Testing the Natural Gas Detection System Sensor
Daimler Truck strongly recommends that all operators follow California Code of Regulations (CCR) inspection requirements, regardless of where the vehicle is operated. Per Title 13 CCR § 935 (2), gas detection systems should be tested three times per year at equal intervals. The testing procedure should simulate the same operating environment in which the vehicle is used. Test results validating the performance of the gas detection system within the parameters established by the component manufacturer and NFPA 52 should be maintained as a permanent part of the vehicle service records. Use of alcohol, propane, and other harsh liquids or gases are not acceptable methods of testing.
Test the sensors three times per year, after any system component has been replaced, or if the vehicles was involved in an accident or fire. The gas detection system sensors must be tested regularly by a trained technician using certified test equipment that satisfies CCR § 935 (2) or NFPA 52 regulations.
Daimler Truck recommends the highest level of safety validation if there are multiple validation requirements in the state or locally where the vehicle is operated or parked.
- Press and hold the Push To Test button for one minute. The system will proceed with a self-diagnostic test that will include illumination of the Trace and Significant gas concentration lights, and the sensor fault lights.
- Verify the large red light and buzzer activate, and that all lights illuminate or flash to ensure that all bulbs are operational.
- Sensor Test: The gas detection system sensors must be tested
using qualified test gas, which can be purchased as part of a test
kit. Testing with alcohol or heavy gases such as butane or propane
does not satisfy CCR § 935 (2) or NFPA 52 regulations. Expose
each sensor to qualified test gas for at least 30 seconds. The system
will proceed through the alarm procedure consistent with a significant
leak and the buzzer will sound after approximately 15 seconds. If
a sensor fails to respond after exposure to the test gas, replace
the sensor.
Table 1, Control Module Functions
Control Module Functions
Item
Display
Function
Action Required
Green Power Light
Illuminated
System is on.
None required.
Unlit
Detection system is not functioning.
Ensure the batteries are connected and replace any blown fuses. If the gas detection system is still not functioning, replace the system immediately.
SIGNIFICANT Gas Concentration Lights
Red (illuminated)
Dangerous gas concentration detected.
Suspend vehicle operation immediately and follow alarm procedures.
Table 1, Control Module Functions