Factories / OEM

Getting GMP for your plant: from documents to inspection day

10 min read · Updated 9 Nov 2026

GMP certification steps in Thailand: two routes people call one

The GMP certification steps for a food plant in Thailand actually cover two routes that people tend to call one. The first is the premises audit against MOPH Notification No. 420 B.E. 2563 (2020), which produces an audit report used when applying for a food production licence. The second is a production system certificate from a certification body listed with the Thai FDA, which a plant shows to buyers and can use as evidence when renewing its licence.

Both routes use the same criteria: the annex to Notification No. 420 and the audit forms in the Thai FDA notification on auditing food premises. What differs is who audits, what document you receive and what you use it for. Most new plants go through the first route, then consider the second when customers ask to see a certificate.

This guide walks from preparing documents to audit day and what follows. It does not repeat the requirements clause by clause; those are in GMP 420 requirements and audit criteria. If you are new to the topic, start with what GMP is, and if you are wondering whether HACCP is also needed, read GMP vs HACCP.

Which food plants need GMP, and starting from your premises type

Clause 2 of Notification No. 420 requires every premises producing food for sale to follow good manufacturing practice, with some exceptions such as restaurants or places cooking food for immediate consumption, public street stalls, edible salt producers and fresh produce packing houses covered by their own notification. A restaurant that produces specifically controlled food, food with prescribed quality or standards, or food that must be labelled, using machinery of 5 horsepower or more or 7 or more workers, must still comply.

Factory or non-factory premises

The Thai FDA notification on applying for food production premises and the e-Submission manual divide premises into two types:

• Factory: machinery of 50 horsepower or more, or 50 or more workers. Apply on form Or.1 and receive a food production licence, Or.2.
• Non-factory: under 50 horsepower and under 50 workers. Apply on form Sor.Bor.1 and receive a premises number certificate, Sor.Bor.1/1.

Both types must meet GMP 420, and both Or.1 and Sor.Bor.1 applications must refer to a premises audit result.

Three specific requirement groups

On top of the five basic categories that apply everywhere, plants producing bottled drinking water, natural mineral water and ice, liquid pasteurised milk, or low-acid and acidified foods in hermetically sealed containers must meet specific requirements and appoint a trained production controller. The full licensing procedure is covered in the Thai food production licence.

Before you apply: a gap check against the audit forms

The most effective preparation step is to audit yourself with the same forms the inspectors use. The Thai FDA notification on auditing food premises under Notification No. 420 sets five forms:

• Tor.Sor.1: audit summary (the audit report)
• Tor.Sor.2: basic requirements, for every premises
• Tor.Sor.3: drinking water, natural mineral water or ice
• Tor.Sor.4: ready-to-drink liquid pasteurised milk
• Tor.Sor.5: low-acid and acidified foods in hermetically sealed containers

Score yourself the way inspectors do

Each basic requirement is scored good 2, fair 1, improve 0. Items that do not apply are removed from the maximum, and a percentage is calculated per category. To pass, every category must reach at least 60 percent and no major defect may be found. Specific requirements are pass or fail, and all must pass.

Close major defects first

The notification gives examples: no filling room or no control of post-process contamination; wrong food additive or wrong amount; water or ice below standard or without analysis at least once a year; no control of the microbial reduction step; no analysis of the finished product at least once a year; and, for dietary supplement plants, no production, distribution or recall records. A single item on this list means a fail even when category scores are high.

The output of this step should be a gap list showing which items need building work, which need equipment, which need written procedures and which need records to start, because each takes a different amount of preparation.

Records and documents that must exist before the audit

Inspectors look for evidence that the system works, not only at the condition of the building. The annex to Notification No. 420 requires a number of records and test results.

Records under the basic requirements

• Safety information for each raw material, and purchasing of qualified materials
• Records of weighing and mixing food additives
• Analysis of water and ice used as ingredients, by a government or accredited laboratory, at least once a year
• Records of the step that reduces or eliminates microorganisms
• Traceability information such as type, lot and source of raw materials, packaging and products
• Finished product analysis at least once a year
• Records of product types, production volume and sales, with a recall procedure, particularly for dietary supplements
• Handling of non-conforming product
• An internal quality audit at least once a year, with corrective actions
• Training evidence per position, chemical safety information and pest control measures

Records and reports must be kept for at least one year after the date shown on the label. Ministerial Regulation No. 1 (1979) also sets hygiene conditions, such as a medical check of workers at least once a year with the results kept on file.

Documents for the audit request

The citizen's manual on requesting a premises audit and the checklist for Or.1 or Sor.Bor.1 list documents such as a location map, site plan, scaled floor plans of every level, a machinery list with horsepower, the process and flow chart, water source, the formula in percent adding up to 100%, production volume, cleaning methods, waste disposal, number of workers and colour photos. Higher-risk foods, such as drinking water, pasteurised milk, foods in hermetically sealed containers and dietary supplements, need extra documents.

Applying for the premises audit through e-Submission

The premises audit route runs through the Thai FDA e-Submission system. The manual for applying for food production premises (revision 1) and the citizen's manual describe this sequence:

1. Create a verified identity with Open ID or the ThaID app.
2. Request system access. Premises in Bangkok apply at the Thai FDA one-stop service centre; other provinces at the Provincial Public Health Office, with company documents and the appointment of the operator.
3. Request the audit, attaching plans and the documents on the checklist, then book the audit.
4. Receive the audit at the actual premises.

Choosing the auditor: officials or a listed body

The manual says an Or.1 or Sor.Bor.1 application may refer to either a report from Thai FDA or provincial officials, or an audit result from an inspection body registered with the Thai FDA. In the second case, officials must first record the premises details, which will appear on the licence, so check the name and address carefully.

The 2018 MOPH notification on listing inspection and certification bodies requires inspection bodies to be accredited to ISO/IEC 17020 and certification bodies to ISO/IEC 17021-1. They must not provide food management system consulting, and must not send staff who advised a client to audit that client. Keep the consultant and the auditor separate from the start.

Food factory GMP audit day: what inspectors look at

On audit day the inspectors walk the site, talk to workers and ask for past records, following the five basic categories in the annex to Notification No. 420.

Category 1: location and building

Distance from contamination sources, no unused items around the building, suitable drainage, a building that is easy to clean and keeps out animals and insects, enough production space arranged in process order, a filling room or filling-zone controls against post-process contamination, and adequate ventilation and lighting.

Category 2: equipment and machines

Food-contact surfaces made of materials that do not contaminate, equipment installed where it can be cleaned, smooth work surfaces, effective cleaning, regular maintenance, and scales and measuring devices with a suitable range and accuracy.

Category 3: process control

Selection and storage of raw materials, packaging, mixing of additives, water and ice quality, control of the microbial reduction step, filling and sealing, labels, internal transport, traceability, finished products, records and internal audits. This is where inspectors ask for the most documents.

Category 4: sanitation

Clean water for general use, enough toilets and hand-wash basins separated from production, changing rooms and lockers, pest control, waste management, and chemicals with safety data stored apart from production.

Category 5: personal hygiene

Workers free of the listed diseases and wounds, proper hand washing, clean gloves, hair covers, aprons and shoes, no jewellery in production areas, training evidence, and rules for visitors.

If there is no production on audit day, the notification lets inspectors assess readiness and evidence, then follow up later. New plants should therefore have working procedures and record forms ready even before real production data exists.

After the audit: corrections, the report and the licence

At the end of the audit the inspectors summarise the result on Tor.Sor.1 and list the defects found. The plant corrects them and sends evidence as instructed; if it still does not pass, a follow-up audit may be needed. The citizen's manual says an application is treated as abandoned if the applicant does not act as required, so assign one person to track the defect list.

Using the report

• The Or.1 or Sor.Bor.1 checklist requires the audit report scope to cover the types of food applied for and the report to be within the validity the checklist sets.
• File Or.1 or Sor.Bor.1 referring to the report, entering storage premises, food types, processes, horsepower and number of workers, with signed PDF attachments.
• After the licence is issued, request access linked to the licence number before applying for food serial numbers.

The citizen's manual on premises audits also covers adding food types or processes and moving premises, which require another audit. Plan new lines to meet GMP from the design stage.

Thai GMP certificate from a certification body

When buyers ask for a GMP certificate, they usually mean a certificate the plant can hand to customers. The Thai FDA notification on issuing production system certificates under legal criteria (2021) sets the rules:

• Apply to a certification body listed with the Thai FDA for the relevant scope, with a copy of the Or.2 licence, or the Sor.Bor.1 application or Sor.Bor.1/1 certificate.
• The body audits against the criteria and carries out a surveillance audit once a year.
• The certificate is valid for three years from signature; if the total score across all categories is at least 85 percent it states Excellence Level.
• If a surveillance audit fails and is not corrected in time, the body must withdraw the certificate and inform the Thai FDA.
• The certification mark may appear only on the certificate, never on food labels.

Using it for licence renewal

The Thai FDA notification on evidence for renewing a food production licence instead of an audit accepts either a valid production system certificate whose scope covers the licensed food, or a passing audit result no more than one year old.

Other standards treated as equivalent

The Thai FDA list of example standards equivalent to the annex of Notification No. 420 includes Codex GHPs and HACCP, ISO 22000, FSSC 22000 and other private schemes. Plants holding these should compare the scope with their food types, but must still pass the audit route used for the licence.

Preparing to pass on the first round

Based on the criteria and forms above, plants that pass on the first round usually have all of this done before the audit date:

• A self-assessment on Tor.Sor.2 and any relevant specific form, scored as inspectors would.
• Every major defect closed first, then categories below 60 percent addressed.
• Latest-year analyses of water, ice and finished product from a government or accredited laboratory.
• Production, sales, traceability and recall records that can be produced immediately.
• At least one internal audit completed, with corrective actions recorded.
• The premises name, address and scope checked before filing, because they appear on the licence.
• Staff briefed to answer questions about hand washing, clothing and the steps they are responsible for.

For a gap review before the real audit, contact our team. If you want help building the system from the start, see factory setup and GMP services, or search the full notifications in our archive.

Sources

1. ประกาศกระทรวงสาธารณสุข (ฉบับที่ 420) พ.ศ. 2563 ออกตามความในพระราชบัญญัติอาหาร พ.ศ. 2522 เรื่อง วิธีการผลิต เครื่องมือเครื่องใช้ในการผลิต และการเก็บรักษาอาหาร · Open source · Search our archive
2. เรื่อง การตรวจประเมินสถานที่ผลิตอาหารตามประกาศกระทรวงสาธารณสุข (ฉบับที่ 420) พ.ศ. 2563 เรื่อง วิธีการผลิต เครื่องมือเครื่องใช้ในการผลิต และการเก็บรักษาอาหาร Re: Audit of food premises according to the · Open source · Search our archive
3. เรื่อง แนวทางการยื่นคำขออนุญาตสถานที่ผลิตอาหาร บังคับใช้ (In_force) 27/10/62 · Open source · Search our archive
4. คู่มือการยื่นคำขออนุญาตสถานที่ผลิตอาหาร · Open source · Search our archive
5. แบบตรวจสอบคำขอและบันทึกข้อบกพร่อง (checklist) กรณียื่นคำขอ อ.1 หรือ สบ.1 · Open source · Search our archive
6. 1.1 การขอตรวจประเมินสถานที่ (เป็นไปตามหลักเกณฑ์และเงื่อนไข) · Open source · Search our archive
7. ฉบับที่ 1 (พ.ศ. 2522) เรื่อง การขอรับใบอนุญาตตั้งโรงงานผลิตอาหารเพื่อจำหน่าย No. 1 B.E. 2522 (1979) Issued pursuant to the Food Act B.E 2522 (1979) · Open source · Search our archive
8. ฉบับที่ - เรื่อง กำหนดหลักเกณฑ์ วิธีการ และเงื่อนไข ในการได้มาซึ่งองค์กรผู้เชี่ยวชาญ หน่วยงานของรัฐ หรือองค์กรเอกชนทั้งในประเทศและต่างประเทศ เพื่อทำหน้าที่ในการตรวจสอบ หรือตรวจสถานประกอบการผลิตภัณฑ์อา · Open source · Search our archive
9. เรื่อง การออกหนังสือรับรองมาตรฐานระบบการผลิตตามหลักเกณฑ์ของกฎหมาย พ.ศ. 2564 Re: Issuance of a certificate of food production system standards according to the legal criteria B.E.2564 (2021). บังคับใช้ · Open source · Search our archive
10. เรื่อง กำหนดหลักฐานการขอต่ออายุใบอนุญาตผลิตอาหารแทนการตรวจประเมินว่าได้ปฏิบัติตามที่รัฐมนตรี ประกาศกำหนดวิธีการผลิต เครื่องมือเครื่องใช้ในการผลิต และการเก็บรักษาอาหาร ตามมาตรา 6 (7) บังคับใช้ (In_forc · Open source · Search our archive
11. ตัวอย่างมาตรฐานระบบการผลิตอาหารที่เทียบเท่าหรือไม่ต่ำกว่าบัญชีแนบท้าย ตามประกาศกระทรวงสาธารณสุข (ฉบับที่ 420) · Open source · Search our archive

This article is for general information. It is not a Thai FDA ruling or legal advice, and rules change — check the latest notification or ask an expert before filing or producing.

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