Not applicable

(For Structure, see paper copy)

Finely divided wood particles, powdered wood, sawdust, wood flour, softwood dust, wood dust

1. CAS No.: Data not available

2. RTECS No.: ZC9850000

3. Specific DOT number: None

4. Specific DOT label: None

Western red cedar dust is any wood particle arising from the processing or handling of western red cedar. This wood has a very characteristic cedar smell.

1. Molecular weight: Not applicable.

2. Boiling point: Not applicable.

3. Specific gravity: Not applicable.

4. Vapor density: Not applicable.

5. Melting point: Not applicable.

6. Vapor pressure: Not applicable.

7. Solubility: Not applicable.

8. Evaporation rate: Not applicable.

1. Conditions contributing to instability: None reported.

2. Incompatibilities: None reported.

3. Hazardous decomposition products: None reported.

4. Special precautions: A severe explosion hazard may exist if a wood dust cloud comes into contact with a source of ignition. Partially burned or scorched wood dust is especially hazardous if it is dispersed in air because of its explosivity.

The National Fire Protection Association has not assigned a flammability rating to western red cedar dust. Other sources rate western red cedar dust as a combustible solid when this substance is exposed to heat or open flame.

1. Flash point: Not applicable.

2. Autoignition temperature: Data not available.

3. Flammable limits in air: Data not available.

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

Fires involving western red cedar dust should be fought upwind from the maximum distance possible. Isolate the hazard area and deny access to unnecessary personnel. Firefighters should wear a full set of protective clothing and self-contained breathing apparatus when fighting fires involving western red cedar dust.

The Occupational Safety and Health Administration (OSHA) has established a permissible exposure limit (PEL) of 15 milligrams per cubic meter (mg/m(3)) for the total dust and 5 mg/m(3) for the respirable fraction of western red cedar dust (as a nuisance dust).

The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limit (REL) for western red cedar dust of 1 mg/m(3) of air, as a TWA for up to a 10-hour workday and a 40-hour workweek [NIOSH 1992].

The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned western red cedar dust (as a soft wood) a threshold limit value (TLV) of 5 mg/m(3) as a TWA for a normal 8-hour workday and a 40-hour workweek and a short-term exposure limit (STEL) of 10 mg/m(3) for periods not to exceed 15 minutes. Exposures at the STEL concentration should not be repeated more than four times a day and should be separated by intervals of at least 60 minutes [ACGIH 1994, p. 36].

The NIOSH limit is based on the risk of pulmonary dysfunction and other respiratory effects [NIOSH 1992].

The ACGIH limits are based on the apparent low risk of upper respiratory tract effects [ACGIH 1991, p. 1729].

Exposure to western red cedar dust can occur through inhalation, ingestion, and eye or skin contact.

1. Effects on Animals: No information was available on the health effects of western red cedar dust on experimental animals.

2. Effects on Humans: Exposure to western red cedar dust can result in the development of rhinitis, dermatitis, and asthma [ACGIH 1991]. Although wood dusts have long been associated with nasal cancer and pulmonary dysfunction, no reports in the available literature specifically describe these conditions in relation to exposure to western red cedar dust. It is believed that the nasal cancer and more severe respiratory effects are associated with exposure to dusts from the hardwoods such as beech, walnut, and oak [ACGIH 1991].

1. Acute exposure: Acute exposure to western red cedar dust may result in irritation of the eyes, skin, or respiratory tract.

2. Chronic exposure: Chronic exposure to western red cedar dust may result in dermatitis, asthma, or respiratory system congestion.

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.

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.

Before a worker is placed in a job with a potential for exposure to western red cedar dust, 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 skin and respiratory system [NIOSH 1994a]. 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 western red cedar dust 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 skin or respiratory system [NIOSH 1994a].

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 western red cedar dust exposure. The interviews, examinations, and medical screening tests should focus on identifying the adverse effects of western red cedar dust on the skin or respiratory system [NIOSH 1994a]. Current health status should be compared with the baseline health status of the individual worker or with expected values for a suitable reference population.

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 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 western red cedar dust.

Western red cedar dust is not subject to EPA emergency planning requirements under the Superfund Amendments and Reauthorization Act (SARA) (Title III) in 42 USC 11022.

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 western red cedar dust; there is no reportable quantity for this substance.

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 western red cedar dust emitted or released from their facility annually.

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 western red cedar dust 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.

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 western red cedar dust 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).

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].