A field evaluation of air sampling methods for TNT and RDX

A comparative field study was conducted at an ammunition plant to evaluate the use of several sampling techniques for 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). The objective was to compare the currently recommended combination Tenax-plus-filter tubes with the older, colorimetric diethylaminoethanol bubbler method which was in use in July 1950 when the American Conference of Governmental Industrial Hygienists (ACGIH) published their first Threshold Limit Values (TLVs). These values included a TLV of 1.5 mg/m3 for TNT. Regular Tenax tubes and 37-mm glass fiber filters also were tested since they also had been used by the United States Army for a number of years. The survey results showed fair agreement between the bubbler and tube methods in those instances where sufficient TNT was present to produce a measurable color in the diethylaminoethanol (DEAE). The glass fiber filters were not satisfactory for TNT retention, but the two types of tubes both were effective. The combination tubes were superior for RDX and appeared to be the best overall sampling medium.