This report concerned the status of the Proficiency Analytical Testing (PAT) Program which is an effort of the American Industrial Hygiene Association and researchers at NIOSH and the Centers for Disease Control to maintain good analytical abilities at participating laboratories. Samples for analysis were mailed each quarter to participating laboratories. The laboratories were then evaluated on their findings to determine their proficiency. Laboratories must maintain an acceptable performance limit for each sample sent. Individual contaminants included metals, silica (14808607), asbestos (1332214), and organic solvents. A total of 1372 laboratories were enrolled in the PAT Program with 1306 laboratories submitting results on Round 112. PAT Round 113 was distributed on April 1, 1993, containing the following organic solvents: chloroform (67663), carbon-tetrachloride (56235), and 1,2- dichloroethane (107062). Metals in this round included cadmium (7440439), lead (7439921), and zinc (7440666). Silica had a calcite background and the asbestos was chrysotile (12001295).