The core cycle for the inspection of explosion-proof electrical equipment is once every three years, which is mainly based on the national standards AQ 3009-2007 and the GB/T 3836 series. The inspection must be conducted by institutions with professional qualifications.

I. Cycle for the Inspection of Explosion-Proof Electrical Equipment

1. Mandatory Inspection Requirements

Professional inspection cycle: No more than 3 years, as stipulated in Clause 5.2.4 of AQ 3009-2007.

Routine inspection: Conducted by the enterprise itself, with a cycle shorter than 3 years.

2. Special Circumstances

The inspection cycle shall be shortened in high-temperature or corrosive environments.

Re-inspection is required after equipment modification.

II. National Standards for the Inspection of Explosion-Proof Electrical Equipment

1. Core Standard System

AQ 3009-2007 Code of Safety for Electrical Explosion-Proof in Hazardous Areas

Specifies the inspection cycle, inspection items and filing requirements.

GB/T 3836 Series

GB 3836.1-2021: General Requirements for Equipment.

GB 3836.15-2024: Newly Added Code for the Design of Electrical Installations.

GB 50058-2014 Code for Design of Electrical Installations in Explosive Atmosphere Environments

2. Inspection Contents

Standardization of equipment selection and installation.

Line insulation and grounding status.

Integrity of explosion-proof structures (e.g., clearance of flameproof joint surfaces).