Abstract:
Testing apparatus is provided in the form of a pen and has a body (11) and cap (12). The body (11) has an inlet (13) at its tip which communicates with a fuel cell chamber (14), containing a fuel cell (15), and, via that chamber, with a passage (16) and a cylinder (17). A piston (18) is mounted in the cylinder (17) for operation by a button (19), a spring (21) and latch (22) such that it can draw air through the inlet (13) to the fuel cell (15). If the inlet (13) is placed in a user's mouth the apparatus can provide an indication of his breath alcohol concentration, for example, on display (23).
Abstract:
This invention relates to a method and apparatus for measuring ethanol vapour concentration. Both methods and the apparatus determine the gradient of the initial steady state part of the output of a fuel cell prior to a peak height being reached and use that determination to generate an ethanol vapour concentration signal.
Abstract:
This invention relates to devices for providing vapour samples of volatile components of a solution and apparatus for allowing such samples to be tested. Two different sample containers (10 and 52) are described. In each, a volatile solution is retained so that the volatile component equilibrates with a headspace from whence it can be drawn off into testing apparatus. In the device (10), the volatile component is retained by a gas-permeable-hydrophobic membrane (14), whilst in the device (52) the solution is retained in absorbent material (56). The device (10) has associated apparatus (26), whilst the device (52) is complete in itself. In each case, when the testing apparatus is located on a sampling outlet port, it causes a valve to open allowing sampling to occur.
Abstract:
A fuel cell sensor (10) comprises a main body (11) in which are mounted working electrodes (12), counter electrodes (13) and respective contacts (14 to 17). The working electrodes (12) are mounted facing each other to define a sample space between them. The electrodes (12) are electrically interconnected in parallel as are the two counter electrodes (13). This arrangement makes it possible to provide a very large working electrode surface area for a small volume sample space (22).
Abstract:
A mouthpiece for apparatus for detecting the presence of alcohol or drugs in the breath of a user is generally indicated at (10) and comprises a body (11) and filter insert (12). The body (11) includes a tube (13) and an open end (14) and a closed end (15) in which the breath inlet (16) is offset from the access of the tube (13). The filter insert (12) includes a perforate plate (21) which extends across the breath path to trap the majority of saliva or other contaminates. The size and number of the perforations (24) in the plate are selected so as to provide an overall cross-section which is equal to or greater than the smallest cross-section of the inlet (16).
Abstract:
This invention consists in breath testing apparatus (10) comprising a breath tube (11), a fuel cell housing (12) incorporating a pump system (12a), a fuel cell (13), a control and computational unit (14) and display (15). A thermistor (22) is provided to detect the temperature of the housing (12) during measurement and the unit (14) compensates the fuel cell output in accordance with the detected temperature.
Abstract:
This invention relates to apparatus for taking a fluid sample; for example apparatus for taking a breath sample for use in a breath alcohol tester. The apparatus (10) has a breath tube (11) from which a sample can be taken by a latch-operated sampling mechanism (13). The mechanism is released for sampling by the downward movement of a projection (30). Prior to this downward movement the projection (30) is lifted by an expansible bag (22) being inflated by the subject's breath. When the subject stops exhaling, or even reverses their breath, the bag (22) deflates by venting through orifice (22a) under the weight of the lever arm (25) and the force of the spring (29). This deflation results in the downward, and activating, movement, mentioned above of the projection (30).
Abstract:
PCT No. PCT/GB94/01489 Sec. 371 Date Jan. 16, 1996 Sec. 102(e) Date Jan. 16, 1996 PCT Filed Jul. 8, 1994 PCT Pub. No. WO95/02817 PCT Pub. Date Jan. 26, 1995A fuel cell sensor (10) comprises a main body (11) in which are mounted working electrodes (12), counter electrodes (13) and respective contacts (14 to 17). The working electrodes (12) are mounted facing each other to define a sample space between them. The electrodes (12) are electrically interconnected in parallel as are the two counter electrodes (13). This arrangement makes it possible to provide a very large working electrode surface area for a small volume sample space (22).
Abstract:
PCT No. PCT/GB96/03064 Sec. 371 Date Sep. 17, 1998 Sec. 102(e) Date Sep. 17, 1998 PCT Filed Dec. 12, 1996 PCT Pub. No. WO97/21999 PCT Pub. Date Jun. 19, 1997A method and apparatus for measuring ethanol vapor concentration wherein a cell output is plotted with respect to time. The gradient of the steady rate portion of the plot is determined and an ethanol vapor concentration signal is generated from the determined gradient.