Abstract: A head protection or helmet suspension is shown having a ratchet adjustment apparatus for the adjustment of the suspension size where the ratchet apparatus is comprised of three parts, all pre-molded of resilient plastic material and having a pre-molded spring fixed around the center of the adjustment knob to engage pins in the ratchet case to lock the suspension size in position. The assembly has no metal parts and is therefore suitable for use around electricity and electrical apparatus.

Abstract: A hand-held air sampling pump can be operated with one hand to consistently sample an exact, predetermined volume of air by causing a bellows to compress and then elongate to form a vacuum inside of the bellows to draw an air sample through a detector tube and into the bellows.

Abstract: A catalytic gas detector circuit in which the temperature of a resistance gas sensing element, contained in a bridge circuit, is temporarily increased by energizing a current changing network for a finite period of time sufficiently long enough to burn impurities off of the surface of the sensing element.

Abstract: An exhalation valve decreases the exhalation pressure resistance through a valve by causing the moment of inertia of a flapper valve to be reduced along an axis by flattening out the curved edges of the umbrella-shaped flapper valve, thereby enabling greater ease in bending of the flapper valve.

Abstract: An apparatus for sensing the leakage of hydrocarbons from underground storage tanks having a hydrocarbon vapor sensor, a liquid sensor to determine the level of the groundwater and the positioning of the vapor sensor; and, alarm and trouble circuitry to indicate the presence of a hydrocarbon leak or a malfunctioning circuit. The apparatus also contains a timer mechanism to accurately determine whether or not the hydrocarbon has actually leaked from an underground storage tank or is present in the test area due to natural gases or above-ground spills.

Abstract: A chemical resistant garment material, that is a laminate formed from layers of skived Teflon that have been adhered to a cloth substrate, for use in protective clothing to guard against exposure to toxic agents.

Abstract: A foamaking generator for use on fires and hazardous material spill control, having a nozzle that may be adjusted to direct a foam concentrate stream to cover variable amounts of area of a screen so that low, medium and high expansion ratio foams can be produced using one foam generator.

Abstract: A material suitable for fabrication into protective garments that is a laminate formed from a layer of a reflective metallic material to provide flash protection and a layer that inhibits penetration by toxic and corrosive chemicals to protect against chemical exposure; both adhered to a cloth substrate to provide support.