Public Weighbridge Operator's certificate

To operate a public weighbridge, you must have a certificate of competence issued by our Chief Weights and Measures Inspector and you must have sufficient knowledge for the proper performance of your duties.

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Qualifications required

Operators of public weighing equipment have responsibilities to ensure that they can perform their duties competently and honestly. Further, no one may operate public weighing equipment unless he/she holds a certificate from a Chief Trading Standards Officer.

Applicants for a certificate will be tested verbally and practically by an Inspector and will be required to show that they can:

  • Operate the weighbridge satisfactorily
  • Complete any weighbridge tickets and associated documentation satisfactorily
  • Understand basic terms associated with the operation of a weighbridge
  • Understand their duties as a weighbridge operator
  • understand potential frauds which may unknowingly be assisted by a weighbridge operator;
  • understand how the accuracy of the weighbridge may be affected; and
  • perform simple arithmetic (use of a calculator is permitted).

How do I apply?

Before applying for a test, please ensure that you have received sufficient training in the operation of the equipment and that you have completed the application form. This document will be required by the inspector when he or she tests you.

Public Weighbridge Operator's Application Form

It is the policy of this authority to limit the scope of any certificate to the weighbridge the operator will be expected to use. Should the weighbridge be replaced or changed, a new certificate will be required.

What is the cost?

Please refer to our hourly rate on our fees list

Weights and Measures Act 1985

  • Section 18 – Operators of public weighing equipment must hold a certificate of competence from a Chief Trading Standards Officer.
  • Section 20 (i) must carry out the weighing on demand unless they have reasonable cause not to do so.
  • Section 20 (ii) must carry out the weighing fairly
  • Section 20 (iii) must give to the person requiring the weighing a written statement of the weight found
  • Section 20 (iv) must make a record detailing:
    • Time
    • Date
    • Particulars to identify the vehicle
    • Identify the load on the vehicle
  • Section 20 (v) must not make a false record or give a false statement
  • Section 20 (vi) must not commit any fraud
  • Section 20 (vii) persons bringing an item to be weighed must, if requested, give his name and address to the operator
  • Section 20 (viii) records of weighings must be retained for two years
  • Section 20 (ix) records must not be destroyed or defaced within two years.

Weighing Equipment (EEC Automatic Weighing Machines) Regulations 1988

Regulation 4 (7) no person may carry out a 'double weighing' for trade purposes.


  • Balance is when the weighbridge is unloaded, the indication shows zero
  • Gross weight is this is the weight of the vehicle fully laden and is an indication of the total weight of everything on the bridge
  • GVW is Gross Vehicle Weight
  • Tare weight, this is the weight of the unladen vehicle like the weight you will use to calculate the vehicle's load
  • Net weight is gross weight less tare weight in other words the weight of the load
  • Train weight is similar to gross weight and refers to the all-up weight of an articulated vehicle (tractor and trailer). On weighbridge documentation, it will still be referred to as gross weight
  • GTW is Gross Train Weight
  • Headwork is the part of the machine which incorporates the weight indications
  • Bottom work is the levers and/or load cells below the plate
  • Plate or Platform is the part of the machine on which the load to be weighed is placed
  • Double-weighing is the weighing of a load or vehicle in tow or more stages for example where an articulated vehicle cannot fit on to the plate, its weight is calculated from the sum of the front and rear sets of axle weights
  • Axle weighings is the weighing of individual axles or groups of axles to determine the load placed upon them
  • Draw bar unit is a rigid vehicle towing, by means of a bar, a self supporting trailer
  • Permitted GVW is the legal maximum weight permitted on the road
  • Permitted GTW is the legal maximum weight permitted on the road

Good weighing practice

Regular checks should be made to ensure that there is clearance between the plate and its surrounding frame. If the weighing machine operates using a lever bottomwork, the plate should swing freely endways.

Regular checks should be made to ensure that the weighbridge is properly balanced when unloaded and the indicator shows zero.

The weighbridge operator must know how to balance the weighing machine

The balance of a weighbridge will be affected by the accumulation of dirt etc on or around the plate. This should be regularly cleaned to avoid any excessive build-up.

Beneath the plate, levers or load cells may be affected by the build-up of dirt (sand) and should be cleared as necessary. If your weighbridge is prone to such contamination, a regular maintenance programme should be implemented.

In a pit mounted weighbridge, balance and accuracy may be affected by a high water level in the pit which 'floats' the levers or the bottomwork. In such circumstances, pumping facilities should be available and the weighbridge operator will be expected to know how to use it.

The most common cause of 'balance' error is due to rain on the plate. During periods of rain, balance should be checked and adjusted more frequently and again as the plate dries.

Weighing procedures

It is advisable to weigh all vehicles without passengers or driver. If this is not possible or if the personnel refuse to leave the vehicle, a note should be made to this effect with details of the number of persons in the vehicle. This note should be made on the ticket and on any other record. This information is required because certain persons may wish to increase the gross weight of the load by addition of passengers and, if and when the tare weight is taken without passengers, the weight of the load appears heavier.
Weighbridge operators should take special care whilst passengers are on or in the vicinity of the plate.

Where practical, the weighbridge operator should check the load for himself and, if this is not possible, the ticket should indicate the load as stated by the driver.

Weighbridge operators should be aware that persons bringing loads to be weighed may conceal heavy items amongst the stated load. This heavy article can then be discarded and the goods delivered to a purchaser for example concrete blocks with scrap metal - the load is identified as scrap metal and following weighing, the concrete is discarded and the scrap metal sold at the
higher weight. Therefore, the weighbridge ticket would be properly completed as 'scrap metal/concrete'.

The operator should always check any vehicle registration number for himself rather than rely on the driver.

The weighbridge operator should have a clear view of the plate and ensure the vehicle being weighed is positioned on the plate. Weighbridge operators should be aware that persons requiring a weighing may deliberately leave a wheel over the edge of the plate to reduce the weight shown. This is either done to reduce the tare weight (and therefore increase the apparent weight of
the load) or to appear below the permitted legal weights for overloading purpose.

It is illegal to undertake a double weighing where that weighing will be used for a trade transaction for example a load of hay for sale elsewhere.

Drivers sometimes require a weighing to ensure they are not overloaded on individual axles.

It is permissible to undertake weighings of individual axles but the ticket and records should clearly indicate what type of weighing was carried out and which axles were weighed etc.

The ticket should be endorsed 'weights found are not for trade purpose'.

Weighbridge ticket

A weighbridge operator must give a statement in writing of the weight found to the person demanding the weighing or to his agent (this may be an arrangement made formally or informally but the statement should always go with the vehicle).

They must enter the weight found in the gross or tare box on the weighbridge ticket as appropriate.

If the ticket is to be issued, then the weighbridge operator must enter not weighed or draw lines through the spaces provided for other entries. Operators must not enter in the tare box a weight stated by the driver, as only weights determine by the
weighbridge operator should be inserted.

If the driver intends to return after loading for a second weighing of the same vehicle to be recorded on the same ticket, the ticket should be retained until the second weighing is complete. A weighbridge operator should never give out a ticket that has
any blank spaces. They must complete the particulars required on the ticket.

Note, often when using an electronic headwork with ticket printer, the information is fully or partially transferred onto the ticket. However, if this fails, full records must still be kept and any calculations worked out accurately.


The weighbridge operator must ensure that a record of each weighing is made. These records must be kept for at least two years. If the duplicate of the weighbridge ticket is the only record of the weighing. It must also state:

  • The time of the weighing
  • The registration number of the vehicle (if applicable)
  • The weight found
  • The date
  • The nature of the load.

If a weighbridge operator suspects any irregularities in a request for, or the use of, public weighbridge weighings, their local Trading Standards office should be informed.

The maximum penalty for fraud in connection with a public weighing is a fine of £5,000 or six months' imprisonment, or both. The maximum penalty for recording a false weight is a fine of £5,000.

Road Traffic Act (Vehicle Overloading)

Whilst not strictly a matter for a certified weighbridge operator, this authority would expect an operator to have a basic knowledge of vehicle weights.

If, having weighed a vehicle, a weighbridge operator suspects the weights to be in excess of that permitted for the vehicle on the highway, they should draw the driver's attention to the weight record. Further, the ticket should be marked 'vehicle possibly

A weighbridge operator does not have authority to:

  • Withhold the weighbridge ticket; and/or
  • Prevent the vehicle leaving.

Self assessment sheet

If you are unable to answer the following questions, we would recommend you reread the booklet and discuss the matter with your supervisor.

  • Can you confidently operate the weighing equipment?
  • Where are the 'copy ticket' or records retained?
  • Can you refuse to undertake a public weighing?
  • If yes to the above questions, when?
  • What details must be shown in the 'records'?
  • Would you weigh a 'horse'?
  • How long should the records be retained?
  • What do you understand by the terms:
    • Balance?
    • Net weight?
    • Double weighing?
  • What will happen to 'balance' when it rains?
  • What will you do if passengers refuse to get out of a vehicle?
  • If you cannot see the load, what will you do?
  • The vehicle is too long to fit onto your weighbridge plate. What will you do?
  • Why should you never leave blanks on a weighbridge ticket?
  • Whey should 'people' bringing articles for weighing try to mislead you.

In preparing for your test, please expect additional questions to those detailed above as these are for your benefit to judge your readiness.

Weighbridge locations and permitted vehicle weights

Please see for information on HGV maximum weights and to find your local weighbridge.

What if I have any queries, concerns or complaint?

This information is designed to give you general advice. It is not a statement of law and should not be interpreted as such. For further details, please contact us.

Our Business Advice line is available Monday to Friday from 9am to 5pm (Bank holidays excluded)

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