§ 18-28-510.2 — Where required

18-28-510.2 Where required.

A hazardous exhaust system shall be required wherever operations involving the handling or processing of hazardous materials, in the absence of such exhaust systems and under normal operating conditions, have the potential to create one of the following conditions: 1. A flammable vapor, gas, fume, mist or dust is present in concentrations exceeding 25 percent of the lower flammability limit of the substance for the expected room temperature. 2. A vapor, gas, fume, mist or dust with a health-hazard rating of 4 is present in any concentration. 3. A vapor, gas, fume, mist or dust with a health-hazard rating of 1 , 2 or 3 is present in concentrations exceeding 1 percent of the median lethal concentration of the substance for acute inhalation toxicity.