If you have landed here after searching for IS 3455 or IS 919, you probably want two things: what the standard actually covers, and what it means when you are specifying or accepting plain gauges. This page answers both, and flags an edition problem that trips up a lot of Indian shops.
One sets the target. The other governs the instrument you judge it with. You need both, and they are not interchangeable.
The current edition of IS 3455 is still IS 3455 : 1971 (First Revision). BIS has not issued a later revision. It was reaffirmed in 2020, which keeps it the active Indian Standard for gauging practice on plain workpieces. A search for "IS 3455 latest edition" is looking for that 1971 text, not a 2020 rewrite — 2020 is the reaffirmation year.
Do not mix it up with IS 3455 (Part 1) : 1985, a separate part covering indicating instruments rather than fixed limit gauges. Both parts are current.
Queries for "ISO 3455 standards" often land here by accident. ISO 3455:2021 is a hydrometry document — calibration of current-meters in straight open tanks. It has nothing to do with plain gauges.
The ISO document that does pair with this page is ISO 286. IS 919 (Part 1) : 2014 is identical to ISO 286-1:2010, and IS 919 (Part 2) : 2014 is identical to ISO 286-2:2010. IS 3455 itself has no ISO equivalent; it is an Indian gauging-practice standard.
The base document is IS 3455 : 1971, "Gauging Practice for Plain Workpieces" (First Revision), issued under BIS technical committee PGD 25 (Engineering Metrology). It remains active and was reaffirmed in 2020. The commonly circulated print is the Fifth Reprint of November 1996, which incorporates Amendments 1 to 4.
Its stated scope is narrower than people assume:
"Lays down the gauging practice for inspection of plain workpieces with dimensions less than 500 mm. This standard also gives the manufacturing tolerances and the permissible wear limit of the gauges."
Two things follow from that sentence. First, the standard stops at 500 mm — above that you are outside its scope and need another basis of agreement with your customer. Second, it is not only about how to gauge; it is also the document that tells a gauge maker how much tolerance the gauge may carry and how far it may legitimately wear.
There is also IS 3455 (Part 1) : 1985, "Inspection of Plain Workpieces with Indicating Measuring Instruments" (also PGD 25, reaffirmed 2020), which covers the comparator and dial-instrument route rather than fixed limit gauges.
Clause 2.1 is worth quoting when a customer disputes a result:
"Unless specified to the contrary, inspection by limit gauges is recognized as the acceptable method for dimensional conformity to the specification of plain workpieces."
The standard then sets out the manufacturer-versus-purchaser gauging procedure that exists specifically to stop supplier and customer arguing from two different gauges. It also notes that the inspector's gauge tolerance zones should be placed so that the inspector does not reject workpieces that are genuinely within the specified limits — a detail that matters when incoming inspection keeps rejecting parts the supplier says are good.
Clause 3.1 fixes the reference temperature for all industrial length measurement at 20 °C. That is the temperature at which the workpiece and the gauge dimensions are defined, and at which inspection should normally be carried out.
The practical relief is in 3.2: if the workpiece and the gauge share the same coefficient of linear expansion — steel part, steel gauge — the checking temperature may deviate from 20 °C without harming the result, provided both are at the same temperature. That is why a gauge brought in from an air-conditioned room should be left to settle next to the parts before use.
Clause 3.3 removes that relief when the coefficients differ, for example a steel workpiece checked with a carbide gauge. If you have moved to carbide members for wear life, temperature control stops being optional.
Section 4 is titled "Limits of Size for Gauging (Taylor Principle)". The standard's interpretation is:
In plain terms: the GO gauge checks the assembly condition over the full length, the NO GO gauge checks size at a point. That is why a GO plug is full-form and full-length while a NO GO member is short and effectively two-point. A workshop that grinds a worn GO plug shorter has quietly stopped testing what the standard says it should test.
Clause 4.1.1 draws out the consequence: if the size is everywhere at the GO limit, the hole or shaft must be perfectly round and straight. Clause 4.2 states the flip side — subject to that, departures from roundness and straightness may reach the full value of the diametral tolerance. The standard illustrates these extreme permitted form errors in Figures 1 and 2.
The standard is also realistic about it: strict application of the Taylor principle "is not always strictly compulsory or comes up against difficulties in conveniently using gauges", and permitted deviations are set out in the standard's own clauses. If you need to depart from full-form GO gauging on a long bore, do it deliberately and record the agreement — do not let it happen by default because a gauge was easier to make that way.
Section 10, "Manufacturing Tolerances and Permissible Wear of Gauges", is the part most buyers never read and most disputes come back to. It defines a symbol set, including:
The logic that these symbols encode is the useful part. A reasonable working life for a GO gauge is created in two ways at once: the tolerance zone of a new GO gauge is set inside the workpiece tolerance by the amount Z, and the GO gauge is then allowed to wear outside the GO limit of the workpiece by the amount Y. A new GO gauge is therefore deliberately not made to the exact workpiece limit — it starts tight and is permitted to drift.
For NO GO gauges, the standard places the tolerance zone symmetrically about the NO GO limit for nominal sizes up to and including 160 mm. Above 180 mm it shifts the zone inside the workpiece tolerance by a safety amount that compensates for the measuring uncertainty of large gauges.
Three practical consequences:
The numeric values of H, Y and Z are tabulated in the standard against nominal size and tolerance grade. We have deliberately not reproduced those tables here — buy IS 3455 from BIS if you need to work from them, or send us the drawing and we will apply them for your sizes.
This is where a lot of Indian drawings are out of date. IS 3455:1971 internally references IS 919-1963, "Recommendations for limits and fits for engineering". IS 919 has been revised several times since:
Two things to take from this. First, if your drawing or quality plan still cites "IS 919 : 1993" or "IS 919 : 1963", it is citing a superseded edition — the tolerance intent is largely carried through, but the reference is wrong and an auditor may pick it up. Second, Part 2 is the one with the tables. If someone asks for "the IS 919 tolerance chart" for an H7 bore or a g6 shaft, Part 2 : 2014 is the document.
Because Part 1 : 2014 is identical to ISO 286-1:2010, an H7/g6 call-out means the same thing whether the drawing cites the IS or the ISO number. That is useful when you are supplying an export customer working to ISO and an Indian customer working to IS from the same part drawing.
When we quote a plain gauge, these are the questions the two standards force:
We do not host, and cannot email, an IS 3455 or IS 919 PDF. Those files are BIS copyright. Buy them from the BIS e-Sale portal: IS 3455 : 1971 for gauging practice and the H/Y/Z tables, and IS 919 (Part 2) : 2014 for the limits-and-fits charts. Free copies circulating as "IS 3455 standard PDF" or "IS 3455 of 1971 PDF" are unofficial and often incomplete — do not work from them.
IS 3455 (Part 1) : 1985 and IS 919 (Part 1) : 2014 are on the same portal. If you would rather not work through the tables yourself, send us the drawing. We manufacture plain plug, ring, and snap gauges to IS 3455 gauge tolerances at our Coimbatore works, and the calibration certificate will state the measured size, the gauge tolerance applied, and the wear limit so your recall programme has something to measure against.
The current edition is still IS 3455 : 1971 (First Revision). BIS has not issued a later revision; it was reaffirmed in 2020, which keeps the 1971 text active. A search for the latest edition is looking for that document — 2020 is the reaffirmation year, not a new revision.
No. ISO 3455:2021 is a hydrometry standard — calibration of current-meters in straight open tanks — and has nothing to do with gauges. IS 3455 has no ISO equivalent; it is an Indian gauging-practice standard. The ISO document that does pair with it is ISO 286, which IS 919 (Parts 1 and 2) : 2014 adopts identically.
Its stated scope is inspection of plain workpieces with dimensions less than 500 mm. Above 500 mm you are outside the standard, so the gauge tolerance and wear allowance need a separately agreed basis with your customer.
It is the rule that a GO gauge checks the assembly condition over the full length while a NO GO gauge checks size at a point. For a hole, the largest perfect cylinder that can be inscribed so it just contacts the high points must not be smaller than the GO limit, and no diameter may exceed the NO GO limit; shafts mirror this. It is why a GO plug is full-form and full-length while a NO GO member is short.
They are the gauge tolerance and wear framework in Section 10. H is the tolerance on a cylindrical plug or bar gauge. Y is how far outside the GO workpiece limit a gauge is permitted to wear. Z is how far inside the workpiece limit a new GO gauge's tolerance zone is set. A new GO gauge is therefore deliberately not made to the exact part limit — it starts inside by Z and may wear outside by Y.
From the BIS e-Sale portal. We do not host or email it: the file is BIS copyright. Copies circulating as a free IS 3455 PDF are unofficial and often incomplete, so do not work from them.
IS 919 (Part 1) : 2014 and IS 919 (Part 2) : 2014. Part 1 is identical to ISO 286-1:2010, the basis of tolerances, deviations and fits; Part 2 is identical to ISO 286-2:2010, the tables of standard tolerance grades and limit deviations. Drawings still citing IS 919 : 1993 or : 1963 are citing superseded editions.
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