TIME-WEIGHTED AVERAGE (TLV-TWA): Heavy work 0.05 ppm; Moderate work 0.08 ppm; Light work 0.1 ppm; For two hours or less exposure time, heavy/moderate/light work loads 0.2 ppm - Carcinogenicity Designation A4.

TLV BASIS - CRITICAL EFFECT(S) : Lung function; Irritation.

CARCINOGEN DESIGNATION A4 - Not Classifiable as a Human Carcinogen: Inadequate data on which to classify the substance as a human and/or animal carcinogen.

NOTE: In many Canadian jurisdictions, exposure limits are similar to the ACGIH TLVs. Since the manner in which exposure limits are established, interpreted, and implemented can vary, obtain detailed information from the appropriate government agency in each jurisdiction.

Ozone is not combustible (does not burn). However, pure ozone poses a serious fire and explosion risk by reacting with combustible materials, due to its very strong oxidizing ability.

Ozone decomposes slowly to oxygen with a half-life of 3 days at 20 deg C and of 3 months at -50 deg C. The rate of decomposition is increased by light, trace organic matter, nitrogen oxides, mercury vapour, peroxides, metals (e.g. copper, copper alloys, iron and chromium) and metal oxides.

Electrical sparks, heat, shock wave, intense light flash.

Reported values vary; 0.0076 ppm (minimum perceptible value); 0.005 -2.0 ppm (detection threshold); 0.1 ppm (recognition) .

NOT RELIABLE - variations in the detection range reported and olfactory fatigue occurs (ability to smell ozone is lost quickly as exposure continues).

This material is a VERY TOXIC, DANGEROUSLY REACTIVE, OXIDIZING gas. This material is manufactured on-site using an ozone generator. To prevent the release of gas into workplace air, it is produced, utilized and any excess destroyed within a totally enclosed system. It is extremely important that all engineering controls are operating. People working with this chemical should be properly trained regarding its hazards and its safe use. Only authorized personnel should have access to the work area. All the ozone generator supplier's guidelines regarding operating procedures, maintenance, safety precautions (e.g. lock-out) should be followed closely.

If ozone is released, immediately put on a suitable respirator and evacuate the area. In case of leaks, escape-type respiratory protective equipment should be readily available in the immediate work area. Immediately report leaks and ventilation or system failures. Precautions such as regular visual checks made by another person or a telephone call-in procedure should be taken to ensure the continued safety of lone workers or workers in remote locations.

Be aware of typical signs and symptoms of poisoning and first aid procedures. Any signs of illness should be reported immediately to supervisory personnel. Absolutely no contact with incompatible materials. For example, everything which comes in contact with ozone must be maintained free of oil and grease.

Keep work area clear of all materials which can burn. Do not perform any welding, cutting, soldering, drilling or other work on an empty vessel or piping until it has been thoroughly purged and all traces of ozone have been removed. A permit (lock-out) system should be implemented for all maintenance activities in the work area. The ozone handling system should be checked for leaks after maintenance work. Have suitable emergency equipment for fires and leaks readily available. Practice good housekeeping. Maintain handling equipment. Comply with applicable regulations.

Engineering methods to control hazardous conditions are preferred. Methods include mechanical ventilation (local exhaust), process or personnel enclosure, control of process conditions, and process modification (e.g. substitution of a less hazardous material). Because of the high potential hazard associated with this substance, stringent control measures are required. A fully enclosed system is required. Administrative controls and personal protective equipment may also be required.

The ozone generator and associated equipment should be housed in a separate room, preferably in a separate building. The room/building should have an identifying sign and only authorized personnel should have access. The ozone room/building should have a separate ventilation system equipped with a cleaning device so as to destroy the ozone before it is discharged to the atmosphere. An air monitoring system should activate an alarm and the ventilation system in the event of a leak. A power supply switch for the ozone generator should be provided in a safe and readily accessible location, away from the ozone room/building.

Gaskets, piping and sealing compounds must be made of compatible materials. Pipes should be kept as short as possible and mechanically supported. Piping should be protected from shock or vibration and able to withstand the system pressure.