Rule 14 explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
Rule 14 is one of the shortest rules in the General Rules. It says the procedure for calibrating vehicle tanks and similar tanks is whatever the Ninth Schedule specifies. The rule is a single sentence; everything of substance is in the Schedule, which has three Parts. If you run tank lorries or oil storage, a legal consultation can help you work out which Part of the Schedule applies to you.
Rule 14 says that "the procedure for carrying out calibration of vehicle tanks, etc. shall be as is specified in Ninth Schedule". The Ninth Schedule has three Parts: calibration of vehicle tanks for petroleum products and other liquids (Part I); method for calibration of vertical oil storage tanks (Part II); and method for computation of capacity tables for vertical oil storage tanks (Part III). The rule gives no form, fee or time limit. For vehicle tanks, the Schedule sets a maximum error of 0.05 per cent in excess of the marked capacity of a compartment.
The text of rule 14
The heading is "Procedure for carrying out calibration of vehicle tanks, etc." and the text is: "The procedure for carrying out calibration of vehicle tanks, etc. shall be as is specified in Ninth Schedule."
That is all. Rule 14 follows the rules on weights, measures and instruments. It works by reference, in the same way as rules 11, 12 and 13, but with a difference: those rules lay down a standard that the object must meet, while rule 14 lays down a procedure, namely how calibration is to be carried out.
Four things the rule does not say:
- It does not say who carries out the calibration.
- It does not say how often a tank must be calibrated.
- It does not set a fee or a form.
- It does not define "etc." The Schedule's Parts show that vertical oil storage tanks are included.
The periodic re-verification of tanks, including tank lorries, is dealt with in rule 27 and the Act's verification rules in section 24.
The Ninth Schedule at a glance
The Schedule is headed "Procedure for carrying out calibration of vehicle tanks, etc." (marked "See Rule 14").
| Part | Title | What it covers |
|---|---|---|
| I | Calibration of vehicle tanks for petroleum products and other liquids | Definitions, testing medium, equipment, calibration procedure, maximum error, marking and the vehicle plate |
| II | Method for calibration of vertical oil storage tanks | Scope, conditions for measurement, record form, circumference and vertical measurements, deadwood, tilt |
| III | Method for computation of capacity tables for vertical oil storage tanks | Scope, general principles, form of tank tables, corrections, calculations, deadwood |
Part I: vehicle tanks
Part I defines a vehicle tank as an assembly used for measurement and delivery of liquids, comprising a tank (which may be sub-divided into compartments) mounted on a vehicle with its piping, valves and meters. Calibration, in this Part, means verification and stamping of the capacity of the vehicle tank or its compartments. It also defines the dip stick, ullage stick, ullage indicator, proof level and dip pipe.
- Testing medium. Water or another appropriate liquid is used to find a compartment's capacity. A vehicle tank meter is tested with a liquid of the same character or about the same viscosity as the liquid it will measure.
- Equipment. Proving measures checked against a working standard measure, a calibrated bulk meter fitted with a pre-set valve, air eliminator and strainer, a set of standard commercial measures, and tools such as a hose, scriber, punch and try square.
- Procedure. A tank used as a measure is calibrated as a capacity measure; where it has a meter, the meter is treated as a separate measuring instrument. The compartment capacity includes the delivery lines up to the outlet valve, except where a compartment ends in a single delivery pipeline with an outlet valve; a notice on the vehicle tank must say whether the marked capacity includes or excludes the delivery line. The vehicle is placed level, tyres are at the correct pressure, pipelines are tested for leakage, and each compartment is filled to its marked capacity and the dip or ullage mark is cut on the stick.
- Maximum error. The Schedule gives a table of capacities and permissible errors for proving measures (the printed figures are not reliable in the scan, so read them in the official text). For compartments, the maximum error is 0.05 per cent in excess of the marked capacity.
- Marking. The vehicle carries a brass plate with a space for the Legal Metrology Officer's stamps. It shows the owner's name, the vehicle registration number, and the serial number and capacity of each compartment. Capacity is also marked on the manhole cover and painted on each side, and the vehicle number and compartment details are marked on the dip or ullage stick.
Part II: vertical oil storage tanks
Part II prescribes calibration of vertical tanks by strapping and internal measurements, for tanks meant for bulk storage of petroleum and liquid petroleum products. Measurements are taken only after the tank has been filled at least once at its present location, to its working capacity (with product or with water to the equivalent height), and held for at least 24 hours to allow for settling. It deals with interrupted measurements, descriptive data (with a recommended Tank Measurements Record Form), measurement of circumference or diameter, vertical measurements, deadwood and measurement of tilt.
Part III: capacity tables
Part III prescribes how to compute capacity tables for the same class of tank. Each table must state that the dip and capacity relationship applies only to dips taken at one specified, marked point, and the height of the dipping reference point is recorded at the head of the table. The Part recommends dip intervals not greater than 5 cm, notes that tables should not show fractions of a litre, and then sets out corrections to measured data, calculations of capacity, corrections to diameter and treatment of deadwood. A specimen table form with space for approval, date and signature closes the Schedule.
The detailed calculation steps and worked tables are technical and partly garbled in the scan. Use the Schedule as notified in the Gazette (G.S.R. 11(E), 7 February 2011) or a reliable official copy, and check later amendments.
Where calibration sits in the Act
The General Rules are made under the Act's rule-making power, and section 52 and section 53 are the parent provisions. The Act requires verification and stamping of weights and measures before use in a transaction or for protection (section 24), and rule 27(2) sets re-verification periods that separately name storage tanks and tank lorries. A tank's calibration gives the capacity that is then verified, so the two rules operate together.
A practical point for owners: the Act allows the Central Government to prescribe kinds of weights and measures whose verification is to be done through a Government approved Test Centre, notified by the Central or State Government (section 24(2) and (3)). The sources used here do not list which kinds are so prescribed. Ask the Controller's office which route applies to your tank.
Who should care about rule 14
| Who | Why |
|---|---|
| Fuel and liquid transporters | Tank lorries need calibration and periodic re-verification before being used to deliver a measured quantity. |
| Oil depots and storage operators | Vertical oil storage tanks are the subject of Parts II and III. |
| Tank fabricators and repairers | The capacity and calibration of a fabricated tank is checked by the Schedule's method; a repairer's licence question is in section 23. |
| Buyers of bulk liquids | A buyer who relies on a tank reading relies on its calibration. |
Examples
Example 1: a new tank lorry. A transporter builds a new tank lorry body with three compartments. Before it is used to deliver a measured quantity of liquid, it is calibrated by the Part I procedure and stamped. The transporter needs the brass plate, the capacity marks on each compartment and the stamped dip stick, and should ask the Controller's office what papers to bring.
Example 2: a storage tank capacity table. An oil depot wants to use a capacity table for a vertical storage tank. Part III is the method for computing capacity tables, and Part II is the method for the measurements that feed it. The depot should use those methods and not a table made some other way.
Common mistakes
- Treating rule 14 as a rule with its own steps. The steps are in the Schedule.
- Assuming a calibration done years ago remains valid indefinitely. Re-verification periods apply under rule 27.
- Forgetting the notice on the vehicle tank about whether the marked capacity includes the delivery line.
- Relying on a summary instead of the notified Schedule.
Need help with tank calibration and verification?
If you operate tank lorries or storage tanks and want to check calibration, verification and records against the Schedule, or have received a notice, a legal consultation is a way to go through the papers with us.
Key takeaways
- Rule 14 is one sentence: calibration of vehicle tanks, etc. follows the procedure in the Ninth Schedule.
- The Schedule has three Parts: vehicle tanks, vertical oil storage tanks, and capacity tables.
- For vehicle tank compartments the maximum error is 0.05 per cent in excess of the marked capacity.
- The vehicle needs a brass plate for the officer's stamps and capacity markings.
- The rule sets no form, fee or frequency; periodic re-verification is in rule 27.
Read next
- How to Get Verification of Weights and Measures
- Re-Verification of Weights and Measures -- Periodicity
- Rule 13 of the Legal Metrology (General) Rules, 2011: Measuring instruments and the Eighth Schedule
- Rule 15 of the Legal Metrology (General) Rules, 2011: Registration of importer and the Tenth Schedule
Disclaimer: Based on the Legal Metrology (General) Rules, 2011 (G.S.R. 11(E), 7 February 2011) as notified in 2011, read with the Legal Metrology Act, 2009 (Act 1 of 2010), the Jan Vishwas (Amendment of Provisions) Act, 2023 (in force) and the Jan Vishwas (Amendment of Provisions) Act, 2026 (in force only from the date the Central Government notifies), as on 30 September 2026. The Schedule text is the 2011 notification; later amendments, State Legal Metrology rules and notifications change; verify the current position before acting.