FLUORIDE ACTION NETWORK PESTICIDE PROJECT
Return to FAN's Pesticide Homepage
Return to Dichlorotetrafluoroethane Index Page
Dichlorotetrafluoroethane. Occupational Safety and Health Guideline. OSHA.
From: http://www.osha-slc.gov/SLTC/healthguidelines/dichlorotetrafluoroethane/recognition.html
OCCUPATIONAL SAFETY AND HEALTH GUIDELINE FOR DICHLOROTETRAFLUOROETHANE (REFRIGERANT 114)
INTRODUCTION
This guideline summarizes pertinent information about dichlorotetrafluoroethane for workers and employers as well as for physicians, industrial hygienists, and other occupational safety and health professionals who may need such information to conduct effective occupational safety and health programs. Recommendations may be superseded by new developments in these fields; readers are therefore advised to regard these recommendations as general guidelines and to determine whether new information is available.
SUBSTANCE IDENTIFICATION
* Formula
C(2)Cl(2)F(4)
* Structure
ClF(2)C-CClF(2)
* Synonyms
Fluorocarbon 114, 1,2-dichlorotetrafluoroethane, freon 114, refrigerant 114, halon 242, cryofluorane, FC-114
* Identifiers
1. CAS No.: 76-14-2
2. RTECS No.: KI1101000
3. DOT UN: 1958 12
4. DOT label: Nonflammable Gas
* Appearance and odor
Dichlorotetrafluoroethane is a gas with a sweetish, chloroform-like odor; when pressurized or kept cold, it is a colorless liquid.
CHEMICAL AND PHYSICAL PROPERTIES
* Physical data
1. Molecular weight: 170.9
2. Boiling point (at 760 mm Hg): 3.5 degrees C (38.4 degrees F)
3. Specific gravity (water = 1): 1.5 at 0 degrees C (32 degrees F)
4. Vapor density: 5.9
5. Melting point: -94 degrees C (-137 degrees F)
6. Vapor pressure at 20 degrees C (68 degrees F): 1444 mm Hg
7. Solubility: Dichlorotetrafluoroethane is practically insoluble in water at 20 degrees C (68 degrees F) but is soluble in alcohol and ether.
8. Evaporation rate: Data not available.
* Reactivity
1. Conditions contributing to instability: Heat.
2. Incompatibilities: Contact between dichlorotetrafluoroethane and alkalies or alkaline earth metals such as sodium or potassium with calcium, zinc, magnesium, or powdered aluminum should be avoided.
3. Hazardous decomposition products: Toxic gases and vapors such as hydrogen chloride, phosgene, hydrogen fluoride, and carbonyl fluoride may be released in a fire involving dichlorotetrafluoroethane.
4. Special precautions: None reported.
* Flammability
Dichlorotetrafluoroethane is a nonflammable gas at room temperature.
The National Fire Protection Association has not assigned a flammability rating to dichlorotetrafluoroethane. Other sources rate dichlorotetrafluoroethane as a minimal fire hazard when this substance is exposed to heat or open flame.
1. Flash point: Not applicable.
2. Autoignition temperature: Not applicable.
3. Flammable limits in air: Not applicable.
4. Extinguishant: Use extinguishant suitable for materials in surrounding fire. For small fires use dry chemical or carbon dioxide. Use water spray, fog, or regular foam to fight large fires.
Fires involving dichlorotetrafluoroethane should be fought upwind from the maximum distance possible. Keep unnecessary people away; isolate the hazard area and deny entry. Isolate the area for 1/2 mile in all directions if a tank, rail car, or tank truck is involved in the fire. Emergency personnel should stay out of low areas. Cylinders of dichlorotetrafluoroethane may explode in the heat of the fire and should be moved from the fire area if it is possible to do so safely. If this is not possible, cool fire exposed containers from the sides with water until well after the fire is out. Stay away from the ends of containers. Personnel should withdraw immediately if a rising sound from a venting safety device is heard or if there is discoloration of a container due to fire. Firefighters should wear a full set of protective clothing and self-contained breathing apparatus when fighting fires involving dichlorotetrafluoroethane.
EXPOSURE LIMITS
The current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for dichlorotetrafluoroethane is 1000 parts per million (ppm) parts of air (7000 milligrams per cubic meter (mg/m(3))) as an 8-hour time-weighted average (TWA) concentration [29 CFR 1910.1000, Table Z-1].
* NIOSH REL
The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limit (REL) for dichlorotetrafluoroethane of 1000 ppm (7000 mg/m(3)) as a TWA for up to a 10-hour workday and a 40-hour workweek [NIOSH 1992].
* ACGIH TLV
The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned dichlorotetrafluoroethane a threshold limit value (TLV) of 1000 ppm (6990 mg/m(3)) as a TWA for a normal 8-hour workday and a 40-hour workweek [ACGIH 1994, p. 19].
* Rationale for Limits
The NIOSH limit is based on the risk of respiratory irritation, asphyxia at high concentrations [NIOSH 1992].
The ACGIH limit is based on the risk of systemic toxicity and cardiac sensitization [ACGIH 1991, p. 444].
* Routes of Exposure Exposure to dichlorotetrafluoroethane can occur through inhalation, ingestion, and eye or skin contact [Sittig 1991].
* Summary of toxicology
1. Effects on Animals: dichlorotetrafluoroethane is a cardiac sensitizer, an asphyxiant, and a weak narcotic at extremely high concentrations [ACGIH 1991]. Dogs exposed to 200,000 ppm of dichlorotetrafluoroethane for 16 hours died, but exposures at this level for 8 hours caused tremor and convulsions [Hathaway et al. 1991]. Serious arrhythmia occurred in one of 12 dogs exposed once to 25,000 ppm of dichlorotetrafluoroethane and given intravenous epinephrine. Dichlorotetrafluoroethane is reported to reduce pulmonary compliance and act as a bronchoconstrictor [ACGIH 1991]. Guinea pigs exposed to a dichlorotetrafluoroethane concentration of 47,000 ppm developed respiratory irritation [Hathaway et al. 1991]. Repeated exposure to sprayed dichlorotetrafluoroethane caused localized skin inflammation in rats and irritation of the eyes of rabbits [ACGIH 1991].
2. Effects on Humans: Dichlorotetrafluoroethane is an asphyxiant at extremely high concentrations and also produces narcotic symptoms at these levels. The cardiac sensitization potential of dichlorotetrafluoroethane is considered moderate; sniffing aerosols of other fluorochlorinated hydrocarbons has caused cardiac arrest, although dichlorotetrafluoroethane has not specifically been implicated in such deaths [Hathaway et al. 1991]. Contact of the skin or eyes with the liquid can cause frostbite or burns [Hathaway et al. 1991].
* Signs and symptoms of exposure
1. Acute exposure: Lightheadedness, giddiness, disorientation, shortness of breath, and cardiac irregularities may occur as a result of exposure to high concentrations. Contact of the skin or eyes with the liquid can cause frostbite or burns [Genium 1993].
2. Chronic exposure: No signs or symptoms of chronic exposure to dichlorotetrafluoroethane have been reported in humans.
* Emergency medical procedures: [NIOSH to supply]
5. Rescue: Remove an incapacitated worker from further exposure and implement appropriate emergency procedures (e.g., those listed on the Material Safety Data Sheet required by OSHA's Hazard Communication Standard [29 CFR 1910.1200]). All workers should be familiar with emergency procedures, the location and proper use of emergency equipment, and methods of protecting themselves during rescue operations.
EXPOSURE SOURCES AND CONTROL METHODS
The following operations may involve dichlorotetrafluoroethane and lead to worker exposures to this substance:
* The manufacture and transportation of dichlorotetrafluoroethane
* Used in nonflammable aerosol propellants; as a refrigerant in industrial cooling and air conditioning systems
* Used as a solvent, diluent, and degreaser in the electronics and chemical industries; as a blowing agent in manufacture of cellular polymers; and as an extractant for volatile substances
* Used in the manufacture of explosives, as a component of dielectric fluid, and as a foaming agent in fire extinguishers
Methods that are effective in controlling worker exposures to dichlorotetrafluoroethane, depending on the feasibility of implementation, are as follows:
* Process enclosure
* Local exhaust ventilation
* General dilution ventilation
* Personal protective equipment
Workers responding to a release or potential release of a hazardous substance must be protected as required by paragraph (q) of OSHA's Hazardous Waste Operations and Emergency Response Standard [29 CFR 1910.120].
Good sources of information about control methods are as follows:
1. ACGIH [1992]. Industrial ventilation--a manual of recommended practice. 21st ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.
2. Burton DJ [1986]. Industrial ventilation--a self study companion. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.
3. Alden JL, Kane JM [1982]. Design of industrial ventilation systems. New York, NY: Industrial Press, Inc.
4. Wadden RA, Scheff PA [1987]. Engineering design for control of workplace hazards. New York, NY: McGraw-Hill.
5. Plog BA [1988]. Fundamentals of industrial hygiene. Chicago, IL: National Safety Council.
OSHA is currently developing requirements for medical surveillance. When these requirements are promulgated, readers should refer to them for additional information and to determine whether employers whose employees are exposed to dichlorotetrafluoroethane are required to implement medical surveillance procedures.
* Medical Screening
Workers who may be exposed to chemical hazards should be monitored in a systematic program of medical surveillance that is intended to prevent occupational injury and disease. The program should include education of employers and workers about work-related hazards, early detection of adverse health effects, and referral of workers for diagnosis and treatment. The occurrence of disease or other work-related adverse health effects should prompt immediate evaluation of primary preventive measures (e.g., industrial hygiene monitoring, engineering controls, and personal protective equipment). A medical surveillance program is intended to supplement, not replace, such measures. To detect and control work-related health effects, medical evaluations should be performed (1) before job placement, (2) periodically during the term of employment, and (3) at the time of job transfer or termination.
* Preplacement medical evaluation
Before a worker is placed in a job with a potential for exposure to dichlorotetrafluoroethane, a licensed health care professional should evaluate and document the worker's baseline health status with thorough medical, environmental, and occupational histories, a physical examination, and physiologic and laboratory tests appropriate for the anticipated occupational risks. These should concentrate on the function and integrity of the respiratory system and cardiovascular system. Medical surveillance for respiratory disease should be conducted using the principles and methods recommended by the American Thoracic Society.
A preplacement medical evaluation is recommended to assess medical conditions that may be aggravated or may result in increased risk when a worker is exposed to dichlorotetrafluoroethane at or below the prescribed exposure limit. The health care professional should consider the probable frequency, intensity, and duration of exposure as well as the nature and degree of any applicable medical condition. Such conditions (which should not be regarded as absolute contraindications to job placement) include a history and other findings consistent with diseases of the respiratory system or cardiovascular system.
* Periodic medical evaluations
Occupational health interviews and physical examinations should be performed at regular intervals during the employment period, as mandated by any applicable Federal, State, or local standard. Where no standard exists and the hazard is minimal, evaluations should be conducted every 3 to 5 years or as frequently as recommended by an experienced occupational health physician. Additional examinations may be necessary if a worker develops symptoms attributable to dichlorotetrafluoroethane exposure. The interviews, examinations, and medical screening tests should focus on identifying the adverse effects of dichlorotetrafluoroethane on the respiratory system or cardiovascular system. Current health status should be compared with the baseline health status of the individual worker or with expected values for a suitable reference population.
* Termination medical evaluations
The medical, environmental, and occupational history interviews, the physical examination, and selected physiologic or laboratory tests that were conducted at the time of placement should be repeated at the time of job transfer or termination to determine the worker's medical status at the end of his or her employment. Any changes in the worker's health status should be compared with those expected for a suitable reference population.
* Biological monitoring
Biological monitoring involves sampling and analyzing body tissues or fluids to provide an index of exposure to a toxic substance or metabolite. No biological monitoring test acceptable for routine use has yet been developed for dichlorotetrafluoroethane.
WORKPLACE MONITORING AND MEASUREMENT
Determination of a worker's exposure to airborne dichlorotetrafluoroethane is made using a two charcoal tubes in series (first tube 400/200 mg sections, second tube 100/50 mg sections, both tubes 20/40 mesh). Samples are collected at a maximum flow rate of 0.05 liter/minute until a maximum collection volume of 4 liters is reached. The sample is then treated with methylene chloride. Analysis is conducted by gas chromatography using a flame ionization detector (GC/FID). This method is fully validated and is described in the OSHA Computerized Information System [OSHA 1994] and in NIOSH Method No. 1018 [NIOSH 1994b].
If dichlorotetrafluoroethane contacts the skin, workers should flush the affected areas immediately with plenty of tepid water.
Clothing contaminated with dichlorotetrafluoroethane should be removed immediately, and provisions should be made for the safe removal of the chemical from the clothing. Persons laundering the clothes should be informed of the hazardous properties of dichlorotetrafluoroethane.
A worker who handles dichlorotetrafluoroethane should thoroughly wash hands, forearms, and face with soap and water before eating, using tobacco products, using toilet facilities, applying cosmetics, or taking medication.
Workers should not eat, drink, use tobacco products, apply cosmetics, or take medication in areas where dichlorotetrafluoroethane or a solution containing dichlorotetrafluoroethane is handled, processed, or stored.
Dichlorotetrafluoroethane should be stored in a cool, dry, well-ventilated area in tightly sealed containers that are labeled in accordance with OSHA's Hazard Communication Standard [29 CFR 1910.1200]. Containers of dichlorotetrafluoroethane should be protected from physical damage and heat or ignition sources, and should be stored separately from alkalies or alkaline earth metals such as sodium or potassium with calcium, zinc, magnesium, or powdered aluminum.
In the event of a spill or leak involving dichlorotetrafluoroethane, persons not wearing protective equipment and clothing should be restricted from contaminated areas until cleanup has been completed. The following steps should be undertaken following a spill or leak:
1. Notify safety personnel.
2. Remove all sources of heat and ignition.
3. Ventilate the area of the spill or leak.
4. Stop leak if this can be done without risk.
5. If the source of the leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place and repair the cylinder or allow the cylinder to empty.
6. If the liquid is spilled or leaked, allow it to vaporize.
SPECIAL REQUIREMENTS
U.S. Environmental Protection Agency (EPA) requirements for emergency planning, reportable quantities of hazardous releases, community right-to-know, and hazardous waste management may change over time. Users are therefore advised to determine periodically whether new information is available.
* Emergency planning requirements
Dichlorotetrafluoroethane is not subject to EPA emergency planning requirements under the Superfund Amendments and Reauthorization Act (SARA) (Title III) in 42 USC 11022.
* Reportable quantity requirements for hazardous releases
A hazardous substance release is defined by EPA as any spilling, leaking, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment (including the abandonment or discarding of contaminated containers) of hazardous substances. In the event of a release that is above the reportable quantity for that chemical, employers are required to notify the proper Federal, State, and local authorities [40 CFR 355.40].
Employers are not required by the emergency release notification provisions in 40 CFR Part 355.40 to notify the National Response Center of an accidental release of dichlorotetrafluoroethane; there is no reportable quantity for this substance.
* Community right-to-know requirements
Employers are not required by EPA in 40 CFR Part 372.30 to submit a Toxic Chemical Release Inventory form (Form R) to EPA reporting the amount of dichlorotetrafluoroethane emitted or released from their facility annually.
* Hazardous waste management requirements
EPA considers a waste to be hazardous if it exhibits any of the following characteristics: ignitability, corrosivity, reactivity, or toxicity as defined in 40 CFR 261.21-261.24. Under the Resource Conservation and Recovery Act (RCRA) [40 USC 6901 et seq.], EPA has specifically listed many chemical wastes as hazardous. Although dichlorotetrafluoroethane is not specifically listed as a hazardous waste under RCRA, EPA requires employers to treat waste as hazardous if it exhibits any of the characteristics discussed above.
Providing detailed information about the removal and disposal of specific chemicals is beyond the scope of this guideline. The U.S. Department of Transportation, EPA, and State and local regulations should be followed to ensure that removal, transport, and disposal of this substance are conducted in accordance with existing regulations. To be certain that chemical waste disposal meets EPA regulatory requirements, employers should address any questions to the RCRA hotline at (703) 412-9810 (in the Washington, D.C. area) or toll-free at (800) 424-9346 (outside Washington, D.C.). In addition, relevant State and local authorities should be contacted for information on any requirements they may have for the waste removal and disposal of this substance.
* Conditions for respirator use
Good industrial hygiene practice requires that engineering controls be used where feasible to reduce workplace concentrations of hazardous materials to the prescribed exposure limit. However, some situations may require the use of respirators to control exposure. Respirators must be worn if the ambient concentration of dichlorotetrafluoroethane exceeds prescribed exposure limits. Respirators may be used (1) before engineering controls have been installed, (2) during work operations such as maintenance or repair activities that involve unknown exposures, (3) during operations that require entry into tanks or closed vessels, and (4) during emergencies. Workers should only use respirators that have been approved by NIOSH and the Mine Safety and Health Administration (MSHA).
* Respiratory protection program
Employers should institute a complete respiratory protection program that, at a minimum, complies with the requirements of OSHA's Respiratory Protection Standard [29 CFR 1910.134]. Such a program must include respirator selection, an evaluation of the worker's ability to perform the work while wearing a respirator, the regular training of personnel, respirator fit testing, periodic workplace monitoring, and regular respirator maintenance, inspection, and cleaning. The implementation of an adequate respiratory protection program (including selection of the correct respirator) requires that a knowledgeable person be in charge of the program and that the program be evaluated regularly. For additional information on the selection and use of respirators and on the medical screening of respirator users, consult the latest edition of the NIOSH Respirator Decision Logic [NIOSH 1987b] and the NIOSH Guide to Industrial Respiratory Protection [NIOSH 1987a].
Workers should use appropriate personal protective clothing and equipment that must be carefully selected, used, and maintained to be effective in preventing skin contact with dichlorotetrafluoroethane. The selection of the appropriate personal protective equipment (PPE) (e.g., gloves, sleeves, encapsulating suits) should be based on the extent of the worker's potential exposure to dichlorotetrafluoroethane. There are no published reports on the resistance of various materials to permeation by dichlorotetrafluoroethane.
To evaluate the use of PPE materials with dichlorotetrafluoroethane, users should consult the best available performance data and manufacturers' recommendations. Significant differences have been demonstrated in the chemical resistance of generically similar PPE materials (e.g., butyl) produced by different manufacturers. In addition, the chemical resistance of a mixture may be significantly different from that of any of its neat components.
Any chemical-resistant clothing that is used should be periodically evaluated to determine its effectiveness in preventing dermal contact. Safety showers and eye wash stations should be located close to operations that involve dichlorotetrafluoroethane.
Splash-proof chemical safety goggles or face shields (20 to 30 cm long, minimum) should be worn during any operation in which a solvent, caustic, or other toxic substance may be splashed into the eyes.
In addition to the possible need for wearing protective outer apparel (e.g., aprons, encapsulating suits), workers should wear work uniforms, coveralls, or similar full-body coverings that are laundered each day. Employers should provide lockers or other closed areas to store work and street clothing separately. Employers should collect work clothing at the end of each work shift and provide for its laundering. Laundry personnel should be informed about the potential hazards of handling contaminated clothing and instructed about measures to minimize their health risk.
Protective clothing should be kept free of oil and grease and should be inspected and maintained regularly to preserve its effectiveness.
Protective clothing may interfere with the body's heat dissipation, especially during hot weather or during work in hot or poorly ventilated work environments.
REFERENCES
ACGIH [1991]. Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.
ACGIH [1994]. 1994-1995 Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.
ATS [1987]. Standardization of spirometry -- 1987 update. American Thoracic Society. Am Rev Respir Dis 136:1285-1296.
CFR. Code of Federal regulations. Washington, DC: U.S. Government Printing Office, Office of the Federal Register.
DOT [1993]. 1993 Emergency response guidebook, guide 12. Washington, DC: U.S. Department of Transportation, Office of Hazardous Materials Transportation, Research and Special Programs Administration.
Genium [1993]. Material safety data sheet No. 572. Schenectady, NY: Genium Publishing Corporation.
Hathaway GJ, Proctor NH, Hughes JP, and Fischman ML [1991]. Proctor and Hughes' chemical hazards of the workplace. 3rd ed. New York, NY: Van Nostrand Reinhold.
Lewis RJ, ed. [1993]. Hawley's condensed chemical dictionary. 12th ed. New York, NY: Van Nostrand Reinhold Company.
Mickelsen RL, Hall RC [1987]. A breakthrough time comparison of nitrile and neoprene glove materials produced by different glove manufacturers. Am Ind Hyg Assoc J 48(11): 941-947.
Mickelsen RL, Hall RC, Chern RT, Myers JR [1991]. Evaluation of a simple weight-loss method for determining the permeation of organic liquids through rubber films. Am Ind Hyg Assoc J 52(10): 445-447.
NIOSH [1987a]. NIOSH guide to industrial respiratory protection. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 87-116.
NIOSH [1987b]. NIOSH respirator decision logic. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 87-108.
NIOSH [1992]. Recommendations for occupational safety and health: Compendium of policy documents and statements. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 92-100.
NIOSH [1994a]. NIOSH pocket guide to chemical hazards. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-116.
NIOSH [1994b]. NIOSH manual of analytical methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113.
NIOSH [1995]. Registry of toxic effects of chemical substances: Dichlorotetrafluoroethane. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, Division of Standards Development and Technology Transfer, Technical Information Branch.
NJDH [1992]. Hazardous substance fact sheet: Dichlorotetrafluoroethane. Trenton, NJ: New Jersey Department of Health.
NLM [1995]. Hazardous substances data bank: Dichlorotetrafluoroethane. Bethesda, MD: National Library of Medicine.
OSHA [1994]. Computerized information system. Washington, DC: U.S. Department of Labor, Occupational Safety and Health Administration.
Sax NI, Lewis RJ [1989]. Dangerous properties of industrial materials. 7th ed. New York, NY: Van Nostrand Reinhold Company.
Sittig M [1991]. Handbook of toxic and hazardous chemicals. 3rd ed. Park Ridge, NJ: Noyes Publications.
USC. United States code. Washington. DC: U.S. Government Printing Office.
Windholz M, ed. [1983]. Merck Index 10th ed. Rahway, NJ: Merck & Company.