Carbon Monoxide Headquarters

CO & Motor Vehicles

Proposed Solution

System Characteristics:

  • Equip motor vehicles with a sensor array in the auto compartment that is sensitive to:
    - Carbon monoxide
    - Carbon dioxide
    - Oxygen

  • Sensor output is directed to a microchip with embedded program such that:
    - Measured CO conc. is integrated over time in a manner modeling human CO uptake, and thus provides a Low warning alarm at 35 ppm (7% COHb), and a High warning alarm at 100 ppm (14% COHb).
    - A CO conc. at 100 ppm and above, as well as rapidly rising CO2 conc. and rapidly falling O2 conc., immediately trigger engine shut-down.

    Advantages of Scheme:

  • Low and high alarms give warning of CO presence at levels shown to impair psychometric performance ("drowse alarm") and known to produce health damage in at-risk groups (CHF, CAD, fetus). These would give warning of elevated ambient CO and/or abnormal exhaust gas leaks into the motor vehicle driver/passenger compartment.
  • With conc. x time computer integration, neither heavy cigarette smoking, auto tunnels, nor congested roads would be likely to trigger even the low CO alarm.
  • Use of CO2 conc. and O2 conc. changes along with CO conc. will prevent "false positives", ie. inappropriate engine shut-down. Changes in the concentrations of these three gases will provide a unique "signature" of the suicide attempt.


  • A second sensor array might be placed outside the motor vehicle, preferrably near the rear tailpipe. This would cause engine shut-down in those instances where people attempt to commit suicide out of the car, behind the tailpipe (in garage, outside, etc.).
  • If the cost of the 3-sensor array proves too great, only one sensor responding to CO may be used. In this event, threshold CO conc. might be set somewhat higher in order to avoid inappropriate engine shut-downs.


    CO detectors are standard equipment in households in the USA, warning of furnace, etc. malfunction. They are also becoming common in motor homes and on pleasure boats. Why shouldn't such devices now become standard equipment in motor vehicles, considering that they are such prodigious generators of CO in such close proximity to the driver and passengers.

    Photo above, right (R->L): Pierre Baume, Dr. Michaela Skopek & Kirsten Cross (Youth Health Advocate, AMA).

    ...... last changed 02/12/00

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