Ozone is a toxic gas. Some installations require proper safety signage and training of staff. Caution should always be exercised when working with ozone. Consult the manufacturer or authority having jurisdiction for recommendations and the requirements for a particular installation if in doubt. In general, the concentrations used for most applications combined with the easily detectable nature of the gas make ozone an extremely safe oxidant to use.

The American Conference of Governmental Industrial Hygienists (ACGIH) recommended exposure limits for ozone are as follows:

Time-Weighted Average (TLV-TWA)

Notice of Intended Change
The addition of the Carcinogenicity Designation A4 - Not Classifiable as a Human Carcinogen as well as a TLV-TWA of 0.2 ppm for light, moderate or heavy workloads of 2 hours or less has been proposed.

Note: In many Canadian jurisdictions, exposure limits are similiar to the ACGIH TLV's. 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.

TLV Basis-Critical Effects

Pulmonary function (lung function), Irritation, Headache.

Odour Threshold

Ozone has a very low odour threshold. Reported values vary; .0076 ppm (minimum perceptible value); 0.005 - 0.02 ppm (detection threshold); 0.1 ppm (recognition).

MSDS