RCRA Exclusions

Toxic gases causing worker health and safety problems

Discharges that result in toxic gases, vapors, or fumes, in a quantity that may cause acute POTW worker health or safety problems, are also prohibited ( 40 CFR §403.5(b)(7): see 55 FR 30129 ). For example, traces of cyanide let down the drain may react with acidic wastewater to generate poisonous hydrogen cyanide gas. Although the regulatory prohibition applies to exposure of POTW workers, laboratory personnel should take precautions to eliminate the chance of toxic gases entering the laboratory through sink drains (i.e., adjacent laboratories should not simultaneously release acidic wastes and cyanide or sulfide bearing wastes).