Verification, Stamping and Inspection of weights and measures

Verification and Stamping of weights and measures are carried out as per provisions of the State Legal Metrology (Enforcement) Rules. Although these have been framed after the Model Enforcement Rules, they vary from state to state.



Verification is the process of comparing, checking, testing or adjusting a weight or measure to ensure that it conforms to the standard. Verification also includes re-verification and calibration.


It means a mark, made by impressing or casting and also includes affixing a paper seal, certifying that the weight or measure conforms to the standard set by the Act.

Standard Weight or Measure

Weights or measures which conform to the standard unit in accordance with metric system based on the international system and have the physical characteristics, configuration, construction, material, equipment, performance and tolerance as per Schedules of the General Rules are standard weights or measures.
[Section 8, LM Act 2009]

Principle of Verification

It is not enough merely to determine that the errors of equipment do not exceed the appropriate tolerances. Specification and user requirements are as important as tolerance requirements and should be enforced.

-- NIST Handbook of USA

Basics of Verification

  1. For first time verification, it is very important to ensure that the weight or measure conform to the physical characteristic, configuration and construction material specified in the Model Approval Certificate.
  2. The equipment should conform to the performance and tolerance as specified for the item given in the Schedules under the Legal Metrology (General) Rules, 2011
  3. For testing and checking an equipment, the Legal Metrology Officer shall use only valid working standard weight or measure. Un-verified and un-stamped working standards are not valid standards.
  4. The EUT (Equipment Under Test) should have a tolerance within the prescribed MPE (Maximum Permissible Error) as given under different schedules of the LM (General) Rules, 2011.

Provisions for Re-verification

  • Rule 27 of the LM (General) Rules, 2011
  • Rule 19 of the Model LM (Enforcement) Rules.

First time verification is done at the premises of the manufacturer. Subsequent verifications are normally done at the office or camp office of the LMO or at the premises of the user. After the initial verification, re-verification is necessary as per schedule.

Re-verification will also be required

  • After every repair
  • After the instrument is dismantled and reassembled for any purpose

Re-verification Schedule

Items Period
All weights, capacity measures, length measures, tape , beam scale, counter machine
24 months
Storage tanks
60 months
all other weight or measure including tank lorry
12 months

Fee for verification

Rule 16 of the Model Enforcement Rules for States.

  • Fees payable for verification and stamping will be as shown in the Schedule IX of the State Enforcement Rules. However, for verification at the place of use will be 1.5 times of the scheduled rate.
  • No additional fees will be charged for verification at the dealer's or manufacturer's premises.
  • Additional fees will also be not charged if the instrument is of such nature that it cannot be or should not be moved from its place of use.
  • If the weight or measure is not re-verified within the prescribed period, an additional fee of half the rate will be charged for every quarter of delay.
  • Full fee will be charged for re-verification or re-stamping within the prescribed period for weights and measures held in stock by a dealer or manufacturer provided that the original stamp was not obliterated. Earlier, no fee was payable.
  • The user shall pay expenses incurred by the LMO for visiting the premises of the user for verification. The minimum amount will be Rs. 100.

This Rule may vary from state to state


Sealing is done to secure the integrity of a weight or measure. All components, replacement, re-calibration or mal-adjustment of which might alter metrological characteristics of the instrument, are sealed. Sealing also prevents access to the calibration point of the instrument.

When sealing requires use of wire, only multiple threaded wire should be used and the sealing should be very tight.

List of points to be sealed is available in the User Manual and also in the Model approval Certificate. The LMO may also consider sealing additional points if considered necessary.


Rule 15 of the Model Enforcement Rules.
The stamping is done by impressing a punch mark on a permanently fixed stamping plate on the instrument or on the instrument itself. Punch mark or stamping is also made on the sealing points. A punch mark has 4 components - Name of the State, Identification no. of the LMO, quarter and year of verification.

Rule 20 of the Model Enforcement Rules.
Paper seal or Sticker may also be used for affixing verification mark on the instrument

Issue of Verification Certificate

Rule 15 (3 & 4) and 22 of the Model Enforcement Rules.
On completion of verification and stamping, the LMO will issue a Verification Certificate in the prescribed form. The Certificate should be prominently displayed at the place of use. A duplicate certificate, marked "DUPLICATE" will be available for Rs. 10.

Obliteration of Stamp

Rule 14(7) of the Model Enforcement Rules.
The LMO may obliterate a stamp, by punching over it a 8 pointed star punch, if it is found that

  • The weight or measure was not presented for re-verification although due.
  • Re-verification is not due but the instrument no longer conforms to the standard.
Such weight or measure may also be seized.

The LMO, in case of minor defects, instead of obliterating the stamp, may ask the user to remove the defects within eight days and after removal of the defects, may re-verify and stamp the instrument.

Provisions of the Legal Metrology Act, 2009

  • Section 16(1): Un-verified weights and measures are liable to be forfeited to the government.
  • Section 24(1): Every weight or measure must be got verified before use in any transaction or protection.
  • Section 33: Selling, distribution, transfer or using any un-verified weight or measure is punishable with a fine of Rs. 2,000 to 10,000. The subsequent offense is punishable with imprisonment up to one year and also with fine. The first time offense may be compounded.
However, if the person from whom the seizure was made, agrees to get the same verified within the time as may be allowed, the weight or measure will not be seized.
- Rule 23 of the LM (General) Rules, 2011


Section 55 of the LM Act, 2009

The provisions regarding verification and stamping of W & M will not be applicable in following cases;

  1. Used in factories manufacturing arms and ammunition for the use of Armed Forces.
  2. Used for scientific investigation or research.
  3. Manufactured exclusively for export