New MOT Diesel Smoke Limits for 2018


MOT sign, DVSA, vehicle testing


The DVSA have published a Special Notice which includes information about this topic.  It can be viewed here.

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The DVSA have announced new MOT Diesel Smoke limits will come into effect from 20 May 2018.

Here is a summary of the changes:

  • The addition of an extra vehicle category option available for selection by operators – vehicles first used on or after 1/1/2014 with a default test limit of 0.7m-1.
  • Addition of the facility to enter a user test value (manufacturers plate value) for all vehicle categories – where entered this will be the test value overriding the default value for the category.
  • Update the Fast Pass test value selection – a single default Fast Pass value will no longer be appropriate for all vehicles. The Fast Pass function will be retained, with either the test value being taken as the default value for the vehicle category or, where entered, the plate value. The Fast Pass test value will continue to be assessed against the first Free Acceleration Smoke output of the emission test
  • To ensure retention of lawful emission testing capability for diesel-powered vehicles, all Diesel Smoke Meters (DSMs) will require updating to incorporate the additional test limits and processes.

No further information is currently available as regards available updates from equipment manufacturers but we will be in contact with our clients when we have all of the details.