Abstract: A method of testing air for measuring the chromate and chromic acid aerosols therein, comprises, passing the air through a testing tube after each end of the tube has been broken to cause the particles in the air to become entrained on a filter in the tube and, thereafter, breaking an ampoule of sulfuric acid in the tube so that it flows through the filter and dissolves the entrained particles and brings them into contact with a filling material which is also arranged in the tube and which produces a reaction with the particles of chromate and chromic acid which are deposited on the filter. The reaction produces a violet dye, the intensity of the discoloration being directly proportional to the mass of the deposited chromate or chromic acid.

Abstract: A device for testing the tightness of fit of a gas mask which has a tubular respiratory air inlet and a tubular exhaling air outlet, which is applied over the face of a wearer, comprises a bag-like headpiece which is engageable over the wearer's head and is preferably made of a transparent material, such as plastic, and which is provided with an opening for the wearer's neck and an opening for the tubular air inlet of the gas mask with a resilient rim for tightly engaging these parts when the headpiece is positioned on the wearer's head. The headpiece also includes a tubular exhaling air connection piece which is formed on the interior of the headpiece in a position to be engaged over the tubular exhaling air outlet of the gas mask. The connection piece includes an uptake passage for the passage of air directly from the mask outwardly through the passage.