Standards and procedures for the operation, adjustment, calibration and certification of the Division-approved smoke opacity meters, chassis dynamometers, and other required equipment in the performance of diesel opacity inspections for the Diesel Opacity Inspection Program.
Diesel opacity inspection required by the Diesel Opacity Inspection Program shall not be performed unless the equipment used meets the specifications of the Colorado Diesel Opacity Inspection Program as defined in this regulation and as approved by the Division. Opacity meters, chassis dynamometers, photo tachometers and strip chart recorders must be approved by the Division. A manufacturer requesting the approval of an instrument for use in Colorado's Diesel Opacity Inspection Program shall make application thereof on forms provided thereby, and sources of vendors for the qualifying instruments may be obtained from the Program Administrator, Mobile Sources Section, Air Pollution Control Division, Colorado Department of Public Health and Environment, 4300 South Cherry Creek Drive, Denver, CO, 80246.
Any changes to design or performance characteristics of components' specifications which may affect equipment or instrument performance must be approved by the Commission. It will be the instrument manufacturer's responsibility to confirm that such changes have no detrimental effect on opacity meter or other equipment or instrument performance. All equipment and instruments used in Colorado's Diesel Opacity Inspection Program will be updated as needed and specified in revisions to Commission Regulation Number 12.
Every licensed station shall have on the premises an approved portable opacity meter meeting specifications to conduct opacity tests for the Diesel Opacity Inspection Program. Only opacity meters approved by the Division shall be used for opacity inspections in the Diesel Opacity Inspection program.
The opacity meter is to be portable in design and function with an emphasis on compactness and light weight. The instrument will consist of two major, separate components connected by an interconnecting cable. The major components are the stack monitor/sensor and the control/indicator unit.
Every heavy-duty diesel vehicle inspection station shall have a photo tachometer capable of sensing a vehicle's engine rpm and digitally displaying that rpm in the vehicle operator's compartment. This tachometer must be capable of measuring rpm from 0-6000 rpm with an accuracy of plus or minus five rpm or better. For heavy-duty on-road testing stations this unit must be of portable design with the readout capable of being read from the vehicle's cab, and must be easily interfaced with the strip chart recorder.
In those instances where on-road opacity testing will be utilized, stripchart recorders/digital recording devices shall be used in order to accurately monitor and analyze the test sequence.
Description of an approved stripchart recorder/digital recording device is as follows:
Two neutral density filters, certified and calibrated by the Division, must be kept by each diesel testing station for weekly calibration checks of the opacity meter. The results of the calibration checks of each approved opacity meter must be entered into the inspection software provided by the Division and made available to Department of Revenue Air Environmental Systems Technicians upon request during station inspections.
For use in the Diesel Opacity Inspection Program, the thermometer must be a laboratory grade ambient temperature measuring device with a range of at least 20°F (twenty degrees) through 120°F (one-hundred-twenty degrees) and an attested accuracy of at least plus or minus 1° (one degree) Fahrenheit with increments of one degree, with protective shielding, and approved by the Department of Revenue.
Adequate safety restraint equipment for all dynamometer test stations is required. Restraint equipment must be capable of restraining the type of vehicles tested at that station. Equipment may be chains, fabric tie-down straps, wheel chocks, as appropriate and as approved upon licensing.
Light-duty inspection stations are required to have available on premises and for use during opacity inspections, an auxiliary engine cooling fan which meets the following minimum specifications:
Guarded fan complying with OSHA regulations.
CFM free air delivery of 3200 CFM
Fan diameter of 24 inches.
1/4 H.P. motor.
If a closed exhaust system is utilized, the pressure within the system shall be maintained between 4 inches H2O positive pressure and 2 inches H2O negative pressure at all times when any given vehicle is undergoing opacity testing.
5 CCR 1001-15-B-II