Disclaimer: The information contained in these guidelines is intended for reference purposes only. It provides a summary of information about chemicals that workers may be exposed to in their workplaces. The information contained in these guidelines is current as of date of publication (September, 1996); recommendations may be superseded by new developments in the field of industrial hygiene. Readers are therefore advised to regard these recomendations as general guidelines and to determine whether new information is available.

OCCUPATIONAL SAFETY AND HEALTH GUIDELINE FOR TEDP (SULFOTEP)

INTRODUCTION

This guideline summarizes pertinent information about tetraethyl dithionopyrophosphate (TEDP), also called sulfotep, 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 Recommendations may be superseded by new developments; readers are therefore advised to regard these recommendations as general guidelines and to determine periodically whether new information is available.

SUBSTANCE IDENTIFICATION

* Formula

(C(2)H(5))(4)P(2)S(2)O(5)

* Structure

(For Structure, see paper copy)

* Synonyms

Sulfotep; thio TEPP; tetraethyl pyrophosphorodithionate; sulfotepp; thio pyrophosphoric acid; tetraethyl ester; Dithion; tetraethyl dithionopyrophosphate; tetraethyl dithiopyrophosphate; Bayer-E-393; Bladafume; Orthio; Lethalaire G-57; Plantfume 103 Smoke Generator.

* Identifiers

1. CAS: 3689-24-5.

2. RTECS: XN4375000.

3. DOT UN: 1704 55.

4. DOT label: Poison.

* Appearance and odor

TEDP is a pale yellow, noncombustible liquid that smells like garlic. TEDP is no longer marketed in the United States.

CHEMICAL AND PHYSICAL PROPERTIES

* Physical data

1. Molecular weight: 322.3.

2. Boiling point (2 torr): 136 degrees to 139 degrees C (277 degrees to 282 degrees F).

3. Specific gravity (water = 1): 1.19 at 25 degrees C (77 degrees F).

4. Vapor density: Data not available.

5. Melting point: 88 degrees C (190.4 degrees F).

6. Vapor pressure at 20 degrees C (68 degrees F): 0.00017 torr.

7. Solubility: Almost insoluble in water; soluble in alcohol and most organic solvents.

8. Evaporation rate: Data not available.

* Reactivity

1. Conditions contributing to instability: None reported.

2. Incompatibilities: Contact of TEDP with strong oxidizers may cause fires and explosions.

3. Hazardous decomposition products: Toxic gases and vapors (such as sulfur dioxide, phosphoric acid mist, and carbon monoxide) may be released in a fire involving TEDP.

4. Special precautions: TEDP attacks iron, some coatings, and some forms of plastic and rubber.

* Flammability

There is no National Fire Protection Association fire hazard rating for TEDP; this substance is not combustible.

1. Flash point: Not applicable.

2. Autoignition temperature: Not applicable.

3. Flammable limits in air: Not applicable.

4. Extinguishant: Use an extinguishant that is suitable for the materials involved in the surrounding fire.

Fires involving TEDP should be fought upwind and from the maximum distance possible. Keep unnecessary people away; isolate hazard area and deny entry. Emergency personnel should stay out of low areas and ventilate closed spaces before entering. Containers of TEDP 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 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. Dikes should be used to contain fire-control water for later disposal. If a tank car or truck is involved in a fire, personnel should isolate an area of a half a mile in all directions. Firefighters should wear a full set of protective clothing, including a self-contained breathing apparatus, when fighting fires involving TEDP. Chemical protective clothing that is specifically recommended for TEDP may not provide thermal protection unless so stated by the clothing manufacturer. Firefighters' protective clothing is not effective against fires involving TEDP.

* Warning properties

No quantitative data are available on the odor threshold for TEDP. For the purpose of respirator selection, this substance is therefore considered to have inadequate odor warning properties.

* Eye irritation properties

TEDP is not known to be an eye irritant.

EXPOSURE LIMITS

The current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for TEDP is 0.2 milligram per cubic meter (mg/m³) of air as an 8-hour time-weighted average (TWA) concentration. The OSHA PEL also bears a "Skin" notation, which indicates that the cutaneous route of exposure (including mucous membranes and eyes) contributes to overall exposure [29 CFR 1910.1000, Table Z-1-A]. The National Institute for Occupational Safety and Health (NIOSH) has not issued a recommended exposure limit (REL) for TEDP; however, NIOSH concurs with the PEL established for this substance by OSHA [NIOSH 1988]. The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned TEDP a threshold limit value (TLV) of 0.2 mg/m³ as a TWA for a normal 8-hour workday and a 40-hour workweek. The ACGIH also assigns a "Skin" notation to TEDP [ACGIH 1991, p. 34]. The ACGIH limit is based on the risk of cholinesterase inhibition associated with exposure to TEDP [ACGIH 1986, p. 541].

HEALTH HAZARD INFORMATION

* Routes of exposure

Exposure to TEDP can occur via inhalation, ingestion, eye or skin contact, and absorption through the skin.

* Summary of toxicology

1. Effects on Animals: TEDP is an inhibitor of plasma and red blood cell cholinesterase that affects the autonomic nervous system in experimental animals. The oral LD(50) in rats is 5 mg/kg, and the LC(50) in the same species is 38 mg/m³ for 4 hours [RTECS 1992]. The dermal LD(50) in rabbits is 20 mg/kg [RTECS 1992]. The acute toxicity of TEDP is estimated to be about half that of parathion [ACGIH 1986, p. 541]. Rats fed a dietary dose of 180 ppm TEDP for 12 weeks became ill and developed observable tissue changes, but those fed 60 ppm for the same period showed no ill effects [ACGIH 1986, p. 541].

2. Effects on Humans: In humans, TEDP is an anticholinesterase agent that inhibits blood and plasma cholinesterase activity. Overexposure to this substance causes inactivation of the enzyme cholinesterase, which leads, in turn, to the buildup of acetylcholine at nerve synapses in the nervous system, skeletal and smooth muscles, and secretory glands [Proctor and Hughes 1978, p. 465]. The effects of overexposure depend on the route of exposure, with ocular and respiratory effects predominating after inhalation, gastrointestinal signs and symptoms after ingestion, and localized effects after skin absorption [Proctor and Hughes 1978, p. 465]. Severe overexposure by any route may cause muscular weakness, respiratory paralysis, coma, heart block, and death [Proctor and Hughes 1978, p. 465]. The patient may recover and be symptom-free within a week, although he or she will be hypersusceptible to the effects of anticholinesterase agents for up to several days after the first exposure. Chronic exposure to small doses of TEDP may lead to the signs and symptoms generally associated with acute overexposure [Proctor and Hughes 1978, p. 465].

* Signs and symptoms of exposure

1. Acute exposure: The signs and symptoms of acute exposure to TEDP may not develop for as long as 12 hours after exposure; signs and symptoms vary by route of exposure. After inhalation, they include ocular effects (blurring, constricted pupils, tearing, and frontal headache) and respiratory effects (wheezing, a sensation of chest tightness, laryngeal spasms, and respiratory distress). After ingestion, effects are primarily gastrointestinal and include nausea, anorexia, vomiting, cramps, and diarrhea. Skin absorption of TEDP leads to localized sweating and muscular twitching in the affected area. The signs and symptoms of TEDP poisoning by any route may progress to giddiness, slurred speech, incoordination, muscle weakness, convulsions, loss of reflexes, coma, respiratory paralysis, and death.

2. Chronic exposure: Repeated exposure to daily doses of TEDP that are too small to cause acute poisoning may result in the development of any of the signs and symptoms described above.

* Emergency procedures:

In the event of an emergency, the rescuer should don appropriate personal protective equipment, remove the victim from further exposure, send for medical assistance, and initiate the following emergency procedures:

1. Eye exposure: If TEDP or a solution containing this substance gets into the eyes, immediately flush the eyes with large amounts of tepid water for a minimum of 15 minutes, lifting the lower and upper lids occasionally. If irritation, pain, swelling, lacrimation, or photophobia persists, get medical attention as soon as possible.

2. Skin exposure: TEDP can be absorbed through the skin in lethal amounts. Therefore, if TEDP or a solution containing this substance contacts the skin, the contaminated skin (including the hair and nails) should immediately be washed vigorously and repeatedly with soap and water. If irritation persists or the signs and symptoms of organophosphate poisoning develop, get medical attention immediately.

3. Inhalation: If TEDP is inhaled, move the victim at once to fresh air and get medical care as soon as possible. If the victim is not breathing, perform cardiopulmonary resuscitation; if breathing is difficult, give oxygen. Keep the victim warm and quiet until medical help arrives.

4. Ingestion: DO NOT INDUCE VOMITING. If TEDP or a solution containing this substance is ingested, give the victim several glasses of water to drink. Get medical help immediately. Keep the victim warm and quiet until medical help arrives.

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 TEDP and lead to worker exposures to this substance:

* Manufacture of TEDP
* Formulation of TEDP-containing insecticides
* Application of TEDP-containing insecticides to flowering plants in commercial greenhouses

Methods that are effective in controlling worker exposures to TEDP, depending on the feasibility of implementation, are

* Process enclosure,
* Local exhaust ventilation,
* General dilution ventilation, and
* Personal protective equipment.

The following publications are good sources of information on control methods:

1. ACGIH [1986]. Industrial ventilation--a manual of recommended practice. 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.

MEDICAL MONITORING

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, placement of workers in jobs that do not jeopardize their safety or health, 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 monitoring program is intended to supplement, not replace, such measures. To place workers effectively and to detect and control work-related health effects, medical evaluations should be performed (1) before job placement, (2) periodically during the period 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 TEDP, 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 blood and central nervous system. Workers who will be assigned to jobs involving exposure to TEDP should have their pre-exposure red blood cell cholinesterase and plasma cholinesterase measured to establish a baseline for biological exposure monitoring.

A preplacement medical evaluation is recommended to assess an individual's suitability for employment at a specific job and to detect and assess medical conditions that may be aggravated or may result in increased risk when a worker is exposed to TEDP 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 blood or central nervous system.

* Periodic medical examinations and biological monitoring

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 TEDP exposure. The interviews, examinations, and medical screening tests should focus on identifying the adverse effects of TEDP on the blood or central nervous 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.

Biological monitoring involves sampling and analyzing body tissues or fluids to provide an index of exposure to a toxic substance or metabolite. The measurement of red blood cell cholinesterase is a nonspecific and qualitative index of exposure to organophosphorus insecticides such as TEDP. Inhibition of red blood cell cholinesterase is an indication of both acute and chronic overexposure to substances in this class of compounds. The systemic effects of exposure to TEDP can be determined by measuring the exposed worker's red blood cell cholinesterase activity and comparing the result with the worker's pre-exposure red blood cell cholinesterase activity. Some sources recommend that the red blood cell cholinesterase activity level be maintained at 70 percent or higher of the individual's pre-exposure baseline and that workers with levels below this biological exposure index be removed from exposure.

* Medical examinations recommended at the time of job transfer or termination

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.

WORKPLACE MONITORING AND MEASUREMENT PROCEDURES

Determination of a worker's exposure to airborne TEDP is made using an OSHA Versatile Sampler (OVS-2) 13-mm XAD-2 tube (270/140 mg sections, 20/60 mesh) with glass fiber filter enclosed. Samples are collected at a maximum flow rate of 1.0 liter per minute until a maximum air volume of 480 liters is collected. The sample is then treated with toluene to extract the TEDP. Analysis is conducted by gas chromatography using a flame photometric detector. This method is described in the OSHA In-House Methods File, U.S. Department of Labor, OSHA Analytical Laboratory, 8660 South Sandy Parkway, Sandy, Utah 84070-6424.

PERSONAL HYGIENE PROCEDURES

Because TEDP can be absorbed through the skin in toxic amounts, workers should immediately and repeatedly wash the affected areas (including the hair, scalp, and fingernails) with soap and water.

Clothing contaminated with TEDP 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 TEDP, particularly its potential to be absorbed through the skin in toxic amounts.

A worker who handles TEDP should thoroughly wash hands, forearms, and face with soap and water before eating, using tobacco products, or using toilet facilities.

Workers should not eat, drink, or use tobacco products in areas where TEDP or a solution containing TEDP is handled, processed, or stored.

STORAGE

TEDP 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. Containers of TEDP should be protected from physical damage and should be stored separately from strong oxidizers, heat, sparks, and open flame. Because containers that formerly contained TEDP may still hold product residues, they should be handled appropriately.

SPILLS AND LEAKS

In the event of a spill or leak involving TEDP, 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. Do not touch the spilled material; stop the leak if it is possible to do so without risk.

2. Notify safety personnel.

3. Remove all sources of heat and ignition.

4. Ventilate the area of the spill or leak.

5. For small dry spills, use a clean shovel and place the material into a clean, dry container; cover and remove the container from the spill area.

6. For small liquid spills, take up with sand or other noncombustible absorbent material and place into closed containers for later disposal.

7. For large liquid spills, build dikes far ahead of the spill to contain the TEDP for later reclamation or disposal.

EMERGENCY PLANNING, COMMUNITY RIGHT-TO-KNOW, AND HAZARDOUS WASTE

MANAGEMENT REQUIREMENTS

The Environmental Protection Agency's (EPA's) regulatory requirements for emergency planning, community right-to-know, and hazardous waste management may vary over time. Users are therefore advised to determine periodically whether new information is available.

* Emergency planning requirements

Employers owning or operating a facility at which there are 500 pounds or more of TEDP must comply with EPA's emergency planning requirements.

* Reportable quantity requirements (releases of hazardous substances)

A hazardous substance release is defined by EPA as any spilling, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment (including the abandonment or discarding of containers) of hazardous substances. In the event of a release that is above the reportable quantity for that chemical, employers are required by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) to notify the proper Federal, State, and local authorities.

The reportable quantity for TEDP is 100 pounds. If an amount equal to or greater than this quantity is released within a 24-hour period, CERCLA requires employers to notify the National Response Center IMMEDIATELY at (800) 424-8802 (in Washington, D.C. at (202) 426-2675), and 40 CFR Part 355.40 requires employers to notify (1) the State emergency response commission of any State likely to be affected by the release, and (2) the community emergency coordinator of the local emergency planning committee (or relevant local emergency response personnel) and to identify any area likely to be affected by the release.

* Community right-to-know requirements

Employers are not required by Section 313 of the Superfund Amendments and Reauthorization Act (SARA) to submit a Toxic Chemical Release Inventory form (Form R) to EPA reporting the amount of TEDP 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), EPA has specifically listed many chemical wastes as hazardous. TEDP is listed as a hazardous waste under RCRA and has been assigned EPA Hazardous Waste No. P109. This substance has been banned from land disposal and may be treated by fuel substitution or incineration. TEDP also may be disposed of in an organometallic or organic lab pack that meets the requirements of 40 CFR 264.316 or 265.316.

Providing more information about the removal and disposal of specific chemicals is beyond the scope of this guideline. EPA, U.S. Department of Transportation, 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 (202) 382-3000 (in Washington, D.C.) 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.

RESPIRATORY PROTECTION

* 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 TEDP 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 emergency situations. If the use of respirators is necessary, the only respirators permitted are those 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. Such a program must include respirator selection (see Table 1), an evaluation of the worker's ability to perform the work while wearing a respirator, the regular training of personnel, 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 NIOSH Respirator Decision Logic and the NIOSH Guide to Industrial Respiratory Protection.

Table 1 lists the respiratory protection that NIOSH recommends for workers exposed to TEDP. The recommended protection may vary over time because of changes in the exposure limit for TEDP or in respirator certification requirements. Users are therefore advised to determine periodically whether new information is available.

PERSONAL PROTECTIVE EQUIPMENT

Protective gloves and clothing should be worn to prevent any possibility of skin contact with TEDP. Chemical protective clothing should be selected on the basis of available performance data, manufacturers' recommendations, and evaluation of the clothing under actual conditions of use. No reports have been published on the resistance of various protective clothing materials to TEDP permeation; however, the following materials have been tested against chemically similar materials (organophosphorus compounds) and have shown resistance to permeation by these substances: a Viton/neoprene or butyl/neoprene mixture. Since specific test data are not available for TEDP, the information provided here should be considered as a guideline only. If permeability data are not readily available, protective clothing manufacturers should be requested to provide information on the best chemical protective clothing for workers to wear when they are exposed to TEDP.

If TEDP is dissolved in an organic solvent, the permeation properties of both the solvent and the mixture must be considered when selecting personal protective equipment and clothing.

Safety glasses, goggles, or faceshields should be worn during operations in which TEDP might contact the eyes (e.g., through splashes of solution). Eyewash fountains and emergency showers should be available within the immediate work area whenever the potential exists for eye or skin contact with TEDP.

REFERENCES

ACGIH [1986]. Documentation of the threshold limit values and biological exposure indices. 5th edition. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.

ACGIH [1991]. TLVs. Threshold limit values and biological exposure indices for 1991-1992. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.

[CFR]. Code of Federal regulations. Title 29 (Department of Labor), Parts 1910.134, 1910.1000, and 1910.1200. Washington, DC: U.S. Government Printing Office, Office of the Federal Register.

[CFR]. Code of Federal regulations. Title 40 (Protection of Environment). Washington, DC: U.S. Government Printing Office, Office of the Federal Register.

Hathaway GJ, Proctor NH, Hughes JP, and Fischman, ML [1991]. Proctor and Hughes' chemical hazards of the workplace. 3rd edition. New York, NY: Van Nostrand Reinhold.

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]. 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 [1988]. Testimony of the National Institute for Occupational Safety and Health on the Occupational Safety and Health Administration's proposed rule: 29 CFR 1910, Docket No. H-020, August 2, 1988. NIOSH policy 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.

NIOSH [1990]. 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. 85-114.

OSHA. OSHA Laboratory In-House Methods File. Salt Lake City, UT: U.S. Department of Labor, OSHA Analytical Laboratory.

RTECS [1992]. TEDP. Bethesda, MD: Registry of Toxic Effects of Chemical Substances, National Library of Medicine.

BIBLIOGRAPHY

ACGIH [1986]. Documentation of the threshold limit values and biological exposure indices. 5th edition. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.

[CFR]. Code of Federal regulations. Title 49 (Department of Transportation). Washington, D.C.: U.S. Government Printing Office, Office of the Federal Register.

DOT [1987]. 1987 Emergency response guidebook, guide 55. Washington, DC: U.S. Department of Transportation, Office of Hazardous Materials Transportation, Research and Special Programs Administration.

Farm Chemicals Handbook [1990]. Vol. 76. Willoughby, OH: Meister Publishing Co.

Hawley's condensed chemical dictionary [1987]. Sax NI, Lewis RJ. 11th edition. New York, NY: Van Nostrand Reinhold Company.

HSDB [1992]. TEDP. Bethesda, MD: The Hazardous Substances Data Bank, National Library of Medicine.

Merck Index [1983]. Windholz M. 10th edition. Rahway, NJ: Merck & Company.

Parmeggiani L [1983]. Encyclopedia of occupational health and safety. 3rd revised edition. Geneva, Switzerland: International Labour Organisation.

RTECS [1992]. TEDP. Bethesda, MD: Registry of Toxic Effects of Chemical Substances, National Library of Medicine.

Sax NI, Lewis RJ [1989]. Dangerous properties of industrial materials. 7th edition. New York, NY: Van Nostrand Reinhold Company.

Schwope AD, Costas PP, Jackson JO, Stull JO, Weitzman DJ [1987]. Guidelines for the selection of chemical protective clothing. 3rd edition. Cambridge, MA: Arthur D. Little Company. [Available from the American Conference of Governmental Industrial Hygienists, 6500 Glenway Avenue, Building 7, Cincinnati, OH 45211.]

Sittig M [1985]. Handbook of toxic and hazardous chemicals. 2nd edition. Park Ridge, NJ: Noyes Publications.

Condition	Minimum respiratory protection**
Airborne concentration of TEDP:
0.2 to 2 mg/m3 (10 × PEL)	Any supplied-air respirator equipped with a half mask and operated in a demand (negative-pressure) mode
0.2 to 5 mg/m3 (25 × PEL)	Any supplied-air respirator equipped with a hood or helmet and operated in a continuous-flow mode
0.2 to 10 mg/m3 (50 × PEL)	Any supplied-air respirator equipped with a full facepiece and operated in a demand (negative-pressure) mode, or Any supplied-air respirator equipped with a tight-fitting facepiece and operated in a continuous-flow mode, or Any self-contained respirator equipped with a full facepiece and operated in a demand (negative-pressure) mode
0.2 to 35 mg/m3 (175 × PEL)	Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode
Entry into IDLH(+) or unknown concentrations	Any self-contained respirator equipped with a full facepiece and operated in a pressure-demand or other positive-pressure mode, or Any supplied-air respirator equipped with a full facepiece and operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained breathing apparatus operated in a pressure-demand or other positive-pressure mode
Firefighting	Any self-contained respirator equipped with a full facepiece and operated in a pressure-demand or other positive-pressure mode
Escape	Any air-purifying, full-facepiece respirator equipped with a pesticide canister, or Any escape-type, self-contained breathing apparatus with a suitable service life (number of minutes required to escape the environment)

* The OSHA PEL is 0.2 mg/m³ as an 8-hour TWA. No NIOSH REL has been issued.
** Only NIOSH/MSHA-approved equipment should be used. Also note the following:

1. Respirators accepted for use at higher concentrations may be used at lower concentrations; respirators must not, however, be used at concentrations higher than those for which they are approved.

2. Air-purifying respirators are not listed due to the toxicity of TEDP.

(+) The TEDP concentration that is immediately dangerous to life or health (IDLH) is 35 mg/m³ [NIOSH 1990]. Use of chemical protective clothing may be necessary to prevent skin contact.