A rapid procedure for the photometric determination of hydrazine in air at
a level of 0.05 mg/m(3) (0.5 MPC in workplace air) was developed. The proce
dure is based on the chromatomembrane absorption of hydrazine in a hydrochl
oric acid solution followed by reaction with p-dimethylaminobenzaldehyde. I
nterference from higher alcohols and aromatic amines was removed.