Legal basis and policy intent
- The circular is issued pursuant to Section 34(1) of R.A. 4136 and Presidential Decree No. 1181.
- The stated objective is to abate excessive smoke emission from diesel fed motor vehicles.
- The stated purpose is to promote public health and environmental safety.
- The testing rules are directed to ensure diesel vehicles comply with prescribed smoke emission standards.
Scope and who must be tested
- All diesel powered motor vehicles must undergo smoke and exhaust emission tests prior to registration in Metro Manila.
- Tests before registration must be conducted in the district office and MVIS.
- For-Hire vehicles must be subjected to the same pre-registration smoke testing in the district office and MVIS.
- Already registered vehicles that are found emitting excessive smoke while operating in any public highway must be subjected to the same test.
- The circular requires that the post-registration tests on public highways be conducted by properly equipped law enforcement units.
Smoke emission standard (limits)
- Smoke opacity must not exceed prescribed limits based on the testing meter used.
- The black soot content must not exceed 2.5 m-1 light absorption coefficient or 48% in the Iyasaka bosch opacity-type meter.
- The black soot content must not exceed 66% in the Hartridge smoke emission unit (hsu).
- The circular also recognizes compliance using any equivalent smoke emission tester subject to the stated meter-based limits.
Test procedure requirements (free acceleration)
- Operators must observe the free acceleration feet procedure strictly.
- The test must be performed with the motor vehicle in a condition that supports valid measurement:
- The engine fast is to be carried out on a stationary vehicle at normal engine operating procedure with the combustion chamber not cooled or fouled by prolonged idling preceding the test.
- The exhaust system must have no hole through which gases emitted by the engine may escape or be diluted.
- The test must control vehicle and control settings:
- Place the vehicle gear in neutral and engage the hand brake effectively.
- Start the engine and warm up to normal operating temperature.
- The procedure for opacity measurement must follow the tester system setup and measurement steps:
- Insert the sampling probe at the tollpipe.
- Ensure the tester is correctly plugged to the computer and the application program is running and ready for data entry.
- Accelerate the engine two to three times to remove soot deposits and other carbon particles.
- The required acceleration pattern and stabilization rule must be followed:
- Depress the accelerator quickly not violently to obtain maximum fuel delivery from the injection pump.
- Maintain until maximum speed is reached for about three (3) seconds and the governor comes into action.
- Release the accelerator until the engine reaches idling speed.
- Repeat the free acceleration procedure three times until the maximum opacity values register in consecutive free acceleration tests and are stabilized.
- Values are treated as stabilized when three (3) consecutive readings are within a band width of 0.3 m-1 (equivalent to percentage in the bosch-opacity meter or 5 hsu in the Hartridge meter) and do not form a decreasing sequence.
- The test result must be the arithmetic mean of the three stabilized values automatically given in the computer monitor read out, hard copy print out, or tester display.
- For vehicles with two or more exhaust pipes, the opacity must be measured for all exhaust pipes, and the reading of the highest opacity must be recorded.
- After the test, the operator must seal the full-load screw of the injection pump/delivery system.
Forms, documentation, and record handling
- The circular requires use of the computer generated form.
- If there is a power outage or the computer is not linked or operational with the tester, personnel must use the same format for manual generation and later encode it in the computer.
- All test data related to the vehicle and testing must be encoded in a data diskette for uploading to regional and central office computers.
- A copy of the test result print out must be attached to the MVIR.
- A copy of the test result print out must also be given to the vehicle owner.
Test schedule and validity period
- Smoke emission tests may be conducted within a month prior to registration.
- Tests conducted within that window remain valid for 30 days from the date of the tests for purposes of complying with the registration requirement.
Fees for smoke emission testing
- The circular sets a schedule of fees payable for each motor vehicle smoke emission test.
- For motor vehicles under L, M, H, UV & TX denominations, the fee is FIFTY PESOS (P50.00).
- For motor vehicles under T or TB denominations, the fee is SEVENTY FIVE PESOS (P75.00).
- For every vehicle tested in the owner’s garage, an additional fee of FIFTY PESOS (P50.00) must be collected in addition to the fee prescribed above.
Supersession and effect
- All circulars, orders, memoranda, and instructions contrary to these rules are superseded and amended accordingly.
- The circular is adopted March 01, 1994 by (Sgd.) Manuel F. Bruan, Brig. Gen. (AFP) Ret., Assistant Secretary.