The MS 2564 revision: why Malaysia's CEMS certification standard is becoming MS 2564-1

A standard for industry, regulators and equipment buyers, drawn from MS 2564:2014 and the standards-committee work behind its revision.

We’ve written before about MS 1596 — Malaysia’s stack-test standard. There’s a second Malaysian Standard behind CEMS compliance, and it’s also under revision: MS 2564. Same working group, same moment for a why-and-direction piece — and the same disclosure line applies:

Status — July 2026: MS 2564 is under revision. This article explains what the current 2014 edition covers, why it’s being revised, and the direction that’s already visible from its own text and from the published international standards it points to. It does not disclose draft content or pre-empt the committee. The specifics will follow here once the Department of Standards Malaysia (JSM) publishes the new edition.

MS 1596 measures the stack. MS 2564 proves the instrument.

It’s easy to conflate the two, so it’s worth being precise. MS 1596 is the Standard Reference Method (SRM) — the manual stack test a QAL2 checks your CEMS against. MS 2564 sits earlier in the chain: it’s Malaysia’s standard for performance criteria and test procedures for continuous emission monitoring systems — the requirements a CEMS design has to satisfy, and how a certification body tests it, before it ever reaches a Malaysian stack. In the language of EN 14181, MS 2564 sits behind QAL1 — the certification stage, owned by the manufacturer, that happens before purchase.

What MS 2564 covers today

The current edition, MS 2564:2014, was developed — like MS 1596’s revision — by the Working Group on Stationary Source Emissions, under the Industry Standards Committee on Environmental Management. Its scope is broad: performance criteria, test procedures and general requirements for CEMS. The standard’s own list of covered determinands — “including, but not restricted to” — runs to SO₂, NOₓ, CO and CO₂, HCl, HF, CH₄, mercury, VOCs (as TOC), O₂, water vapour, flow rate, and particulate matter, across incineration, combustion, solvent-using and gas-turbine processes.

Certification under MS 2564 runs in three phases:

• Laboratory testing — performance characteristics measured under highly controlled conditions: linearity, cross-sensitivity, response time, detection limit, and more.
• Field testing — at least three months, on a process representative of the intended application.
• Surveillance — an ongoing audit of the manufacturer’s production and design-control processes, so a certified model doesn’t quietly degrade after certification.

One part of MS 2564 deserves more attention than it usually gets, because it isn’t reflected anywhere else on this site yet: particulate monitors aren’t all held to the same standard.

The practical takeaway: if your facility falls under large combustion plant or incineration rules, “a dust monitor” isn’t enough — you need a Class 1 instrument, held to the full QAL1/QAL3 bar. That’s also the standard buying a MCERTS- or TÜV-certified analyser already gets you, which is why this classification rarely surfaces as a buying decision in practice — but it’s the reasoning underneath it.

Where MS 2564 already points internationally

Here’s the detail that sets up the revision, and it’s already visible in the 2014 text: MS 2564 was never a standalone Malaysian invention. Its own normative references list EN 15267-2 and EN 15267-3 — the European certification series for automated measuring systems — alongside MS ISO 14956, the Malaysian adoption of the ISO standard for evaluating whether a measurement method meets a required uncertainty. The standard’s Foreword is explicit that certification itself runs on EN 15267-1, and that test laboratories need accredited procedures complying with EN 15267-3 and MS ISO/IEC 17025.

Because those references are undated in the 2014 text — under JSM’s own drafting convention, an undated reference means “the latest edition applies” — MS 2564 has, in a sense, always been tracking whatever the current EN 15267 and ISO 14956 editions say. The revision’s job is largely to make that tracking explicit again for the editions now in force.

The rename itself is a useful signal on its own. Moving from an unnumbered “MS 2564” to a part-numbered “MS 2564-1” mirrors the shape of the EN 15267 series it already leans on (Parts 1, 2 and 3) — suggesting the Malaysian standard is being structured to grow the same way, rather than staying a single monolithic document.

How a Malaysian Standard actually gets made

We covered this in detail when MS 1596’s revision went through the same process, so the short version here: JSM develops a Malaysian Standard through an eight-stage consensus process — proposal, committee drafting, public comment, acceptance, verification, and finally the Minister’s declaration that publishes it. A draft in committee is exactly that, a draft; its content can still move at public comment. The same working group is doing this work for MS 2564 as for MS 1596, on the same timeline logic.

Why it matters to you

If you’re buying a CEMS today, the practical guidance doesn’t wait for the revision. A current MCERTS or TÜV QAL1 certificate — which is what we already tell buyers to demand in QAL1 and certification — is issued under schemes built on the same EN 15267 series MS 2564 already references. Buying to that bar means you’re already buying to where MS 2564 is heading, not just where it’s been. The revision mostly formalises, at the national level, what a properly certified instrument already satisfies internationally.

For testers and regulators, a renamed, re-anchored MS 2564-1 closes the same kind of gap MS 1596’s revision closes for stack testing: less daylight between the Malaysian standard and the international editions it was always meant to track.

Choosing equipment and want the certification checked properly before you commit? Talk to us — our CEMS installation service verifies QAL1 certification and instrument fit before anything goes on your stack, and we sit on the working group revising both MS 1596 and MS 2564.

This article is general guidance, not legal advice, and discusses a standard that is under revision; nothing here represents the final content of the new edition. For obligations specific to your facility, refer to the current Environmental Quality (Clean Air) Regulations 2014, the EQA 1974, the DOE CEMS Guidelines, and the current edition of MS 2564, or speak with us directly.