Requirements for Authorisation D Issue Date March 2019 35 3.2 Premises and Equipment 1. After approval of the site, every AE must, at all times, properly maintain the premises, facilities and testing equipment at all the VTSs for which they are responsible. The facilities and equipment include the following a. all facilities and equipment that were present at the time of the VTS's approval and any additions or alternatives that were agreed with DVSA by prior notification And b. all facilities and equipment required by any mandatory upgrade introduced by DVSA. 2. All testing equipment must be kept in good working order and measuring apparatus must be kept calibrated in accordance with DVSA’s requirements. Testing must stop on any class or type of vehicle, if any mandatory item of equipment falls out of calibration or malfunctions in away that could prevent a test being properly conducted on that class or type of vehicle. 3. An AE must apply to DVSA for approval prior to the changes being made for the following Addition of test classes to replace or modify any fixed test equipment that will alter the approved dimensions or layout alter the building or the layout of equipment The AE can apply using the VT application form on gov.uk. Supporting drawings should be enclosed with the application. No proposed change will be acceptable if it reduces clearances or dimensions (including those for access) below the limits specified in the Requirements for Authorisation or, for features approved only as acceptable variations, below their existing values. Any like for like changes to fixed test equipment must be notified to DVSA using the Change testing equipment link on the vehicle testing station page on the MOT testing service. Provided the notification has been given, the AE can proceed to have the equipment installed and use it. The changes will be checked by DVSA at the next visit. If the changes do not meet the Requirements for Authorisation approval may not be given. The renewal of mobile testing equipment does not have to be notified to DVSA provided that the replacement is on the current DVSA approved list and will not affect the range of vehicles that can be tested.