If engineering controls and work practices are not effective in controlling exposure to this material, then wear suitable personal protective equipment including approved respiratory protection. Have appropriate equipment available for use in emergencies such as spills or fire.

If respiratory protection is required, institute a complete respiratory protection program including selection, fit testing, training, maintenance and inspection. Refer to the CSA Standard Z94.4-93, "Selection, Use and Care of Respirators," available from the Canadian Standards Association, Rexdale, Ontario, M9W 1R3.

RESPIRATORY PROTECTION GUIDELINES:

NIOSH RECOMMENDATIONS FOR SULFUR DIOXIDE CONCENTRATIONS IN AIR:

UP TO 20 ppm: Chemical cartridge respirator with cartridge(s) to protect against sulfur dioxide*; or SAR*.

UP TO 50 ppm: Powered air-purifying respirator with cartridge(s) to protect against sulfur dioxide*; or SAR operated in a continuous-flow mode*.

UP TO 100 ppm: Full-facepiece chemical cartridge respirator with cartridge(s) to protect against sulfur dioxide; or gas mask with canister to protect against sulfur dioxide; or powered air- purifying respirator with a tight-fitting facepiece and cartridge(s) to protect against sulfur dioxide*; or full-facepiece SCBA; or full-facepiece SAR; or SAR with a tight-fitting facepiece operated in a continuous-flow mode*.

EMERGENCY OR PLANNED ENTRY INTO UNKNOWN CONCENTRATION OR IDLH CONDITIONS: Positive pressure, full-facepiece SCBA; or positive pressure, full-facepiece SAR with an auxiliary positive pressure SCBA.

ESCAPE: Gas mask with canister to protect against sulfur dioxide; or escape-type SCBA.

NOTE: The IDLH concentration for sulfur dioxide is 100 ppm.

NOTE: The purpose of establishing and IDLH value is to ensure that the worker can escape from a given contaminated environment in the event of failure of the most protective respiratory protection equipment. In the event of failure of respiratory protective equipment every effort should be made to exit immediately.

*NOTE: Substance reported to cause eye irritation or damage; may require eye protection.

ABBREVIATIONS: SAR = supplied-air respirator; SCBA = self- contained breathing apparatus; IDLH = immediately dangerous to life or health. The respirator use limitations specified by the approving agency and the manufacturer must be observed.

Recommendations apply only to NIOSH approved respirators.

Air-purifying respirators do not protect against oxygen-deficient atmospheres.

Chemical safety goggles. A face shield may also be necessary.

Acid resistant gloves, apron, slicker suit and boots, as required. Have a safety shower/eye-wash fountain readily available in the immediate work area.

Guidelines for sulfur dioxide:

RECOMMENDED (resistance to breakthrough longer than 8 hours): Saranex(TM), Barricade(TM), Responder(TM).

RECOMMENDED (resistance to breakthrough longer than 4 hours): Teflon(TM).

NOT RECOMMENDED for use (resistance to breakthrough less than 1 hour): polyethylene.

Recommendations are valid for permeation rates reaching 0.1 µg/cm²/min or 1 mg/m²/min and over. Resistance of specific materials can vary from product to product. Breakthrough times are obtained under conditions of continuous contact, generally at room temperature. Evaluate resistance under conditions of use and maintain clothing carefully.

Reference: Forsberg, K., et al. Quick selection guide to chemical protective clothing. 3rd edition. Van Nostrand Reinhold, 1997.

Remove contaminated clothing promptly. Keep contaminated clothing in closed containers. Discard or launder before rewearing. Inform laundry personnel of contaminant's hazards.