Shenzhen ZhongNuo Inspection Technology Co., Ltd. offers on-site explosion-proof electrical inspection, explosion-proof project acceptance services, and can provide explosion-proof rectification and construction services for non-compliant items.
Shenzhen Zhongnuo Testing Technology Co., Ltd. summarizes the experience from previous explosion-proof electrical inspections, common non-compliance items found during on-site explosion-proof electrical inspections:
Currently, China's hazardous chemical production enterprises are prone to frequent accidents, thus demanding a high priority on safety production inspections. We should gradually explore and clarify the safety performance of products and equipment involving personal safety, gradually forming a significant role in safety production inspections. Now, safety inspections can provide substantial technical support to hazardous chemical enterprises, particularly for electrical explosion-proof safety inspections, which should be widely promoted, continuously guiding and serving the enterprises in their safe production endeavors.
1. Design is not reasonable in hazardous areas
Many companies are constrained by their corporate history, and at the same time, the production materials of the enterprises are continuously changing, making the division of hazardous areas less orderly and appearing rather chaotic. The layout of equipment and facilities does not meet the explosion-proof requirements.
2. Understanding of explosion-proof knowledge is relatively weak
In many hazardous chemical enterprises, there is no distinction made between electrical explosion-proof safety inspections, fire protection electrical inspections, and building electrical inspections. In areas such as temporary power use, hot work operations, equipment replacement, and electrical management systems, there is a lack of standardized practices.
3. Improper installation of explosion-proof electrical equipment
Although many companies now have explosion-proof functions in electrical facilities, there are still many issues in installation, such as direct wiring connection of main lines, missing explosion-proof face screws, and using PVC pipes for wiring of incoming and outgoing pipelines. There are also problems with the installation of switches and sockets, terminal blocks, power and lighting distribution boxes, grounding systems, and the layout of electrical line systems, with many safety concerns.
4. Explosion-proof electrical wiring does not meet requirements.
In explosive environments, many companies currently do not place enough emphasis on explosion-proof electrical wiring, and they often fail to correctly understand the technical parameters of hazardous materials in dangerous areas, frequently resorting to haphazard wiring.
5. Non-standard grounding of explosion-proof electrical equipment
For explosion-proof electrical equipment grounding, the main types include internal neutral grounding, case protective grounding, and antistatic grounding. The grounding of unpowered metal cases is often inadequate, with frequent occurrences of grounding wires being connected to material pipelines.
6. There is a lack of overall planning for explosion-proof zones in the selection of power distribution rooms and control rooms.
Many distribution and control rooms are located within explosion-proof zones without proper measures in place.
7. Inadequate explosion-proof selection and requirements for explosion-proof electrical equipment
In electrical explosion-proof facilities, there is no distinction between environments with combustible dust and those with explosive gases; they are mixed and used together. In different hazardous areas, there are different electrical explosion-proof specifications, explosion-proof markings, and types, as well as varying levels and temperature classes. However, many companies mix and use explosion-proof electrical equipment without distinguishing these differences.

ZhongNuo Inspection offers explosion-proof site safety inspection services.
1. Explosion-proof safety inspections for electrical equipment in hazardous areas
2. Explosive Dust Explosion Proof Testing
3. On-site Assessment of Electrical Equipment in Dust Explosive Areas
4. Explosion-proof quality inspection and safety acceptance inspection for hazardous explosive site explosion-proof projects
5. Explosion-proof electrical and non-electrical equipment, as well as explosion-proof engineering consulting/renovation/construction/acceptance.
6. Various explosion-proof technology consulting services.

Application Agency for Explosion-Proof Electrical Construction Completion Inspection Report
It's widely known that after electrical work in explosive hazardous areas is completed, a third-party organization must conduct a post-completion inspection. Only upon passing the inspection can the facility be put into use. Additionally, beyond the company's regular checks, a facility with explosion-proof inspection qualifications must conduct periodic inspections every three years.
What are the main contents of the completion acceptance inspection we share here first?
Check if the explosion-proof electrical equipment has a label, Ex symbol, and clear identification of the type, class, and group of the explosion-proof equipment. Does the label indicate the explosion-proof certificate number issued by the inspection unit?
2. Verify that the type, classification, group, environmental conditions, and special markings of explosion-proof electrical equipment comply with regulations.
3. Inspect the shell of explosion-proof electrical equipment for cracks or damage; ensure the paint is intact, the junction box cover is securely fastened, and the fixing bolts and anti-loosening devices are in place.
4. Inspect oil-filled electrical equipment for oil leakage and seepage, ensuring the oil level meets specifications.
5. The ventilation and exhaust systems of explosion-proof electrical equipment with positive pressure should be unobstructed, connections should be properly made, and the installation locations of the inlet and outlet should meet the requirements.
6. Are the excess entry ports of explosion-proof electrical equipment properly sealed in accordance with regulations?
7. The installation of sealed or insulated devices in electrical circuits should comply with regulations.
8. The wiring engineering of intrinsic safety explosion-proof electrical equipment shall comply with the design requirements for the route and elevation of the lines; the lines should be marked with a sky blue sign.
9. The grounding or earthing of explosion-proof electrical equipment, as well as static electricity grounding, should meet the design requirements and be firm and reliable.
10. At the time of completion and acceptance, the relevant documents, materials, manufacturer's product user manuals, test records, qualification certificates, and installation drawings, along with other technical files, should be submitted.
11. At the time of inspection, the following measurement records should also be submitted:
Measurement records of single-side air gap for explosion-proof motor stator and rotor.
(2) Adjustment records for pressure-relief devices protecting explosion-proof electrical equipment against wind and air pressure, high-temperature records of the equipment's housing during trial operation, and test records of the grounding resistance for static electricity protection.
12. Explosion-proof electrical equipment operation records
The shell temperature of explosion-proof electrical equipment, including intrinsic safety and non-sparking types, should not exceed the specified limit.
(2) After the internal wiring in the junction box is securely fastened, the electrical clearances and creepage distances between the live parts and between the live parts and the metal housing shall comply with the specifications.
(3) The exhaust of explosion-proof electrical equipment with positive pressure should not emit sparks. When reducing wind pressure and air pressure, the low-pressure relay should operate reliably.
(4) The protective devices and interlock devices of explosion-proof electrical equipment should operate correctly and reliably.

How often should explosion-proof electrical equipment be inspected? How to obtain an explosion-proof electrical equipment inspection report?
Should explosion-proof electrical equipment in use be checked regularly? How often should a check report be issued? What standards explicitly stipulate this, and how are they defined, etc.? These are questions that many clients with explosive hazards in industries like chemicals, grain and oil, and gas stations are eager to know. ChinaNuotech will simply clarify these points for you.
Due to the industry's特殊性, facilities with explosive hazards must purchase and install equipment with official explosion-proof certification and ensure proper installation and maintenance. In addition, regular explosion-proof safety performance checks and routine inspections and maintenance of these electrical equipment must be conducted to confirm their continued explosion-proof capabilities. AQ3009-2007 "Electrical Explosion-Proof Safety Regulations for Hazardous Areas" also stipulates that periodic inspections should be carried out by safety production inspection and testing institutions with explosion-proof qualifications, with intervals generally not exceeding 3 years.
Zhenuo Inspection has provided on-site explosion-proof inspection and改造 services for various facilities such as gas stations, fuel depots, food factories, feed mills, and chemical plants, boasting a wealth of successful cases and industry experience.
If you happen to need to prepare a防爆电气检查报告 for such on-site requirements, feel free to message us for a detailed discussion.
On-Site Explosion-Proof Electrical Equipment Regular Inspection Consulting Service - Shenzhen Zhongnuo Inspection Technology Co., Ltd.