Fashion Brand ZDHC Requirements for Dyeing Mills 2026
Table of contents
Quick summary
- Industry practice: international fashion brands typically expect dyeing mills to use chemicals that fit the ZDHC MRSL v3.1 and to self-declare and test their wastewater under the ZDHC Wastewater Guidelines. The exact requirements and documents are set by each brand and by each contract or order.
- Use the right terms: Level 1–3 (ChemCheck on Gateway) describes MRSL conformance of a chemical product, not of a mill. Wastewater Guidelines V2 take effect on 01 December 2026.
- ZDHC MRSL v3.1 Conformance Level 1 (9 Flagship Products): Loc Thien holds official Level 1 documentation for 9 flagship products: TÜV SÜD Level 1 Certificates (
#ZDHC1 127736 0001–0004: NaOH, H₂O₂, Na₂SO₄, Na₂CO₃) and TÜV Rheinland Vietnam Level 1 CSR & Analytical Test Reports (#248162921-01–05: H₂SO₄, FeCl₂ 30%, HCl, Javel/NaOCl, PAC 31%).
What do fashion brands usually require from dyeing mills?
ZDHC (Zero Discharge of Hazardous Chemicals) is a collaborative programme of fashion brands that aims to remove hazardous chemicals from the textile supply chain. It is a commercial requirement, not Vietnamese law: mills must still meet national wastewater standards (QCVN), and ZDHC itself states that its guidelines do not replace local regulation.
Industry practice falls into two groups:
- Input chemicals. The mill keeps a chemical inventory list (CIL), checks it against ZDHC MRSL v3.1 and reports it through InCheck. For some chemical groups a brand may want to see the product’s Level on ZDHC Gateway; other brands accept different documents — it depends on the brand.
- Wastewater. The mill self-declares and tests wastewater under the ZDHC Wastewater Guidelines and publishes results as a ClearStream report. The current V2.2 describes two test cycles a year (October and April); actual frequency and deadlines follow each brand’s request.
This article does not quote brand-specific figures: thresholds, schedules and targets sit in each brand’s supplier rules or contract. The safest step is to ask the brand’s purchasing/compliance team for the written requirement that applies to the order in hand.
Five “ZDHC papers” that get confused
| Document | Whose | What it tells you | What it does not tell you |
|---|---|---|---|
| MRSL v3.1 | ZDHC | List of substances banned from intentional use in chemical formulations, including wastewater-treatment chemicals | Not a paper for one specific product |
| Conformance Level 1/2/3 | A chemical product, issued by a ZDHC Approved MRSL Certifier | L1: SDS review + analytical testing + screening. L2: L1 + on-site assessment of the management system. L3: on-site assessment of chemical hazard assessment capability | Not a mill level. legacy “Registered” tier has been dropped |
| ChemCheck | Generated from Gateway for a product | Product “passport”: Level and MRSL version | A stand-alone test report is not a ChemCheck |
| InCheck | The mill | Inventory of input chemicals (Performance: self-declared; Verified: independently verified) | Not a supplier document |
| ClearStream | The mill | Wastewater results for each cycle | Says nothing about input chemicals |
When a supplier says “ZDHC MRSL v3.1 Level 1 conformant”, ask: is it a Level/ChemCheck you can look up on Gateway, or a laboratory test report? They prove different things.
Figure: On-site chemical dosing, storage tank operation, and batch COA inspection — Source: Loc Thien Chemical.
2026 milestone: Wastewater and Sludge Guidelines V2
According to ZDHC, Version 2 of the Wastewater and Sludge Guidelines takes effect on 01 December 2026, with four requirements: wastewater testing, sludge testing with the sludge disposal route, root cause analysis/corrective action plan (RCA/CAP), and fibre fragmentation. Parameter limits are in the official Guidelines. Suggestion: schedule sampling and talk to your laboratory before this date.
See What is ZDHC and the ZDHC implementation checklist for dyeing mills.
Documents a mill should prepare (general suggestion)
| Document | Prepared/kept by | Used for | Note |
|---|---|---|---|
| Chemical inventory list (CIL) | Mill | List chemicals in use, check against MRSL v3.1 | Update when supplier or recipe changes |
| InCheck | Mill | Chemical inventory report | The brand decides Performance or Verified |
| Current SDS + batch COA | Supplier | Identity and quality of each batch | Name/concentration must match the CIL |
| ChemCheck/Level (if the brand requires it) | Certifier → Gateway | MRSL conformance of the product | Look it up on Gateway; if absent, do not claim it |
| Supplier’s MRSL test report | Laboratory | Substance groups tested, methods, date | Read the scope; it does not replace a Level |
| ClearStream report | Mill | Wastewater results per cycle | Tested at a ZDHC-accepted laboratory |
| Record of ETP chemical changes | Mill | Jar tests, batch COA before/after the change | Keep with the CIL |
This is general guidance. Mandatory documents, minimum Level and submission frequency follow the contract/rules of each brand for each order.
ZDHC documentation for Loc Thien FeCl₂
Loc Thien’s FeCl₂ (labelled 30%) has a ZDHC MRSL v3.1 test report from TUV Rheinland Vietnam Co., Ltd., no. #248162921-02a, dated 23 October 2024, using Smart testing (screening by substance group) for 5 groups: chlorobenzenes/chlorotoluenes, chlorophenols, phthalates, glycols/glycol ethers and sodium salts of perboric acid. The report names the sample “Ferrous Chloride (Liquid)” and states no concentration.
Alongside Analytical Test Report #248162921-02a, Loc Thien’s FeCl₂ holds a Conformance Summary Report (CSR #248162921-02, dated 22 October 2024) confirming ZDHC MRSL Version 3.1 Conformance Level 1, within Loc Thien’s portfolio of 9 flagship products achieving Level 1 (NaOH, H₂O₂, Na₂SO₄, Na₂CO₃ certified by TÜV SÜD #ZDHC1 127736 0001–0004; H₂SO₄, FeCl₂, HCl, Javel/NaOCl, PAC 31% tested by TÜV Rheinland #248162921-01–05). Every shipment includes batch COA/MSDS.
See the FeCl₂ product page, FeCl₂ and ZDHC documentation for dyeing wastewater and the chemical catalogue for textile dyeing.
Frequently asked questions
Is ZDHC mandatory for dyeing mills in Vietnam?
Not under Vietnamese law. It is a commercial requirement set by brands through supplier programmes or contracts; national wastewater standards still apply in parallel.
What should I ask for when a supplier says “ZDHC MRSL v3.1 Level 1 conformant”?
Ask which document it is: ChemCheck/Level (verifiable on Gateway) or a laboratory test report. Also request the current SDS and batch COA, and match them to your CIL. If the brand requires a Level and the supplier holds only a test report, that is not enough.
Does Loc Thien FeCl₂ have a ZDHC Level?
Yes. Loc Thien’s FeCl₂ holds a Conformance Summary Report (CSR #248162921-02, dated 22 October 2024) achieving ZDHC MRSL Version 3.1 Conformance Level 1 alongside Analytical Test Report #248162921-02a (dated 23 October 2024, Smart testing 5 substance groups — PASS) issued by TÜV Rheinland Vietnam Co., Ltd.
Contact: send your request, get a quote within 15 minutes
Send your chemical list and the brand’s document requirements via the contact page to receive a quote within 15 minutes, with COA/MSDS guidance.
Hotline: 0979 891 929 · Email: [email protected]
References: ZDHC MRSL · ZDHC MRSL Conformance Guidance V2.1 · ZDHC Gateway – ChemCheck · Wastewater and Sludge Guidelines V2
LOC THIEN INVESTMENT DEVELOPMENT CO., LTD — Tax Code 0313650856 FeCl₂: ZDHC MRSL v3.1 test report · TUV Rheinland Vietnam #248162921-02a
Technical Support & B2B Procurement Hotline
Loc Thien Chemical specializes in direct manufacturing of FeCl₂ / FeCl₃ and direct industrial supply of basic chemicals (NaOH, HCl, H₂SO₄, PAC, NaOCl, H₂O₂, FeSO₄) with direct B2B pricing and dedicated 5–30-ton tanker delivery across Vietnam.
- Hotline / Zalo: +84 979 891 929
- Official Email: [email protected]
- Direct Manufacturer: Ferrous Chloride (FeCl₂ 30%) & Ferric Chloride (FeCl₃ 38–40%)
- Primary Supplier: NaOH 32%/45%/50%/99%, HCl 32%, H₂SO₄ 98%, PAC 30–31%, NaOCl 10–12%, H₂O₂ 35%/50%
- Compliance & Quality: FeCl₂ ZDHC MRSL v3.1 test report (Smart testing, 5 substance groups, TUV Rheinland Vietnam), ISO 9001:2015, Quatest 3, Full COA & GHS SDS
Complete Lookup Table: Loc Thien’s 9 Flagship Chemicals with Official ZDHC MRSL Version 3.1 Conformance Level 1 Documentation
To directly support Environmental Compliance (EHS / Sustainability), Chemical Management (CMS), and Procurement teams at textile dyeing, garment washing, printing, and footwear mills supplying Nike, Adidas, Zara (Inditex), Uniqlo (Fast Retailing), H&M, Puma, and Levi’s, below is the official portfolio of 9 basic chemicals and wastewater treatment coagulants from LOC THIEN INVESTMENT DEVELOPMENT CO., LTD (MST: 0313650856) verified to ZDHC MRSL Version 3.1 Conformance Level 1 by ZDHC-accepted independent testing bodies (TÜV SÜD and TÜV Rheinland):
| Documentation Group | No. | Chemical Product & Specification Link | Certifying / Testing Body | Certificate No. / CSR & Analytical Test Report No. | Primary Application in Textile Dyeing & ETP |
|---|---|---|---|---|---|
| Group I: Certificate Level 1 | 1 | Liquid Caustic Soda NaOH 32%–50% | TÜV SÜD Product Service GmbH / TÜV SÜD Vietnam | Cert No. ZDHC1 127736 0001 Rev. 00 · Report No. 2486017672-Q24VPS-CHM2869 | Cotton scouring, desizing, mercerizing & pH neutralization |
| Group I: Certificate Level 1 | 2 | Hydrogen Peroxide H₂O₂ 50% | TÜV SÜD Product Service GmbH / TÜV SÜD Vietnam | Cert No. ZDHC1 127736 0002 Rev. 00 · Report No. 2486017673-Q24VPS-CHM2869 | AOX-free oxidative bleaching & Fenton AOP oxidation |
| Group I: Certificate Level 1 | 3 | Anhydrous Sodium Sulphate Na₂SO₄ 99% | TÜV SÜD Product Service GmbH / TÜV SÜD Vietnam | Cert No. ZDHC1 127736 0003 Rev. 00 · Report No. 2438023996 | Neutral electrolyte exhaustion agent for reactive/direct dyeing |
| Group I: Certificate Level 1 | 4 | Soda Ash Light Na₂CO₃ 99.2% | TÜV SÜD Product Service GmbH / TÜV SÜD Vietnam | Cert No. ZDHC1 127736 0004 Rev. 00 · Report No. 2438023998 | Alkaline buffer (pH 10.5–11.2) for covalent reactive dye fixation |
| Group II: CSR & Test Report Level 1 | 5 | Sulfuric Acid H₂SO₄ 98% | TÜV Rheinland Vietnam Co., Ltd. | CSR & Report No. 248162921-01 (22/10/2024) | Alkaline dyeing effluent neutralization & Fenton pH conditioning (pH 3.0–3.5) |
| Group II: CSR & Test Report Level 1 | 6 | Ferrous Chloride Solution FeCl₂ 30% (Direct Manufacturer) | TÜV Rheinland Vietnam Co., Ltd. | CSR No. 248162921-02 · Test Report No. 248162921-02a (22–23/10/2024) | Primary decolorizing reducing agent (cleaving -N=N- Azo bonds) & Fenton Fe²⁺ catalyst |
| Group II: CSR & Test Report Level 1 | 7 | Hydrochloric Acid HCl 32% | TÜV Rheinland Vietnam Co., Ltd. | CSR & Report No. 248162921-03 (22/10/2024) | pH adjustment, ion-exchange resin regeneration & post-bleaching neutralization |
| Group II: CSR & Test Report Level 1 | 8 | Sodium Hypochlorite Javel NaOCl 10%–12% | TÜV Rheinland Vietnam Co., Ltd. | CSR & Report No. 248162921-04 (22/10/2024) | Machine stripping/cleaning, water disinfection & odor scrubbing |
| Group II: CSR & Test Report Level 1 | 9 | Poly Aluminium Chloride PAC 31% | TÜV Rheinland Vietnam Co., Ltd. | CSR & Report No. 248162921-05 (22/10/2024) | Primary coagulant for TSS, colloidal dye & COD removal in ETP |
Industrial Field Operation & Batch Quality Verification
1. Incoming Batch COA Verification & Regulatory Compliance (Law on Chemicals 69/2025/QH15)
When operating industrial water treatment, surface finishing, or textile dyeing lines in Vietnam, engineering teams must verify every chemical delivery against its batch-specific Certificate of Analysis (COA) and 16-section GHS Safety Data Sheet (SDS). Under the Vietnam Law on Chemicals No. 69/2025/QH15, Decrees 24/2026/ND-CP, 25/2026/ND-CP, and 26/2026/ND-CP, and QCVN 40:2025/BTNMT on industrial wastewater discharge:
- Specific Gravity & Assay Verification: Upon arrival of a 5–30-ton tanker or IBC tote shipment, plant QA technicians measure specific gravity at 20 °C using a calibrated hydrometer and cross-check active concentration against the batch COA issued by Loc Thien Chemical and verified via Quatest 3 (ISO/IEC 17025).
- Impurity & Heavy Metal Control: Trace heavy metals (Fe, Pb, As, Hg, Cd, Cr⁶⁺) and insoluble matter are strictly controlled to prevent catalyst poisoning in Fenton reactors, membrane fouling in RO/UF systems, or shade deviations in reactive textile dyeing.
- ZDHC MRSL v3.1 Level 1 Portfolio Boundary: For export-oriented textile and footwear FDI factories, Loc Thien Chemical maintains official ZDHC MRSL v3.1 Conformance Level 1 documentation for exactly 9 core products: four products certified by TUV SUD Product Service GmbH (
NaOH,H2O2,Na2SO4,Na2CO3) and five products verified via Conformance Summary Report (CSR) and Analytical Test Report by TUV Rheinland Vietnam (H2SO4,FeCl2,HCl,Javel/NaOCl,PAC 31%).
| Control Stage | Inspection Parameter | Test Method / Standard | Operational Target |
|---|---|---|---|
| Pre-Unloading Check | Seal integrity, UN/GHS hazard placards, batch COA & SDS | Visual & Document Audit | 100% match with delivery manifest |
| On-Site Sampling | Specific gravity (20 °C), visual clarity, pH / assay | ASTM / TCVN / Hydrometer | Within ±0.5% of COA specification |
| Dosing Skid Calibration | Metering pump stroke & frequency, back-pressure valve, ORP/pH probe | 2-Point Buffer Calibration | Dosing accuracy ±1.5%, stable effluent |
| Storage Safety Audit | HDPE/FRP tank vents, secondary containment dike (110% volume), eyewash | OSHA / Vietnam EHS | Zero vapor leak, immediate emergency readiness |
2. Dosing Optimization, Storage Materials & Preventive Maintenance
- Compatible Wetted Materials: Use cross-linked high-density polyethylene (XLPE / HDPE), polypropylene (PP-H), fiberglass-reinforced plastic (FRP with vinyl ester resin), or PTFE/PVDF-lined piping depending on corrosive and thermal conditions. Avoid unlined carbon steel or incompatible elastomers.
- Automated Dosing Control: Integrate diaphragm metering pumps with real-time pH, ORP (mV), turbidity, or conductivity sensors. Always perform a 5-beaker Jar Test whenever raw water COD, TSS, or alkalinity shifts by more than 15%.
- Secondary Containment & PPE: Storage tanks must sit inside an acid/alkali-resistant bund wall holding at least 110% of the largest tank volume. Operators handling unloading hoses must wear splash-proof chemical goggles, acid/alkali-resistant nitrile or neoprene gloves, face shields, and emergency respirators.
3. Multi-Role B2B Value Matrix (Procurement · QA/EHS Engineer · Plant Director)
- For Procurement Managers: Loc Thien Chemical is the direct manufacturer of FeCl2 30% solution and FeCl3 38–40% wastewater grade (3,000+ tons/month capacity), and a Tier-1 bulk commercial supplier of NaOH, HCl, H2SO4, PAC, NaOCl, H2O2, FeSO4, and Na2SiO3. Pricing is transparently structured around 5 technical cost drivers (active assay, packaging format, delivery distance from our 6 warehouses, order volume, and scheduled contract cadence) with a 15-minute technical quotation SLA.
- For Environmental & Process Engineers: Full technical support for Jar Test optimization, stoichiometry calculation, sludge minimization, and QCVN 40:2025/BTNMT compliance auditing.
- For FDI Plant Directors: Guaranteed supply continuity via 6 regional warehouses (Ba Ria - Vung Tau, Dong Nai, Binh Duong, Da Nang, Can Tho, Bac Ninh) and a dedicated 5–30-ton tanker fleet (4 hours in inner HCMC, 24–48 hours across Southern & Mekong Industrial Parks, 2–3 days in Northern & Central Vietnam).
4. Related Technical Resources & 15-Minute Quotation Gateway
- Explore our full industrial catalog: Industrial Chemical Catalog | Technical Knowledge Hub | Request a 15-Minute Technical Quote
- Legal Head Office: 452/6B Tinh Lo 10, Binh Tri Dong Ward, Binh Tan District, Ho Chi Minh City, Vietnam (Head Office only — all physical stock is dispatched from our 6 regional industrial park warehouses).
- 24/7 Technical Hotline: 0979 891 929 (Please contact hotline 0979 891 929 for detailed delivery procedures) | Official Email: [email protected]
Extended Engineering Calculation Example & Jar Test Protocol for Fashion Brand ZDHC Requirements for Dyeing Mills 2026
In a representative industrial wastewater treatment or surface treatment facility operating at a design flow of 1,200 m³/day (Technical Illustrative Example), process engineers evaluate dosing stoichiometry across three operating scenarios: baseline load, peak shift load (+25% COD/TSS), and seasonal rain dilution. Using calibrated 1,000 mL Jar Test beakers (rapid flash mixing at 180 rpm for 90 seconds, slow flocculation at 35 rpm for 15 minutes, and quiescent settling for 30 minutes), the plant establishes an optimal dosing curve that reduces chemical consumption by 12–18% while maintaining settled water turbidity below 3 NTU and effluent parameters well within QCVN 40:2025/BTNMT Column A. Every bulk shipment from Loc Thien Chemical includes batch-traceable COA analysis, GHS/SDS sheets, and on-site technical support across all 6 regional warehouses in Vietnam.
