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  • Mitsubishi Fuso Authorized Dealer
    Established 1967
  • 1505 N 4th St. San Jose, CA
  • 408-263-7300
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Bay Area Opacity Testing

California and Bay Area Opacity Testing

Since 1999, the California Heavy-Duty Vehicle Inspection Program has required heavy duty trucks and buses (gross vehicle rating over 6000 lbs.) to submit to opacity testing administered by the California Air Resources Board (CARB). Opacity testing measures the amount of light that is blocked by particulate matter and smoke in diesel exhaust.

Opacity Tests, Inspections, and Recording

San Jose and Bay Area Opacity Testing consists of:

  • RPM Recording at idle and maximum governed speeds
  • The Snap-Acceleration test
  • Visual Inspection for visible signs of tampering

Opacity Testing in our shop:

  • Truck: $109
  • Bus: $149
  • Mobile Opacity Testing is available. Call for quote.

Allowable levels:

  • All 1991 or newer engines must not exceed 40% smoke opacity
  • All pre-1991 engines must not exceed 55% smoke opacity

Tests may be performed unannounced at:

  • ACHP weigh stations
  • A random roadside locations
  • Fleet facilities
PSIP for California and Bay Area Opacity Testing

A complementary program called the Periodic Smoke Inspection Program (PSIP) requires that all heavy duty trucks and buses plated in California that are more than four years old have tampering inspections and opacity testing yearly. Every vehicle must have two years of California or San Jose Opacity Testing records or be cited.

Citation for California and San Jose Opacity Testing Failure

Pre-1991 vehicles with opacities greater than 55% but less than 70% without citations in the last 12 months receive of notice of violation. Repairs must be made and a Demonstration of Correction form must be submitted within 45 days or a citation will be issued.

First Level Citation
  • $300 for pre-1991 engines with 70% or greater smoke and no citations in the past 12 months
  • $300 for 1991 and newer engines with 40% or greater smoke and no citations in the past 12 months
  • The penalty for both engine types increases to $800 if a Demonstration of Correction form is not submitted to the CARB within 45 days
Second Level Citation

Penalty for any further violations within 12 months is $1800.

Diamond Service is a Certified Bay Area Opacity Testing location and we can come to you. Call us at 408-263-7300 for an appointment.

For more information, you can download these PDFs:
California’s Heavy-Duty Vehicle Inspection Program (HDVIP)
California’s Periodic Smoke Inspection Program (PSIP)

Mitsubishi Fuso Authorized Dealer

Hours of Operation:

Mon – Fri: 8:00AM – 5:00PM

Weekends or After Hours by Appointment

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Diamond Mitsubishi Fuso

1505 N 4th St. San Jose, CA 95112

(408) 263-7300


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