Abstract: A colorimetric gas diffusion testing tube is disclosed that is to be opened at one end and that contains a granular indicator layer. The testing tube detects a gas that does not directly change the color of the indicator layer. When the tube is viewed from the end which is to be opened, the indicator layer that is adjacent the opening end is inert to the gas that is to be detected. The indicator layer is followed by a porous reagent layer for converting this gas into the substances that change the color of the indicator layer.

Abstract: A wearable, air-sampling device includes a head frame comparable to an eyeglass head frame which has a forehead engaging cross piece and an ear-engaging piece on each side extending rearwardly from the forehead engaging portion which are adapted to engage over respective ears of the wearer and which includes a detachable gas-tester holder mounted on the frame at some visible location, for example, between the eye portions of the forehead piece or over each eye of even on a temple piece.

Abstract: A colorimetric gas dosimeter, which contains a granular indicator substance in a closed, transparent, hollow unit that can be opened on one side, is provided in such a way that the diffusion cross section for the hazardous substance molecules is independent of the degree of discoloration of the indicator substance and the detection sensitivity is thereby increased. This is achieved by sub-dividing the hollow unit into several chambers extending along its longitudinal axis, at least one of which is filled with the granular indicator, and is located adjacent to an indicator free chamber and is separated from this by a separating wall permeable to gas.

Abstract: A diffusion sample collector for gaseous media, consisting of a transparent container open at both ends, which contains a collecting layer and has at its two open ends permeable retaining elements. The collector is improved in such a manner that the presence of hazardous substances in the surrounding air to be analyzed can be recognized during the collecting of the samples in order that an unnecessary analysis of the collecting layer can be prevented in the absence of hazardous substances and also gas eruptions can be noticed immediately. For this latter purpose, an additional layer is provided in the container, which is separated from the collecting layer by a dividing wall and is in contact with the gas to be analyzed through the opposite end and its retaining element.

Abstract: A housing contains a diffusion indicator tube provided with a predetermined breaking point and the housing has an upper part and a lower part joined together by a film hinge. To open the inserted diffusion indicator tube its predetermined breaking point is positioned opposite the film hinge. By bending the housing parts, the break-off end breaks off the test tube at the predetermined breaking point, thereby opening the reaction section. The parts of the test tube are removed, and then the reaction section is pushed into the upper part, now with its closed end first, whereupon it is snapped into the lower part. Its opening at the bottom shoulder of the lower part is exposed to the ambient atmosphere which diffuses into it. In the presence of the gas to be monitored there will be discoloration due to reaction. The discoloration can be observed continuously through the open side of the holding means.

Abstract: A method of measuring gas, vapor and aerosol components in an air sample, using a gas detecting device, includes a glass tube having openable ends for the flow of test gas therethrough and a filter therein entraining components to be measured, comprises, breaking an ampoule of a liquid solvent for the materials entrained by the filter to cause the solvent to pass through the filter into a granular reaction layer and then through an empty chamber. The testing tube includes a liquid lock which is formed by a hydrophobic paper which is disposed downstream of the empty chamber so as to retain the reacting products in the chamber so they may be viewed. The reactant products undergo a color change in proportion to a substance to be detected, such as sulfuric acid, for example.