Abstract: An analyte sensing probe for attachment to a ferromagnetic surface, the probe comprising a flexible collector plate for placing against the surface, the collector plate having a hole in communication with one end of a capillary and defining when placed against the surface a gap through which air may flow from the periphery of the plate to the capillary, the air entraining any analyte passing through the surface for measurement by an instrument connected in use to the capillary, wherein, in order to cause the collector plate to conform to the surface, the probe further comprises a flexible magnetic assembly positioned on the side of the collector plate remote from the surface, the assembly being composed of a plurality of mutually articulated segments of which at least some are magnetically attracted to the surface.

Abstract: An analyte sensing probe for attachment to a ferromagnetic surface, the probe comprising a flexible collector plate for placing against the surface, the collector plate having a hole in communication with one end of a capillary and defining when placed against the surface a gap through which air may flow from the periphery of the plate to the capillary, the air entraining any analyte passing through the surface for measurement by an instrument connected in use to the capillary, wherein, in order to cause the collector plate to conform to the surface, the probe further comprises a flexible magnetic assembly positioned on the side of the collector plate remote from the surface, the assembly being composed of a plurality of mutually articulated segments of which at least some are magnetically attracted to the surface.

Abstract: A gas-equilibrated, volatile-in-water detector comprises a gas-sensing chamber having an orifice closed by a hydrophobic, vapour-porous membrane, typically PTFE, sealed to the periphery of the orifice. Membrane is also sealed to an external wall of a surrounding enclosure and forms an entry point to a second gaseous enclosure external of the gas-sensing chamber. A PID or similar sensor generates a measurable current or voltage in response to the partial pressure of the analyte within the gas-sensing chamber without the sensor significantly altering such equilibrium partial pressure.