The Thai Industrial Standards Institute (TISI) has approved bringing crystalline silicon photovoltaic modules and a number of related PV products under mandatory industrial standard (TIS) control. The relevant ministerial regulations are expected to take effect in September 2026, after which PV products without TISI certification will no longer be lawfully imported, cleared or sold in Thailand.

TISI in brief

TISI is the Thai Industrial Standards Institute under the Ministry of Industry. It administers both voluntary and mandatory standards, each carrying a different mark. Many products — construction materials and electrical and electronic appliances among them — require mandatory certification; without a certificate the TISI mark cannot be applied and customs clearance is not possible.

Key policy: mandatory PV certification 2026–2027

Six categories of PV-related products will be subject to mandatory TISI certification: PV modules, PV DC circuit breakers, PV fuses, PV cables, PV lithium storage batteries and PV inverters. Each category corresponds to a separate Thai standard and requires a separate certificate. PV modules become mandatory in September–October 2026, with the supporting products following; the TIS 61215 standard is expected to become mandatory in 2027.

The certification process in full

(1) Eligibility

· The factory must hold an ISO 9001 certificate, and a local Thai importer must act as the applicant.

Two certification routes are available:

· Licence only — a factory inspection is carried out separately for each importer; or licence plus factory registration — once registered, additional customers do not require a repeat factory inspection, with surveillance every three years.

· Application documents: 13 categories of material, including factory qualifications, system documents, product information and importer information.

(2) Process

· Submit application → factory inspection and sampling → product testing → review and certification;

· PV modules may be exempted from testing in Thailand on the basis of an IEC test report issued within the previous three years by an ISO 17025 laboratory, but the factory inspection cannot be waived.

Surveillance after certification

Periodic surveillance

· Companies choosing the factory registration route undergo a factory system surveillance every three years;

· Surveillance takes the form of system audits and sampling and retesting in the market or at the factory.

Unannounced inspections

· TISI may inspect factories, import warehouses and offline retail outlets without prior notice, checking mark usage and product conformity;

· Violations lead to revocation of the certificate and prohibition of customs clearance.

Purpose of surveillance

· To ensure consistently stable production quality and prevent abuse of the TISI mark.

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