MFDS Tightens ZLD TOC Verification Rules

The timing of the underlying case is not specified in the source input, but the regulatory update itself is clear: on June 24, 2026, South Korea’s MFDS revised its ZLD system certification implementation rules and added a new requirement for TOC removal verification. For companies involved in wastewater reuse equipment, laboratory testing, certification preparation, and cross-border compliance documents, this is worth close attention because it changes which test reports are acceptable for ZLD certification filings in Korea.

What the revised rule now requires

According to the provided information, MFDS updated the ZLD System Certification Implementation Rules (2026 Revision) on June 24, 2026 and added Article 4.2.7.

Under this new provision, all applicants seeking ZLD certification for wastewater reuse equipment must submit TOC removal rate verification reports issued by KOLAS-authorized laboratories that are under CNAS mutual recognition.

The requirement applies to wastewater reuse equipment including evaporative crystallizers, membrane distillation units, and online TOC monitoring modules. The test method must comply with KS IEC 62321-10:2026.

The input also states that reports previously issued by Chinese CMA laboratories are no longer accepted for this purpose.

Where the practical impact is likely to appear

Certification preparation for equipment suppliers

From an industry perspective, manufacturers and exporters of wastewater reuse equipment may be affected first because the rule directly changes the documentation basis for ZLD certification applications in Korea. The impact is likely to appear in test planning, report selection, and submission readiness rather than in product description alone.

Laboratory selection and compliance coordination

Testing service providers and compliance teams may need to pay closer attention to laboratory qualification pathways. Analysis shows that the key issue is not only whether a TOC report exists, but whether the report is issued by a laboratory matching the KOLAS authorization and CNAS mutual recognition condition described in the rule, while also using the specified KS IEC 62321-10:2026 method.

Procurement and project delivery schedules

For buyers, integrators, and project delivery teams, the rule may influence document review timelines and acceptance planning. Observably, if a report format or issuing laboratory no longer meets the filing requirement, certification-related delivery steps could require resubmission or additional coordination.

What companies should monitor now

Check whether existing TOC reports remain usable

Companies preparing ZLD certification submissions should review whether current TOC removal verification reports were issued under the laboratory route now required by MFDS. This is especially relevant where earlier files relied on Chinese CMA laboratory reports.

Confirm method alignment with KS IEC 62321-10:2026

What deserves closer attention is the method requirement itself. Even where a laboratory appears acceptable, applicants still need to confirm that the testing method in the report is aligned with KS IEC 62321-10:2026 as stated in the revised rule.

Reassess supplier and service-provider documentation

For equipment makers and service providers, it is practical to review quotations, testing scopes, certification schedules, and document checklists with laboratories and downstream customers. The main concern is whether documentation can support application timing without avoidable rework.

Watch for further official clarification

The current input confirms the new acceptance rule, but companies should continue monitoring whether additional official wording, implementation notes, or operational guidance emerge around application review and document interpretation.

How this update is best understood at this stage

Analysis shows that this is not just a technical wording change in a testing clause. It signals a stricter approach to traceability and report acceptability in the Korean ZLD certification process, particularly for TOC removal verification. At the same time, based only on the provided information, it would be premature to treat this as a broader market-wide outcome beyond certification documentation and testing compliance.

It is more appropriate to understand this as a concrete compliance change with possible wider implications for testing arrangements, supplier coordination, and certification lead times. Whether it develops into a longer-term shift in laboratory selection patterns still requires continued observation.

Why the market should keep following it

At present, the clearest significance of this update is that acceptable evidence for ZLD certification in Korea has become more narrowly defined for TOC removal rate verification. For affected businesses, the immediate issue is operational: which laboratory can issue a usable report, under which method, and for which equipment categories.

A balanced reading is that this is already a real short-term compliance change, while its broader long-term effect on cross-border testing and certification workflows still needs to be tracked through further implementation practice.

Basis of this article and points for further verification

This article is generated from the user-provided news title, event timing note, and event summary. The specific official source link was not provided in the input, so further verification is still necessary.

For this type of development, relevant source categories typically include official regulatory notices, standard documents, accreditation system information, industry association updates, company compliance notices, and reporting by authoritative trade media. Further follow-up should focus on any additional MFDS clarification, implementation interpretation, and related guidance concerning laboratory qualification and report acceptance in practice.