The National Institute fo r Occupational Safety and Health (NIOSH) recommends that worker exposure to carbon tetrachloride in the workplace be controlled by adherence to the follow ing sections. The standard is designed to protect the health and provide fo r the safety of workers for up to a 10-hour workday, 40-hour workweek over a working lifetim e. Compliance w ith all sections of the standard should prevent the adverse effects currently reported from exposure to carbon tetrachloride in the workplace and m aterially reduce the risk of cancer from occupational exposure to carbon tetrachloride. The standard is meas urable by techniques tha t are valid, reproduc ible, and available. Sufficient technology exists to perm it com pliance w ith the recommended standard. The standard w ill be subject to fu r the r review and revision as necessary. " Occu pational exposure to carbon te trach lorid e" is defined as exposure to carbon tetrachloride in any establishm ent where carbon tetrachloride is used, m anufactured, or stored. Exposure to carbon tetrachloride under any of the above conditions w ill require adherence to all of the follow ing sections.

# Section 1 -Environmental (Workplace Air)
Carbon tetrachloride shall be controlled in the workplace so that the concentration of carbon tetrachloride is not greater than 2 ppm (12.6mg m3) of breathing zone air in a 45 liter a ir sample taken over a period not to exceed 1 hour in duration.
Procedures for sam pling and analysis of carbon tetrachloride in air shall be as provided in Appendices I and II, or by any method shown to be equivalent in precision, accuracy, and sensitivity to the methods specified.
Section 2 -Medical (a) Comprehensive preplacement and an nual medical examinations shall be made avail able to all workers exposed to carbon te tra chloride unless a different frequency is in d i cated by professional medical judgm ent based on such factors as emergencies, variations in work periods, and preexisting health status of individual workers.
(b) These examinations shall include, but shall not be lim ited to:
(1) A comprehensive and interim med ical and work history to include occurrence of nausea, vom iting, visual disturbances, and use of alcohol and barbiturates.
(2) A comprehensive medical examina tion, giving particular attention to kidneys, eyes (black and white and color visual fields), and appropriate tests of liver function.
(3) An evaluation of the w orker's phys ical a b ility to safely wear a respirator.
(c) Employees shall be counseled regard ing the increased hazards of working w ith car bon tetrachloride resulting from use of alcohol and barbiturates.
(d) Medical records shall be maintained for all persons employed in work involving occupational exposure to carbon tetrachloride fo r at least 30 years after the individu al's em ploym ent is term inated. The medical rep resentatives of the Secretary of Health, Educa tion, and Welfare, of the Secretary of Labor, of the employer, and of the employee or form er employee shall have access to these records.
(e) Initial exam inations for presently em ployed workers shall be offered w ithin 6 months of the prom ulgation of a standard in corporating these recommendations. (b) In areas where there is occupational exposure to carbon tetrachloride, the follow ing w arning sign shall be posted in readily visible locations, particularly at the entrances to the area.

# DANGER! EXTREME HEALTH HAZARD CANCER-SUSPECT AGENT USED IN THIS AREA UNAUTHORIZED PERSONS KEEP OUT
The sign shall be printed both in English and in the predom inant language of non-Englishspeaking workers, if any, unless employers use other equally effective means to ensure that these workers know the hazards associated w ith carbon tetrachloride and the locations of areas in which there is occupational exposure to carbon tetrachloride. Employers shall en sure that illiterate workers also know these hazards and the locations of these areas.

# Section 4 -Personal Protective Equipment
and Protective Clothing (a) Protective Clothing (1) Coveralls or other full-body protec tive clothing shall be worn in areas where there is occupational exposure to carbon tetrachlo ride. Protective clothing shall be changed at least daily at the end of the sh ift and more frequently if it should become grossly con tam inated.
(2) Impervious gloves, aprons, and footwear shall be worn at operations where carbon tetrachloride may contact the skin.
(3) Eye protective devices shall be provided by the employer and used by the employees where contact of carbon te tra chloride w ith eyes is likely. Selection, use, and maintenance of eye protective equipm ent shall follow the Standard Practice fo r Occupa tional and Educational Eye and Face Protec tion, ANSI Z87.1-1968. Unless eye protection is afforded by a respirator hood or facepiece, protective goggles or a face shield shall be worn at operations where there is danger of contact of the eyes w ith wet m aterials contain ing carbon, tetrachloride because of spills, splashes, or excessive vapors in the air.
(4) The em ployer shall ensure that all personal protective devices are inspected reg ularly and maintained in clean and satisfactory working condition.
(5) Work clothing may not be taken home by employees. The em ployer shall pro vide for maintenance and laundering of pro tective clothing.
(6)The employer shall ensure that pre cautions necessary to protect laundry person nel are taken while soiled protective clothing is being laundered.
(7) The employer shall ensure that carbon tetrachloride is not discharged into m unicipal waste treatm ent systems or the com m unity air.
(b) Respiratory Protection from Carbon Tetrachloride.
Engineering controls shall be used w her ever feasible to m aintain carbon tetrachloride concentrations at or below that recommended in Section 1 above. Compliance with the en vironm ental exposure lim it by the use of respi rators is allowed only when carbon tetrachlo ride concentrations are in excess of the work place environmental lim it because required engineering controls are being installed or tested, when nonroutine maintenance or re pair is being accomplished, or during emer gencies. When a respirator is thus perm itted, it shall be selected and used in accordance w ith the follow ing requirem ents:
(1) For the purpose of determ ining if it is necessary fo r workers to wear respirators, the employer shall measure the concentration of carbon tetrachloride in the workplace in i tia lly and thereafter whenever process, work site, clim ate, or control changes occur which are likely to increase the concentration of car bon tetrachloride.
(2) The em ployer shall ensure that no worker is exposed to carbon tetrachloride above the workplace environm ental lim it be cause of im proper respirator selection, fit, use, or maintenance.
(3) A respiratory protection program meeting the requirem ents of 29 CFR 1910.134 and 30 CFR 11 which incorporates the Am eri can National Standard Practices for Respira tory Protection Z88.2-1969 shall be established and enforced by the employer.
(4) The employer shall provide res pirators in accordance with Table 1-1 and shall ensure that the employee uses the respirator provided anytime the concentration of carbon tetrachloride exceeds the level described in Section 1.
(5) Respirators described in Table 1-1 shall be those approved under the provisions of 29 CFR 1910.134 and 30 CFR 11. (6) The employer shall ensure that res pirators are adequately cleaned, and that em ployees are instructed on the use of respirators assigned to them, th e ir location in the work place, and on how to test for leakage.
(7) Where an emergency may develop which could result in employee injury from carbon tetrachloride, the em ployer shall pro vide an escape device as listed in  At the beginning of em ploym ent or assign ment fo r work in a carbon tetrachloride area, employees w ith occupational exposure to car bon tetrachloride shall be inform ed of the hazards, relevant signs and symptoms of over exposure, appropriate emergency procedures, and proper conditions and precautions for the safe use of carbon tetrachloride.
Instruction shall include, as a m inim um , all inform ation in Appendix III which is a ppli cable to the specific carbon tetrachloride product or material to which there is exposure, as well as inform ation which indicates that carbon tetrachloride causes cancer in experi mental animals. The inform ation shall be posted in the work area and kept on file, read ily accessible to the worker at all places of em ploym ent where carbon tetrachloride is in volved in unit processes and operations.
A continuing educational program shall be instituted to ensure that all workers have cur rent knowledge of job hazards, proper m ain tenance procedures, and cleanup methods, and that they know how to use respiratory protective equipm ent and protective clothing correctly.
Inform ation as specified in Appendix III shall be recorded on the Material Safety Data Sheet or a sim ilar form approved by the Occu pational Safety and Health A dm inistration, US Department of Labor.

# Section 6 -Work Practices (a) Control of Airborne Contamination
Emission of vapors of carbon tetrachloride shall be controlled at the sources of dispersion by means of effective and properly m aintained methods such as fu lly enclosed operations and local exhaust ventilation, under negative pres sure, if possible. No recirculation of control ventilation or process air shall be" perm itted. Other methods may be used if they are shown to effectively control airborne concentrations of carbon tetrachloride w ithin the lim it of the recommended standard.

# (b) Control of Contact w ith Skin and Eyes
(1) Employees working in areas where contact of skin or eyes w ith carbon te tra chloride is possible shall wear full-body pro tective clothing, including neck and head coverings, and gloves, in accord w ith Section 4(a).
(2) Clean protective clothing shall be put on before each work shift.
(3) If, during the shift, the clothing becomes wetted w ith carbon tetrachloride, it shall be removed prom ptly and placed in a special container for garments for decontam i nation or disposal. The employee shall wash the contam inated skin area thoroughly with soap and a copious am ount of water. A com plete shower is preferred after anything but lim ited, m inor contact. Then, clean protective clothing shall be put on before resuming work.
(4) Small areas of skin (principally the hands) contam inated by contact w ith carbon tetrachloride shall be washed im m ediately and thoroughly with an abundance of water. Water shall be easily accessible in the work areas as low-pressure, free-running hose lines or showers.
(5) If carbon tetrachloride comes into contact with the eyes, the eyes should be flushed with a large volume of low-pressure flowing water for at least 15 minutes. Medical attention shall be obtained w ithout delay, but not at the expense of im m ediate and thorough flushing of the eyes.
(c) Procedures for emergencies, including firefighting, shall be established to meet fore seeable events. Necessary emergency equip ment, including appropriate respiratory pro tective devices, shall be kept in readily ac cessible locations. Only self-contained breath ing apparatus w ith positive pressure in the facepiece shall be used in firefighting. Appro priate respirators shall be available for use during evacuation.
(d) Special supervision and care shall be exercised to ensure tha t the exposures of re pair and maintenance personnel to carbon tetrachloride are w ithin the lim it prescribed by this standard.
(e) Prompt cleaning of spills of carbon tetrachloride:
Spills shall be channeled for appro priate treatm ent or collection for disposal. They may not be channeled directly into the m unicipal sanitary sewer system.
(f) General requirements:
(1) Good housekeeping practices shall be observed to prevent or m inim ize contam ina tion of areas and equipm ent and to prevent build-up of such contam ination.
(2) Good personal hygiene practices shall be encouraged.
(3) Equipm ent shall be kept in good repair and free of leaks.
(4) Containers of carbon tetrachloride shall be kept covered insofar as is practical.
(g) A regulated area shall be established and maintained where:
(1) Carbon tetrachloride is m anufac tured, reacted, mixed w ith other substances, repackaged, stored, handled, or used.
(2) Concentrations of carbon tetrachlo ride are in excess of the workplace environ mental lim it in Section 1.
(h) Access to the regulated areas desig nated by Section 6(g) shall be lim ited to authorized persons. A daily roster shall be made of persons authorized to enter; these rosters shall be m aintained fo r 30 years.
(i) Employers shall ensure that before employees leave a regulated area they remove and leave protective clothing at that point.

# Section 7 -Sanitation
(a) Washing Facilities Emergency showers and eye-flushing foun tains with cool water under adequate pressure shall be provided and readily accessible in areas where contact of skin or eyes w ith car bon tetrachloride may occur. This equipm ent shall be frequently inspected and maintained in good working condition.
Showers and washbasins shall be provided in the employees' locker areas. Employers shall ensure that employees exposed to car bon tetrachloride during th e ir work s h ift shall wash before eating or smoking periods taken during the work shift.
(b) Food Facilities Food storage and preparation as well as eating shall be prohibited in areas where car bon tetrachloride is handled, processed, or stored. Eating facilities provided for employees shall be located in areas ventilated in such a manner to ensure that contam ination from carbon tetrachloride is prevented. Surfaces in these areas shall be kept free of carbon tetrachloride. Employers shall ensure that be fore employees enter premises reserved for eating, food storage, or food preparation, they remove protective clothing. Washing facilities should be accessible nearby.
(c) Employees may not smoke in areas where carbon tetrachloride is handled, proc essed, or stored.
(d) Clothing and Locker Room Facilities Locker room fa c ilitie s for employees re quired to change clothing before and after work shall be provided in an area separate and ventilated in such a manner to ensure that contam ination from carbon tetrachloride is non-existent. The fa cilitie s shall provide for the storing of street clothing and clean work clothing separately from soiled work clothing. Showers and washbasins should be located in the locker area to encourage good personal hygiene.
Covered containers should be provided for work clothing discarded at the end of the sh ift or after a contam ination incident. The clothing shall be held in these containers until removed for decontam ination or disposal.

# Section 8 -M onitoring and Recordkeeping Requirements
In any workplace where carbon tetrachlo ride is handled or processed, surveys shall be repeated semi-annually. Requirements set forth below apply to areas in which there is occupational exposure to carbon tetrachloride.
Employers shall m aintain records of work place environm ental exposures to carbon te t rachloride based on the follow ing sampling, analytical, and recording schedules:
(a) In all monitoring, samples representa tive of the exposure in the breathing zone of employees shall be collected by personal samplers.
(b) An adequate num ber of samples shall be taken in order to determ ine the occupa tional exposure of each employee.
(c) The firs t determ ination of employee exposure to carbon tetrachloride shall be completed w ithin 6 months after the prom ul gation of a standard incorporating these recom mendations.
(d) A reevaluation of the exposure of em ployees to carbon tetrachloride shall be made w ithin 30 days after installation of a new process or process changes.
(e) A reevaluation of employee exposure to carbon tetrachloride shall be repeated at 1-week intervals when the airborne concen tration has been found to exceed the recom mended workplace environm ental lim it. In such cases, suitable controls shall be instituted and m onitoring shall continue at 1-week in te r vals until 3 consecutive surveys indicate the adequacy of controls.
(f) Records of all sam pling and analysis of carbon tetrachloride and of m edical exam ina tions shall be maintained for at least 30 years after the individual's em ploym ent is te rm i nated. Records shall indicate the details of (1) type of personal protective devices, if any, in use at the tim e of sampling, and (2) methods of sam pling and analysis used. Each employee shall be able to obtain inform ation on his own exposure. If the employer who has or has had employees w ith occupational exposure to car bon tetrachloride ceases business w ithout a successor, he shall forward th e ir records by registered mail to the Director, National Insti tute for Occupational Safety and Health.

# D E P A R T M E N T O F H E A L T H , E D U C A T I O N , A N D W E L F A R E PUBLIC HEALTH SERVICE C E N T E R F O R D I S E A S E C O N T R O L N A T I O N A L I N S T I T U T E F O R O C C U P A T I O N A L S A F E T Y A N D H E A L T H R O B E R T A . T A F T L A B O R