• ByRouging Solutions Editorial Team  ·  1 September 2026

ASTM A380 Explained: A Guide to the 2025 Practice

ASTM A380 is the document that tells you how to clean, descale, pickle and passivate stainless steel. It covers loose parts, built assemblies and whole systems already erected on site. It is a practice rather than a specification. That means it recommends methods. It does not set a mark you can certify against.

The current version is ASTM A380/A380M-25. It replaced the 2017 version, and the title changed along with it. Pickling is now named in the title, next to cleaning, descaling and passivation.

That matters more than it sounds. If your cleaning procedure still cites the 2017 version, look at the acceptance-test clause numbers in it. Those no longer match the edition an auditor is likely to be holding.

What Is ASTM A380?

It is the ASTM practice for cleaning stainless steel surfaces so they resist corrosion. Its full name today is Standard Practice for Cleaning, Descaling, Pickling, and Passivation of Stainless Steel Parts, Equipment, and Systems (ASTM A380/A380M-25).

The scope says when to reach for it. Use it when oxide scale, rust, grease, oil, metal chips or dirt sit on the surface. Any of those can harm the metal, the hygiene of the surface, or the fluid running through the system.

One line in the scope decides a lot. Clause 1.2 says A380 does not cover cleaning of equipment or systems that have been in service. Scale removal at the steel mill is outside it too.

The dividing line is service rather than location. A system erected on site but not yet running is inside the scope. The same system two years into production is not.

So a reactor that has run for six years and grown a rusty film sits outside what A380 says it covers. Many of A380's methods still help there. But the job has a different name, and our guide to identifying rouge contamination covers what that film looks like.

A380 sits in Book of Standards Volume 01.03, under committee A01 and subcommittee A01.14. The 2025 version runs to 14 pages.

How Is ASTM A380 Different From ASTM A967?

One recommends, the other requires. A380 describes the methods and the care the work needs. ASTM A967/A967M-25 defines the chemical passivation treatments. It also lists seven tests, Practice A through Practice G. A batch passes or fails the tests your specification names.

A967 points back at A380 in its own scope. It says the mechanical and chemical treatments of stainless steel surfaces "are discussed more thoroughly in Practice A380/A380M". The two are written to be read together.

The purchase specs we see for pharma and food equipment usually name both. If yours names only A967, the cleaning and descaling steps are left open. Our guide to the ASTM A967 passivation standard covers the specification side in detail.

What Changed in the 2025 Revision?

Four things you can see without opening the paid document. Three are wording. One will break a cross-reference in your own procedure.

Pickling is in the title. The title of the 2017 version read Cleaning, Descaling, and Passivation. Pickling dissolves a little of the metal itself, usually with a nitric and hydrofluoric acid mix. It was already inside the document, and now it is on the cover as well. Our pickling and passivation comparison explains why the two get mixed up.

The word "new" is gone. The 2017 scope covered "new stainless steel parts", and the 2025 scope drops the word "new". Clause 1.2 still rules out in-service cleaning, so the change looks like tidier wording rather than a wider scope.

"Free iron" became "contaminant iron". The 2025 scopes of both A380 and A967 use the newer phrase. A380's published abstract still uses the older one in the name of its free iron test.

The clause numbers moved. In 2017, the scope pointed to 7.2.5 and 7.3.4 for the acceptance tests. In 2025 those sit at 8.2.5 and 8.3.4. The annex references A1.7 and A2.11 did not move.

What the Practice Asks You to Do

Work in a set order, and plan the cleaning before you build. The published abstract lays the sequence out plainly.

1. Design it so it can be cleaned. Avoid pockets where dirt or cleaning fluid can sit. Give the fluid a path to flow through and drain.
2. Preclean the material before anything else touches it.
3. Take the scale off, by chemical descaling, acid pickling or mechanical descaling. We do the chemical and mechanical descaling on site, at the point a system is erected.
4. Degrease and clean. The abstract lists immersion, swabbing and spraying with alkaline, emulsion, chelate, acid, solvent or detergent cleaners. Vapor degreasing, ultrasonics, steam and high pressure water jetting are all named too.
5. Give welds their own attention. Welds and weld joint areas carry separate advice, and so do critical applications and systems already erected.
6. Rinse, then protect the surface so it does not pick up dirt again on the way to service.
7. Passivate where your purchase specification calls for it, then check the result.

Step one is the easiest to skip. By the time anyone opens A380, the vessel is usually already welded.

Step three has one route we do not offer, and that is pickling. We do descaling, cleaning, derouging, passivation, polishing and inspection. Pickling eats into the metal itself, and a shop built for that will do it better than we would.

Which Cleanness Checks Does ASTM A380 Name?

Eleven of them, in two groups: seven routine checks and four precision methods. All eleven sit in A380, and they judge how clean the surface is. Two are named identically in A967, the high humidity and copper sulfate tests, and the ferroxyl test is A967's Practice E under another name. That is where the two standards touch.

A380's published abstract gives seven ways to judge cleanness:

• Visual inspection
• Wipe tests
• Residual pattern
• The water break test
• A free iron test, such as water-wetting or drying
• The high humidity test
• The copper sulfate test

The same abstract names four precision methods for finer work. Those are the solvent ring test, black light inspection, the atomizer test and the ferroxyl test. Several of the eleven look for iron. The four precision methods pick up what an eye misses, whether that is iron or organic residue.

The ferroxyl test is the one we get asked about most often for embedded iron. Euro Inox calls the ferroxyl test sensitive enough to find either free iron or iron oxide. That guide then sends readers to "ASTM A380 section 7.3.4" for the recipe (Pickling and Passivating Stainless Steel, 2007).

Whichever edition that pointer was written against, it does not match the current one. The clause numbers moved in 2025. A recipe cited by an old number is worth correcting before anyone asks. What each test actually proves is covered in passivation testing methods.

Where Does ASTM A380 Show Up in an Audit?

In your cleaning procedure, and in the records behind it. US GMP asks for written procedures. Those procedures must carry "a description in sufficient detail of the methods, equipment, and materials used in cleaning and maintenance operations" (21 CFR 211.67). The same rule says records shall be kept of maintenance, cleaning, sanitizing and inspection.

A380 is where that detail usually comes from. What the finished record has to show is a subject of its own, set out in passivation documentation. In our experience an inspector rarely asks whether you own the standard, and asks instead about the method, the date and the result.

This lands hardest on Indian plants that export. India shipped ₹2.74 lakh crore of pharma exports in FY26, up from ₹2.59 lakh crore in FY25. It also has more FDA approved plants than any country except the US (IBEF).

Someone from outside the company comes and asks for the records. That is why our passivation work goes out with the documents that back it up.

What Do Plants Get Wrong About A380?

Five things, and most are cheap to fix. Three are about the document itself: what it awards, which version you are citing, and what it covers. Two are about the work: skipping the descaling step, and confusing pickling with passivation.

• Asking for an A380 certificate. Nobody is certified to A380, because it is a practice. A vendor works to it and records what they did. That is all.
• Citing A380 with no year. A 2019 procedure that says only "as per ASTM A380" gives an auditor no way to tell which edition it was written against. If 7.2.5 or 7.3.4 sits beside it, those numbers are now 8.2.5 and 8.3.4.
• Assuming it covers in-service cleaning. By its own clause 1.2 it does not, so that work gets planned as derouging or descaling.
• Skipping descaling because the vessel looks clean. Scale is not always dark, and passivating over it treats the scale rather than the steel.
• Treating pickling and passivation as the same step. Pickling removes metal, and passivation does not.

The following scenario is fictional. It is an illustrative example, not a specific project or client.

A formulation plant near Ahmedabad passes its internal check, then fails a customer audit on one line. The SOP cited section 7.3.4 for its iron test. The auditor held the 2025 practice, and the numbers in the SOP did not match it. The test itself had been run properly for years.

Paperwork is where a lot of audit findings begin. For the ones that start on the metal instead, read common passivation failures.

Start With the Version Number

The one thing to remember: A380 sets out how the work is done, and A967 says whether it passed. You need both named in your procedure.

On Monday morning, open your cleaning SOP and search it for "A380". If it shows a year before 2025, or no year at all, that line needs an update. Check any clause numbers next to it while you are there.

If you want a second pair of eyes on the procedure before an audit, talk to our team. We work to A380 and A967 on site, and we hand over the records with the job.

Frequently Asked Questions