scope:

This publication is intended to provide useful information to producers, distributors, repackagers, and users of chlorine. It discusses nitrogen trichloride, a trace impurity commonly found in chlorine that could lead to the explosive decomposition of nitrogen trichloride in chlorine containing systems. There has been a history of such destructive decompositions that have resulted in deaths and injuries, equipment destruction, and chlorine releases.

The following topics pertaining to nitrogen trichloride are discussed:

• hazard awareness

• physical and chemical properties

• sources and mechanisms of formation

• control and monitoring

• prevention of formation

• methods for destruction

• limiting levels

• design/operating concerns

In concert with the initial edition of this pamphlet, the Institute's Properties, Analysis and Specifications Committee (PASC) developed a method for analysis of nitrogen trichloride in liquid chlorine which was subsequently issued by ASTM (9.2.1). The PASC believed at the time that there were suitable appropriate instruments commercially available to measure ammonia concentrations in brine (9.2.2). Additionally, CI Pamphlet 21 Nitrogen Trichloride - A Collection of Reports and Papers (9.1.1) is a compilation of reports and discussions on the subjects that have been presented at past Chlorine Institute Seminars or otherwise provided to the Institute.