Division 4.3 F1
United Kingdom
The manufacturer shall be authorised, under the supervision of the approval authority, to carry out checks, even of a destructive nature, on those vehicles with emission levels in excess of the limit values with a view to establishing possible causes of deterioration which cannot be attributed to the manufacturer (e.g. use of leaded petrol before the test date). Where the results of the checks confirm such causes, those test results shall be excluded from the conformity check.