A quality engineer at a fabrication shop in Pune was reviewing a supplier's mill test certificate for IS 2062 E250 plates. The MTC showed chemical composition, mechanical test results, and a statement that the material conforms to IS 2062. The engineer stamped it approved and moved the plates to the cutting floor.
Three weeks later, a third-party inspector on a CPWD project rejected the material. The reason: the project specification required ISI-marked material. The plates had no ISI mark. The MTC — while technically accurate — was a manufacturer's self-declaration, not BIS certification.
This distinction costs fabricators time, money, and project delays more often than it should.
What an IS 2062 Mill Test Certificate Actually Is
A mill test certificate (MTC) for IS 2062 is a document the producing mill generates to show that the material it shipped meets the IS 2062 standard for chemical composition and mechanical properties. The mill runs the tests — or has them run at a lab — and issues the document.
The key word is "self-declaration." The mill is stating that its product meets the standard. There is no mandatory third-party verification of the MTC before it leaves the mill. A non-BIS-certified mill can legitimately issue an IS 2062-compliant MTC if its product meets the specified properties.
What the MTC typically contains:
- Heat number and cast number
- Chemical analysis (C, Mn, S, P, Si)
- Mechanical test results (yield strength, UTS, elongation, bend test)
- Plate dimensions, thickness, weight
- Reference to IS 2062 and the applicable grade
What a standard IS 2062 MTC does not contain, unless the mill holds BIS certification:
- BIS license number (CM/L number)
- ISI mark reference
- Third-party verification
What BIS Certification Actually Is
BIS product certification under the IS 2062 scheme means the Bureau of Indian Standards has assessed the manufacturer's production process, product quality, and testing infrastructure against the requirements of IS 2062. The manufacturer holds a BIS license — identified by a CM/L number — and is authorized to apply the ISI mark to conforming products.
This involves:
- Factory audit by BIS officials
- Product testing at BIS-recognized or NABL-accredited laboratories
- Ongoing surveillance visits and market sample testing
- License renewal (typically every 1–2 years)
When a mill produces ISI-marked IS 2062 plates, the MTC must carry the BIS license number (CM/L number). This number is traceable to the BIS product certification portal, where the license status, scope, and validity can be verified.
When Each Document Is Required
For commercial and private construction projects, an IS 2062-compliant MTC from any reputable mill is generally sufficient. The buyer is relying on the mill's test data. There is no government body requiring ISI marking for a private industrial warehouse or a private residential structure.
For government infrastructure projects, the requirement changes. CPWD specifications, NHAI project contracts, Indian Railways procurement standards, and many state PWD specifications explicitly require ISI-marked material. The project engineer is not asking whether the steel meets IS 2062 — they are asking whether it carries the ISI mark, which implies BIS certification.
The distinction: IS 2062-compliant material and IS 2062-certified material are not the same thing.
What the MTC Must Show for ISI-Marked Material
If a mill claims its material is ISI-marked under the BIS scheme, the MTC must include:
- The BIS license number in the format CM/L-XXXXXXX
- Reference to the BIS certification scheme
- The ISI mark either embossed on the material or clearly indicated on the MTC
Auditors and TPI inspectors check three things:
- Is the ISI mark physically present on the material (or on a label for plates)?
- Does the CM/L number on the MTC match what is on record at the BIS portal?
- Is the BIS license currently active and within its validity period?
If the CM/L number on the MTC resolves to an expired or cancelled license on the BIS portal, the material fails — regardless of whether the physical ISI mark is present.
What Triggers NCRs in Practice
Based on typical audit patterns on government structural projects, the following situations generate non-conformance reports:
MTC shows IS 2062 compliance, no ISI mark on material. Project spec requires ISI-marked material. NCR raised. The fabricator must source replacement material or obtain a concession from the project owner.
ISI mark present on material, CM/L number missing from MTC. Inspector cannot verify BIS license. Material quarantined pending fresh MTC with complete information.
CM/L number on MTC does not match active BIS license. This happens when mills continue marking after license expiry or when distributors attach the wrong MTC to material from a different heat or mill. Material rejected.
Grade not specified on MTC. IS 2062 has multiple grades (E250, E300, E350, E410, E450). An MTC that says only "IS 2062" without specifying grade is incomplete. The inspector cannot verify grade conformance.
Building a Document Review Step
Structural fabricators who supply to government projects need a document review step that checks for all of the above before the material reaches the shop floor — not at the time of delivery to the project site.
The checklist at goods inward should include:
- MTC present with heat number that matches the material tag
- Grade explicitly stated (e.g., E250 BR)
- ISI mark present on material or label (for plate stock)
- CM/L number present on MTC
- BIS license verified as active on the BIS portal
- Lab report from NABL-accredited lab attached (for government projects requiring additional evidence)
A one-page verification form attached to each MTC at goods inward, signed by the quality engineer, creates the audit trail that TPI inspectors and project QA teams need.