Safety inspection intervals and the records you must keep
Your inspection interval is a decision you must be able to justify, not a number copied from another operator. Here is how the DVSA expects it to be set and evidenced.
· 8 min read
Setting the frequency of Preventive Maintenance Inspections is among the most consequential compliance decisions an operator makes. The DVSA position is unambiguous: operational convenience must never override safety.
Inspections must be scheduled on a realistic, risk-based footing that reflects how quickly each vehicle actually deteriorates in your operation. This guide covers how to set that interval, and what you must keep to prove you met it.
The interval range
The Guide to Maintaining Roadworthiness — which refers to PMIs as safety inspections — states that intervals should normally fall between four and thirteen weeks, depending on the vehicle and its operating conditions.
That range is a framework, not a menu. You must be able to evidence why your chosen interval is appropriate for each vehicle you run.
| Operating conditions | Typical interval |
|---|---|
| Lightly loaded, easy conditions (motorway trunking, light loads) | 10–13 weeks |
| General haulage, mixed work (long-distance and local, varied loads) | 6–10 weeks |
| Arduous work, constant heavy loads (aggregates, timber, refuse) | 4–6 weeks |
| Off-road or severe conditions (quarries, construction, land reclamation) | 4 weeks |
| Vehicles and trailers over 12 years old | 6 weeks minimum |
That last row is not a suggestion. National data shows MOT failure rates and in-service defects rise significantly with age, and any vehicle or trailer aged 12 years or older must be inspected at least every six weeks regardless of the wider system in place.
Why 13 weeks is the wrong default
Thirteen weeks is the far end of the range, appropriate for lightly loaded vehicles in genuinely easy conditions. It is also, predictably, the interval most often chosen by operators who have not thought about it — because it is the cheapest and involves the fewest inspections.
An examiner comparing a 13-week interval against a tipper working construction sites is not going to accept it, and the difficulty is not merely that the interval was too long. It is that the operator cannot explain how the figure was arrived at, which suggests the maintenance system was never designed at all.
Be ready to answer: why this interval, for this vehicle, doing this work?
Mileage-based and mixed systems
Mileage-based or mixed approaches suit more experienced operators, particularly where vehicles are frequently reassigned or a fleet changes continuously, making a strictly time-based programme impractical.
You may run more than one system across a fleet — time-based for some vehicles, mileage-based for others, or different approaches for individual vehicles. Where you do, you must indicate on the Vehicle Operator Licensing (VOL) system that some vehicles are inspected more often than the stated maximum interval.
Example. An operator records a maximum interval of 10 weeks on VOL. Most of the fleet runs to that cycle, but three vehicles are over 12 years old and are inspected six-weekly. VOL still shows 10 weeks as the maximum; the operator answers "yes" to the question about more frequent inspection of some vehicles, and retains evidence of the six-weekly schedule.
Example. An operator normally inspects eight-weekly, with vehicles covering around 1,000 miles a month on regional work. A new contract puts three vehicles on national deliveries covering up to 3,000 miles a fortnight. Those three switch to inspection every 2,000 miles or six weeks, whichever falls first. The fleet maximum on VOL remains eight weeks, with the mileage-based system recorded and evidenced.
ISO week planning
DVSA recommends scheduling by ISO week number. Each week runs from midnight Monday to midnight Sunday, and week 1 is the week containing the first Thursday of the year.
The benefit is consistency with a degree of practical flexibility: provided the inspection is carried out within the correct ISO week, it is on time. A vehicle first inspected in week 10 on a six-week interval is next due in weeks 16, 22, 28, 34 and so on — and an inspection due in week 22 may be carried out any day from Monday to Sunday of that week.
This matters more than it sounds. Operators working to exact dates routinely record inspections a few days late for entirely ordinary reasons, and a pattern of late inspections reads badly whatever the explanation.
Brake testing
A laden roller brake test is expected at safety inspection, or within a short window around it. Where loading was genuinely impracticable, a competent person must have assessed that and recorded the assessment.
Unladen tests filed without comment or justification are a frequent finding. The test result itself also needs reading rather than filing: a report showing declining performance across successive inspections is telling you something, and an examiner will notice it even if you did not.
The records you must be able to produce
For each vehicle and trailer:
- Safety inspection records for every inspection, showing what was checked, by whom, the condition found, and what was done about it
- Brake test records, laden where practicable, with a recorded assessment where not
- Defect reports from drivers, with the corresponding rectification recorded
- Repair and invoice records that reconcile to the defects and inspections they relate to
- The inspection schedule itself, showing planned dates and actual dates
The reconciliation point is where otherwise diligent operators come unstuck. Each document may be present and correct, but if an inspection sheet records a defect and no repair record corresponds to it, the file raises a question rather than answering one. Examiners follow individual defects through the paperwork from report to rectification, and gaps in that chain are what they are looking for.
Who may carry out inspections
Inspections must be carried out in a suitable environment, with appropriate facilities, by people competent to do the job. You may use a third-party maintenance provider — most small operators do — but doing so does not transfer the obligation. You remain responsible for the quality of the work, the adequacy of the records and the intervals being met.
If you contract maintenance out, you should still be reading the reports that come back.
Where to check for yourself
- Guide to Maintaining Roadworthiness — inspection intervals, records and the maintenance standard
- Being a goods vehicle operator — the undertakings your licence carries
"Why this interval, for this vehicle, doing this work?" is a question our customers can answer, because we set the interval with them and record the reasoning. At TMassist we hold your PMI schedule, MOT dates and insurance renewals centrally and raise each one with you in advance, then read the inspection sheets and brake test reports that come back — so a declining brake performance trend gets noticed by us rather than by DVSA. Booking the work, and maintaining the vehicles, remain your responsibility.