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Hampshire Trading Standards

Public Weighbridge Operators

This advice is designed to provide basic guidance to traders. It is not a complete or authoritative statement of the law.

What operators need to know

Operators of public weighing equipment have responsibilities to ensure that they can perform their duties competently and honestly. 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 a Trading Standards Officer and will be required to show that they can

a) operate the weighbridge satisfactorily
b) complete any weighbridge tickets and associated documentation satisfactorily
c) understand basic terms associated with the operation of a weighbridge
d) understand their duties as a weighbridge operator
e) understand potential frauds which may unknowingly be assisted by a weighbridge operator
f) understand how the accuracy of the weighbridge may be affected
g) perform simple arithmetic.

Before applying for a test, please ensure that you have received sufficient training in the operation of the equipment.

The scope of an operators certificate is limited to the type of weighbridge he/she will be expected to use. Should the weighbridge be replaced, a new certificate will be required.

Good Weighing Practice

  • Annex 1 contains a glossary of terms associated with public weighing and in Annex 2 there is a brief summary of the legal requirements.

  • Regular checks should be made to ensure 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 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 this 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 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.

It is good practice to note on the weighing certificate if any parts of a vehicle are missing. It is not unusual when weighing for taxation purposes for seats, spare tyres and even batteries to be removed in order to get the weight down to a lower category.

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 on 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 while 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 among the stated load. This heavy article can then be discarded and the goods delivered to a purchaser. e.g. 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 to be below the permitted legal weight for overloading purposes.

  • It is illegal to undertake a double weighing where that weighing will be used for a trade transaction. e.g. 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. The ticket should be endorsed - “Weights found are not for trade purposes”.

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).

  • The weight found must be entered in the GROSS or TARE box on the weighbridge ticket as appropriate.

  • If the ticket is to be issued, 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 determined by the Weighbridge Operator should be inserted. Gross and tare weights should only be entered on the same ticket if ascertained on the same day.

  • 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.

  • The other particulars required on the ticket must always be completed.

NOTE: Often when using an electronic headwork with a ticket printer, the information is fully or partly 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 a least 2 years. If the duplicate of the weighbridge ticket is the only record of the weighing, it must also state:

  • The date and time of weighing

  • The registration number of the vehicle or other identifying mark (e.g.; chassis number)

  • The weight found

  • 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)

While not strictly a matter for a certificated 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 overloaded’.

A weighbridge operator does not have authority to

  • withhold the weighbridge ticket

  • prevent the vehicle leaving

Self Assessment

Now you have read this factsheet we suggest you assess your level of knowledge using the questionnaires in Annex 3.


Annex 1 Glossary of Terms


When the weighbridge is unloaded the indication shows zero.

Gross Weight

This is the weight of the vehicle fully laden, and is an indication of the total weight of everything on the bridge.


Gross Vehicle Weight

Tare Weight

The weight of the vehicle after the load has been removed.

Net Weight

Gross weight less tare weight i.e. the weight of the load.

Train Weight

Similar to gross weight and refers to the all-up weight of any vehicle and trailer. On weighbridge documentation it may still be referred to as gross weight.


Gross Train Weight


The part of the machine which incorporates the weight indications.

Bottom Work

The levers and/or loadcells below the plate.


The part of the machine on which the load to be weighed is placed.


The weighing of a load or vehicle in two or more stages e.g. where an articulated vehicle cannot fit onto the plate its weight is calculated from the sum of the front and rear sets of axle weights.

Axle weighings

The weighing of individual axles or groups of axles to determine the load placed upon them.

Draw Bar Unit

A rigid vehicle towing, by means of a bar, a self supporting trailer.

Permitted GTW )

The legal maximum weight permitted on the road.

Unladen Weight

The weight of a vehicle inclusive of the body and all parts, excluding water, fuel, batteries, tools and loose equipment.

110797 ISS1


Annex 2 Legal Requirements

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 Operators:

  1. must carry out a weighing on demand unless they have reasonable cause not to do so
  2. must carry out the weighing fairly
  3. must give to the person requiring the weighing a written statement of the weight found
  4. must make a record detailing:
  5. time
  6. date
  7. particulars to identify the vehicle and its load
  8. the weight found.
  9. must not make a false record or give a false statement
  10. must not commit any fraud.

Persons bringing an item to be weighed must, if requested, give their name and address to the Operator. Records of weighings must be retained for two years. A record must not be destroyed or defaced within two years. No person may carry out a ?double weighing? for trade purposes.


Annex 3 Self Assessment Sheet

If you are unable to answer the following questions we would recommend you re-read the factsheet and discuss the matter with your supervisor.

  1. Can you confidently operate the weighing equipment?
  2. Where are the ‘copy ticket’ or records retained?
  3. Can you refuse to undertake a public weighing?
  4. If YES to (3), when?
  5. What details must be shown in the ‘records’’
  6. Would you weigh a ‘horse’’
  7. How long should records be retained?
  8. What do you understand by the terms
  9. Balance
  10. Net weight
  11. Double weighing
  12. What will happen to ‘balance’ when it rains?
  13. What will you do if passengers refuse to get out of a vehicle?
  14. If you cannot see the load, what will you do?
  15. The vehicle is too long to fit onto your weighbridge plate. What will you do?
  16. Why should you never leave blanks on a weighbridge ticket?
  17. Why 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.

110797 ISS1.


How do I apply?

Who to contact

  • Hampshire Trading Standards on the telephone number given.

Who can apply

  • An individual may apply or a company on his/her behalf.


  • No fee for test or issue of certificate.

How quickly will my application be processed

  • Contact will be made within 5 working days.



B/wei/041/003 October 2009

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