IS 4985 defines every genuine PVC pressure pipe sold in India. Here is exactly what the standard requires, what the print on the pipe must say, and how to catch a fake in thirty seconds.
Counterfeit PVC pipe is a real market problem in India. Uncertified stock is typically 20 to 30 percent cheaper, looks identical on the shelf, and fails inside three to five years — usually after the wall or floor is already closed. This guide gives you the exact checks to verify IS 4985 compliance and catch a fake before it reaches the trench.
What IS 4985 Actually Covers
IS 4985 is the Bureau of Indian Standards specification for unplasticised PVC pipes used for potable water supply. It defines:
Material grade — K-value and impact modifier limits.
Wall thickness — minimum for every nominal diameter and pressure class.
Pressure classes — Class 1 (2.5 kgf/cm2) through Class 6 (12.5 kgf/cm2).
Hydrostatic test — pipes must survive one hour at four times working pressure.
Marking requirements — what must be printed on the pipe every metre.
Falsely selling non-conforming pipe as IS 4985 is an offence under the BIS Act 2016.
What Must Be Printed on Every Genuine Pipe
IS 4985 pipes carry a mandatory print string every metre. All eight elements must be present:
| # | Element | Example |
|---|---|---|
| 1 | ISI Mark logo | Standard ISI symbol |
| 2 | IS Number | IS 4985 |
| 3 | BIS Licence Number | CM/L-1234567 |
| 4 | Manufacturer name | Jindal PVC Pipes |
| 5 | Nominal size and OD | 90 mm OD |
| 6 | Pressure class | Class 3 |
| 7 | Batch or lot number | B26041 |
| 8 | Month and year of manufacture | APR 2026 |
Verify the BIS Licence in Thirty Seconds
Every BIS licence number (CM/L format) is publicly searchable:
1. Install the BIS Care mobile app (Android and iOS).
2. Open Verify Licence Details and paste the CM/L number from the pipe.
3. The app returns the licensee name, product, standard and expiry. Match the name against the manufacturer printed on the pipe.
If any element does not match, the pipe is either counterfeit or the licence has been suspended. Reject the consignment.
Physical Checks That Catch Most Fakes
Weight per length. Compare the actual weight to the IS 4985 nominal weight for that size and class — fakes are typically 8 to 15 percent underweight.
Wall thickness. Measure with a caliper at three points around the circumference. A thin wall means less material and lower pressure rating.
Colour. Genuine IS 4985 pipe is a consistent grey to cream. Yellowish, patchy or foul-smelling pipe usually contains reprocessed scrap.
End cut. Should be clean, square and free of burr. Ragged cuts indicate rushed manufacturing.
Impact test. Drop a small offcut from 1 metre onto concrete. Genuine pipe rings; brittle counterfeit shatters.
The BIS Test Certificate
For any procurement above one truckload, insist on the BIS Test Certificate or the manufacturer's third-party test report for the specific batch. Genuine manufacturers issue this on request without hesitation.
Why This Matters
A PVC pipe is a 25 to 50 year investment. Underspec pipe fails at joints, cracks under summer heat and leaks silently inside walls. The saving on an uncertified pipe is trivial compared to the cost of a single wall break-open. IS 4985 verification takes two minutes and eliminates the entire category of risk.
Frequently Asked Questions
What does IS 4985 stand for?
IS 4985 is the Bureau of Indian Standards specification for unplasticised PVC pipes used for potable water supply. It defines material, wall thickness, pressure class, hydrostatic testing and marking requirements.
How do I verify the ISI mark on a PVC pipe?
Read the BIS Licence Number (CM/L format) printed on the pipe and verify it in the BIS Care mobile app. The licensee name in the app must match the manufacturer printed on the pipe.
What information should be printed on an ISI marked PVC pipe?
ISI mark, IS 4985 number, BIS licence number (CM/L), manufacturer name, nominal size, pressure class, batch number and month-year of manufacture — printed every metre.
Are Jindal PVC pipes IS 4985 certified?
Yes. Every Jindal PVC pressure pipe is manufactured under valid BIS licence to IS 4985 and carries the ISI mark with the complete print string.
Reviewed by
Sahil Jindal
Managing Director, Jindal Composite Tubes Pvt Ltd
3rd-generation pipe manufacturer with 25+ years of hands-on experience in PVC, CPVC and UPVC pipe engineering, ISI/BIS compliance and India-wide plumbing distribution.