Abstract: A bubbler bottle has an upper chamber and a lower chamber of smaller diameter than the upper chamber. A central inlet tube extends from near the bottom of the lower chamber up through the upper chamber and the top of the bottle. An exhaust tube extends from near one side of the inlet tube laterally out through the side of the upper chamber, with its outer end adapted to be connected to a suction pump for drawing contaminated air down through the inlet tube and out of its lower end into a predetermined volume of liquid in the lower chamber. The liquid is spaced from a collar which encircles the inlet tube and is sealed to the side of the upper chamber below the exhaust tube but with clearance around the inlet tube. The capacity of the lower chamber is such that the liquid remaining in it when the bottle is on its side is beneath the inlet tube, and the capacity of the upper chamber is such that when the bottle is inverted all of the liquid in the inverted upper chamber will be below the exhaust tube.

Abstract: A gas sampler in the form of a bubbler is associated with a transparent detector tube containing a chemical that changes color when a toxic gas flows through it. Conduit means connect the air outlets of the two devices with the inlet of a suction pump to draw air through the bubbler and tube simultaneously. The flow of air from the bubbler to the pump is restricted relative to the flow from the tube to the pump.

Abstract: A shallow cup has a central inlet opening in its base and a filter disc closing its open end, whereby a hollow capsule is formed. A barrier member inside the cup is located between its base and the filter and has a central portion spaced from the filter and the cup inlet. This central portion is provided with holes around a solid central area that has a diameter at least as great as the inlet opening. A separable two-part cassette contains the capsule with its marginal area clamped between the two parts. The part containing the cup is provided with a central inlet port in an end wall spaced from the capsule, and the other part of the cassette covers the filter and is provided with an outlet port. Between the capsule and inlet port in the cassette there is a baffle that causes nonrespirable particles in the incoming air to be trapped before they can reach the capsule.