Improvements in or relating to testing apparatus for detectors or indicators of inflammable vapours or gases

摘要

PICT:0686091/III/1 In apparatus of the diffusion type for the detection or indication of inflammable gases or vapours, a device for ascertaining at what concentration of gas the apparatus is set to operate comprises a stand 1 on the vertical wall 2 of which is mounted a bracket 3 provided with electrical contacts 4 for the filament and warning lamp circuit of the detector apparatus and to which bracket the plate of the detector carrying the filament, porous vessel, diaphragm and warning lamp, is secured, a vacuum gauge 6 also being mounted on the vertical wall and adapted to be connected by means of a flexible tube 7 to the porous vessel. The gauge 6 is provided with a scale giving gas percentages calibrated in accordance with the vacuum reading of the gauge.