WAC 296-307-40039. Electrical equipment and wiring

(1) Electrical equipment and wiring for use in ammonia installations must be general purpose or weather resistant as appropriate. (2) Where concentrations of ammonia in the air in excess of 16% by volume are likely to be encountered, electrical equipment and wiring must be specified by and installed according to chapter 296-307 WAC Part T, for Class I, Group D locations.