The author sets forth a gas chromatographic technique for the detection of monochloracetic acid (MCAA) and its sodium salts in the air, in skin washings, overalls extracts, and urine. The substances were identified as propyl ether. The analysis was performed on a chromatograph supplied with a plasma-ionizing detector on a 2 m-long glass column, with the chromatrone N-AW-DMCS. The detection capacity in the sample was 0.005 microgram/microliter, in the air for MCAA - 0.5 mg/m3, for MCAA sodium salt - 0.25 mg/m3. Standard deviation did not exceed 0.16. The technique was tested in industrial conditions.