The Periodic Smoke Inspection Program
The Periodic Smoke Inspection Program was adopted into state law in 1990 to
control excessive smoke emissions and tampering in all California-based on-road
diesel trucks and buses. With enforcement focused more heavily on the trucking
industry, the PSIP was enacted to promote self-inspection of on-road diesel
vehicles. While the state allows "self-inspection", there are specific standards
that must be met that would likely make it more cost effective for small fleet
owners to take the vehicles to a
facility (PDF) that
offers the PSIP test instead of conducting a "self-inspection."
Owners of on-road diesel vehicles are not required to inspect vehicles that
are powered by diesel engines until their fourth model year. For example, 2007
model-year engines must have their first test completed by Jan. 1, 2011. All
testing must conform to the Society of Automotive Engineers J1667
snap-acceleration test procedure and all testing must be performed using an SAE
J1667 smoke meter.
In October 2010, a number of changes were made that essentially break the
PSIP into four different ways to regulate your vehicles depending on the age and
gross vehicle weight rating (GVWR) of your diesel vehicles. You only need to
comply with the one option that applies to your situation. The new changes are
listed below in the first two points. If neither of these scenarios applies to
you because of the size of your vehicle or where you live, then the third or
fourth point (which is the original PSIP program) would apply.
- If you own one or more 1998 and newer diesel powered
on-road vehicles garaged in an
of the state with a GVWR of 6,001 to 14,000 pounds, you
are NOT subject to the requirements of the PSIP any longer. You ARE now subject
instead to biennial smog check inspections. You will receive the notification of
your smog check requirement through the DMV registration process as you do with
your passenger cars. The smog check requirement applies to every diesel vehicle
of this size and age while all the other PSIP requirements apply only if you own
two or more vehicles that are NOT exclusively for personal use.
- If you own two or more 1998 and newer diesel powered
on-road vehicles garaged in an
of the state with a GVWR of 6,001 to 14,000 pounds, you are
NOT subject to biennial smog check inspections but you
ARE required to have a passing PSIP inspection on a
BIENNIAL basis. Vehicles with a VIN ending in an odd number
will be tested during years ending with and odd number and vehicles with VINs
ending with an even number will be tested during years ending with an even
number. By living in a region with cleaner air (air quality attainment area) you
only have to have a PSIP test every two years instead of annually.
- If you own two or more 1997 model year or earlier diesel
powered on-road vehicles with a GVWR over 6,001 pounds you are still subject to
ANNUAL PSIP inspection and record keeping requirement
regardless of where you live. Diesel and bus fleet owners must conduct annual
inspections, repair vehicles with excessive smoke emissions and maintain two
years of inspection/repair/retest records. Those records could be requested for
review during random audits conducted by a representative of the California Air
- If you own two or more diesel powered on-road vehicles with
a GWVR greater than 14,001 pounds you are still subject to the ANNUAL PSIP
inspection and record keeping
regardless of the model year or where you
. Diesel and bus fleet owners must conduct annual inspections,
repair vehicles with excessive smoke emissions and maintain two years of
inspection/repair/retest records. Those records could be requested for review
during random audits conducted by a representative of the California Air
Emission Control Labels Required
All of these diesel truck engines need to be equipped with an "Emission
Control Label" that verifies that the engine meets California emission
standards. These labels are put on the engines when they are manufactured. If
the label is missing or not readable, regulators may impose an additional
penalty. An authorized dealer should be able to help replace an engine label if
one is needed.
Who is exempt from PSIP?
If you only own one on-road diesel vehicle weighing over
6,001 GVWR then you are exempt from the annual
of your model year or where the vehicle is garaged (where you live). PSIP is
required when you own two more on-road diesel vehicles over 6,001 GVWR that are
used for non-personal uses.
Example: if you had one on-road diesel vehicle that weighed 7,000 GVWR and
you used exclusively for personal use and one on-road diesel vehicle that
weighed 26,500 GVWR that is used on the farming operation then neither of these
vehicles would need a PSIP. But if you have two diesel vehicles over 6,001 GVWR
that are used at any time for non-personal, commercial purposes (i.e. your
farming operation) then both vehicles would need an annual PSIP.
Smog Check and PSIP are different programs
Smog check will still be required of every on-road diesel
vehicle from 6,001 to 14,000 GVWR that are 1998 or newer after their fourth
model year regardless of use that is garaged in a nonattainment area. For
example, a 2007 model year would have to be smog checked in 2011. You will be
notified through your registration when you need to obtain a smog check.
For more information visit PSIP or the Truck Stop page
of the California Air Resources Board for on-road diesel vehicle inspection
programs and requirements. Online information includes an instruction manual,
self-certification forms and instructions, lists of smoke testing facilities and
more. If you have general program questions, contact David Gray at the CARB
Sacramento office: (916) 327-9473.