A rolling mill in Raipur producing IS 2062 plates received a pre-dispatch inspection visit from a TPI team engaged by a government project client. The factory QA manager had prepared the MTC packet, bundled the lab reports, and arranged the material for sampling. What the TPI team found in the first thirty minutes set the tone for the rest of the day: the test reports were from an in-house laboratory that wasn't NABL-accredited for tensile testing, the heat numbers on the MTC didn't match the heat numbers on the material tags, and there was no documented traceability chain from the melt shop to finished plate.
The inspection didn't proceed to sampling. The mill received a non-conformance report and had to restart the process with NABL-certified external lab results and corrected MTC documentation.
Why BIS Requires Third-Party Inspection
BIS product certification under IS 2062, IS 1786, IS 808, and other mandatory steel standards involves surveillance that the manufacturer cannot self-administer. The certification model is built around the principle that the certifying body — BIS — or its authorized representatives must independently verify that what the manufacturer claims is producing matches what is actually produced and tested.
For scheduled steel products, this surveillance takes two forms:
- BIS's own periodic factory visits (conducted by BIS officers)
- Pre-dispatch or in-process TPI by BIS-authorized agencies for specific project contracts
On large government infrastructure projects, TPI is typically a contract requirement that sits alongside BIS certification — not a substitute for it. The project owner requires both an ISI-marked material (confirming BIS certification) and a TPI inspection certificate (confirming this specific consignment was independently verified).
Which TPI Agencies Are Authorized
TPI for steel on government and infrastructure projects in India is carried out by agencies that hold BIS authorization, independent accreditation, or government recognition. Common agencies include Bureau Veritas, SGS India, Intertek, RITES (for railway projects), STQC (Standardisation Testing and Quality Certification), and CEIL (Central Engineering & Investigation Laboratories for some state projects).
The specific agency required depends on the project contract. NHAI contracts may name specific agencies. Defence procurement has its own Quality Assurance (QA) directorate structure. State PWD projects may list approved agencies in the tender document. Manufacturers and distributors need to check which agency is acceptable before arranging inspection — not all TPI certificates are interchangeable.
What TPI Agencies Check at the Factory
A properly conducted pre-dispatch TPI visit for BIS-certified steel typically covers four areas:
1. Documentation review The TPI team starts with papers, not material. They check:
- The BIS licence (CM/L number), its current validity, and scope — using the BIS portal, not just the document provided by the mill
- The MTC for the consignment: completeness, heat traceability, grade specification, test values against IS 2062 / IS 1786 / applicable standard limits
- The test report from the laboratory: lab name, NABL accreditation scope, test method references, date
- Purchase order against delivery documentation
2. Material identification and traceability Inspectors physically verify that the heat numbers on the MTC match the heat numbers on the material — on bundle tags, on cut plates, on bar rib markings. They check that the material in the dispatch bay corresponds to the documentation being presented.
3. Laboratory accreditation verification Test reports attached to the MTC must come from NABL-accredited laboratories whose scope of accreditation explicitly covers the tests required by the applicable IS standard. Inspectors verify:
- The NABL certificate number on the lab report
- That the NABL scope includes tensile testing, bend testing, and chemical analysis for steel
- That the tests were performed after the date of accreditation and before any lapse
4. Sampling and witness testing For some contracts, the TPI team collects samples from the consignment and either witnesses testing at the mill's NABL-accredited lab or arranges for samples to be dispatched to an independent NABL lab. Results are compared against the values on the MTC.
The Difference Between a TPI Report and a BIS Certificate
These are two separate documents serving two separate purposes.
The BIS certificate (CM/L number) belongs to the manufacturer and confirms that the manufacturer's production facility and quality system have been assessed by BIS. It covers the manufacturer, not a specific consignment.
The TPI inspection certificate is consignment-specific. It confirms that a qualified third party checked this specific batch — verified the documentation, confirmed traceability, and (where sampling applies) independently tested samples from this heat. It is issued per consignment, per project contract, and is usually addressed to the project client.
Government project specifications that require TPI are asking for both. ISI mark + BIS licence covers the manufacturer. TPI certificate covers the shipment.
How to Prepare for a TPI Visit
Manufacturers and fabricators who face TPI visits regularly maintain a pre-inspection readiness checklist:
Documentation ready before the inspector arrives:
- Current BIS licence certificate (not a photocopy from a year ago — print a fresh portal confirmation)
- MTC for the specific consignment with all required fields completed
- NABL lab test report with test report number, accreditation details, test method references
- Heat number register showing chain from melt to finished product
- Bundle or plate tags on the physical material matching the MTC heat numbers
- Calibration records for in-house testing equipment if any in-house tests are referenced
Material ready:
- Consignment segregated clearly, with tags accessible
- No mixed heats in the same dispatch area unless separately tagged and documented
- Clear markings (ISI mark visible on plates or rib markings on bars)
People ready:
- QA manager present and available for the full duration of the inspection
- Access to the testing laboratory records without delay
- Contact number for the NABL lab if the inspector wants to verify test details directly
A TPI visit that is well-prepared typically takes a few hours. One that requires the factory team to hunt for documents, reprint MTCs, or explain inconsistencies in heat numbers can stretch into the next day — and may end with a hold notice instead of a clearance certificate.