degreasing- of metals, open machines are used in which the vapor level is controlled b> heat input and cooling coils, which es tablish a vapor "ceiling " Such vapor degreasing units should al ways be installed in locations free from draft conditions and should he ventilated by horizontal slot ex hausts. b. Partially enclosed equipment has been designed for the use of tri chloroethylene in the dry cleaning industry. This equipment recycles a great part of the solvent vapor to a condenser, thereby minimizing exposure of the worker. A correctly designed machine will prevent seep age of solvent liquid and vapor dur ing the cleaning operation. Par tialis closed systems are also used tor metal degreasing operations in some conveyor type vapor units c. Extraction and other chemical processes using trichloroethylene are done in totally enclosed units. Fire hazards 23. Underwriters' Laboratories-1 classes trichloroethylene as nonflam mable at ordinary temperatures and moderately flammable at elevated temperatures. However, its vapors may be decomposed to toxic and corrosive substances if exposed to high temperatures, such as those encountered in open flames, or to radiation from arc welding or cut ting operations. 24. Trichloroethylene is some times mixed with flammable sol vents to produce less flammable mixtures or to increase solvent power. If the flammable solvent is less volatile than trichloroethylene, the trichloroethylene will evaporate more quickly, changing the compo sition of the mixture and resulting in an increasingly flammable mix ture. On the other hand, if a flam- SL 035393 rmtblc solvent more volatile than trichloroethylene is mixed with trichloroethylene, the vapors from the mixture may be highly flam mable. Symptoms of poisoning 25. In sufficiently high concen trations, trichloroethylene has nar cotic properties similar to but slight ly less marked than chloroform. Prolonged exposure or frequent short exposures to concentrations higher than 200 parts per million by volume (ppm) may injure the nervous system and possibly the liver. Concentrations moderately higher than 200 ppm may also cause nausea, dizziness, headache, and lethargy. These symptoms, however, do not necessarily indi cate systemic poisoning. Repeated inhalation of trichloroethylene va pors may lead to craving and habit uation. Concentrations of 160 ppm are just detectable by their odor, and inhalation of 1,300 ppm for six minutes is said to cause vertigo, pressure in the head, fatigue, and irritation of the mucous membranes. 26. Ingestion of trichloroethyl ene may cause toxic effects similar to those produced by excessive in halation. Contact of trichloroethyl ene with the skin causes first irrita tion and later numbness. Prolonged skin contact may cause formation of blisters and, in addition, remove the protective fat layer of the skin and predispose to secondary infec tions and eczema. First aid 27. A person showing evidence of intoxication from the inhalation of trichloroethylene vapors should be moved promptly to fresh air. If breathing has stopped, artificial res piration should be started at once and should be continued until a physician arrives. 28. In case of skin contact, the contaminated clothing should be removed immediately and the af fected areas washed thoroughly with warm water and soap. A phy sician should be consulted because systemic poisoning or skin irritation (dermatitis) may result from such an exposure. 29. If trichloroethylene should get into the eyes, they should be gently irrigated for at least 15 minutes with large quantities of water Irrigation should be started immediately. In all such cases, medical attention should be ob tained without delay. Threshold limit values 30. The threshold limit value -- the time-weighted average concen tration believed safe for continuous exposure during a normal work day--has been established by the American Conference of Govern mental Industrial Hygienists4 at 100 ppm for trichloroethylene. Samples of air should be taken wherever exposure to trichloro ethylene is known or suspected. In most states, advice and assistance may be obtained from the industrial hygiene division of the state health or labor department. Physical examinations 31. Every applicant for work that may involve exposure to tricholoroethylene should be given a pre-employment physical exami nation. Subsequently, a complete physical examination should be made at least once a year unless the degree of exposure indicates the need for more frequent checking. 32. Generally, individuals who are heavy users of alcoholic liquors, those who are markedly overweight or underweight, and those with evidence of disease of the lungs, liver, kidneys, or heart or with chronic skin conditions should not be exposed to trichloroethylene. Waste disposal 33. Federal, state, and local reg ulations with regard to waste dis posal should be known and fol lowed. Waste should not under any condition be emptied into a munici pal sewer system. The most de sirable treatment for any trichloro ethylene waste is to recover the solvents from it m a properly de signed and operated still. This pro cedure can essentially eliminate waste-disposal problems. ACKNOWLEDGMENT The present revision of this data sheet was prepared by the Industrial Depart ment of the National Safety Council and reviewed by members of the Technical Publications Committee of the Council's Chemical Section. REFERENCES 1. Manufacturing Chemists' Associa tion. 1825 Connecticut Ave., NW, Wash ington, D.C. 20009 Guide io Precanliotiary Labellay of Hazardous Mateiials. Manual 1.-1. 1961. 2. Naiional Safely Council, 425 North Michigan Ave,, Chicago 60611. Vapor Degreascrs Data Sheet 429. 1956, 3. Underwriters' Laboratories. Inc.. 207 East Ohio St.. Chicago 60611. Gas and Oil Equipment List. November 1962. 4 American Conference of Govern mental Industrial Hygienists, 1014 Broad way. Cmcinnaii 45202. Threshold Limit Values for 1963. BIBLIOGRAPHY American Industrial Hygiene Associa tion. 14125 Prevosl, Detroit 48227. Tri chloroethylene. Hygienic Guide, 1956. American National Standards Insti tute, 1430 Broadway, New York. Allcneuhle Concentration of Trichloroethylene Z37.19. Association of Casualty and Surely Companies, Accident Prevention Depart ment. 110 William St.. New York 10038 Trichloroethylene- Chemical Hazards In formation Series C-8, rev. Apr. 1961. Manufacturing Chemists' Association, 1825 Connecticut Ave., NW , Washing ton. D.C. 20009. Trichloroethylene. Chemical Safety Data Sheet SD-14, 1956. US. Bureau of Mines, 4800 Forbes Ave., Pittsburgh 15213. Flammahtltty of Trichloroethylene. Report of Investiga tion 6190. 1963, Williams. Jonathan W " I he Toxicity of Trichloroethylene" Journal of Occu pational Medicine, I'549 (Oct. 1959). Witheredge. W N., and Herbert T Walworth "Ventilation of a 'Trichloro ethylene Degreaser " Journal of Indus trial Hygiene and 7 oak ologw 22 :175-187 I May 1940) si 35394