Shenzhen Zhongnuo Testing Technology Co., Ltd. is based in South China and offers consulting services in explosion-proof construction, safety inspections, renovations, project acceptance, and explosion-proof installations. We are well-versed in explosion-proof construction standards, boasting experienced construction teams with extensive practical experience. We have served major corporations such as China National Petroleum Corporation, LG, Hanlan Environment, BOE Technology Group, and Sinovac Biotech, receiving consistent praise and trust from our clients!
In recent years, with the continuous development of society and the increasing prominence of safety accidents, people's awareness of safe production has been rising, and the treatment of potential hazards in hazardous environments is urgent.
In numerous industrial sectors in our country, such as oil, chemicals, ports, coal, and others, leaks or spills of various flammable and explosive gases, liquids, dusts, and fibers may occur during production, processing, transportation, and storage. When these substances mix with air, they can form explosive mixtures. Once the concentration of the mixture reaches the explosive range, a spark can trigger explosions and severe fires, even leading to catastrophic chain reactions. Therefore, equipment used in such hazardous environments must be certified and equipped with explosion-proof features. The use of all explosion-proof environment equipment requires installation and debugging by experienced engineering companies in strict accordance with explosion-proof construction specifications and acceptance standards before being put into actual production use. This ensures the maximum safety requirements for all stages of the production process.

Based on the basic requirements of GB 15577 "Safety Code for Dust Explosion Prevention," in the construction and renovation for explosion-proof in dusty explosive areas, the following five main explosion-proof measures can be adopted (shared by Shenzhen ZhongNuo Testing Technology Co., Ltd.).
Anti-knock
1. Definition: An explosion suppression technology that allows the containment to withstand the pressure of a large-scale explosion when combustible dust and gaseous oxidizers or air are present within, preventing the containment from being destroyed.
2. Objective: By enhancing container wall thickness and improving material, external damage is minimized even in the event of a dust explosion.
3. Basic Requirements:
When handling powdered materials that could cause an explosion, if there is no explosion suppression device and no pressure relief measures, all process equipment should be designed to be explosion-proof and capable of withstanding the overpressure generated by an internal explosion without rupture.
(2) The connection parts between various process equipment (such as pipes, flanges, etc.) should have the same strength as the equipment itself. For connections between high-strength and low-strength equipment, explosion-proof devices should be installed.
(3) Equipment for explosion-proof pressure and explosion-proof pressure impact should comply with the requirements of GB/T 24626.
Explosion Relief
1. Definition: A suppression technology that, during an explosion within an enclosed package, releases the high-temperature, high-pressure combustion products and unburned materials through pre-set weak points on the package before the explosion pressure reaches the package's limiting strength, thus preventing the package from being destroyed.
2. Purpose: To reduce explosion losses by installing explosion relief devices.
3. Methods: Two types of venting methods are available – with flame venting and without flame venting.
4. Basic Requirements:
(1) If the strength of the process equipment is insufficient to withstand the overpressure generated by internal dust explosion under actual operating conditions, a venting port should be installed. The venting port should face a safe direction, and its size should comply with the requirements of GB/T 15605.
(2) Indoor dust explosion hazard process equipment should be vented to a safe outdoor direction through pressure relief ducts. The pressure relief ducts should be as short and straight as possible, with a cross-sectional area not less than that of the relief opening, and their strength should not be less than the strength of the protected equipment container.
(3) Equipment within the room that cannot vent explosive gases outdoors through a pressure relief conduit should be fitted with flameless venting caps.
(4) Process equipment with inline pipelines should be designed to withstand at least 0.1 MPa of internal overpressure.
Three: Explosion Suppression
1. Definition: In the initial stage of an explosion, extinguishing the flame and suppressing (preventing) the development of dust explosion through physical and chemical action.
2. Purpose: To pre-detect fire suppression and explosion inhibition through the installation of explosion suppression devices.
3. Basic Requirements:
Process equipment with a risk of dust explosion should be protected with explosion suppression devices.
(2) If a monitoring-type explosion suppression device is used, it should comply with the requirements of GB/T 18154.
(3) Explosion suppression system design and application should comply with the requirements of GB/T 25445.
Four, Explosion-proof
1. Definition: Technology that prevents the spread of an explosion through physical and chemical actions after the explosion occurs.
2. Purpose: To prevent the spread of flame through pipes or other conduits
3. Basic Requirements:
(3) Equipment and facilities with a dust explosion hazard that are interconnected through pipelines should ideally be equipped with explosion-proof devices on the pipelines.
(2) Equipment and facilities with a dust explosion hazard that are interconnected by pipelines should be equipped with explosion-proof devices on the pipelines. The shutdown direction should align with the direction of the explosion's propagation.
Five: Inertization
For processes such as crushing, grinding, drying of powders, and pneumatic conveying through pipelines in sealed containers, inert gases such as nitrogen, carbon dioxide, halogenated hydrocarbons, argon, helium, and steam, as well as inert dusts like fire extinguishing powder, chemical dry powder, and mineral rock powder are introduced. This is to dilute combustible components and reduce the oxygen content in the environment.

Standard for Explosion-proof Construction Acceptance - Shenzhen Zhongnuo Testing Technology Co., Ltd.
G50058 "Design Specification for Electrical Installations in Explosive Hazardous Environments"
GBJ54-83 "Code for Design of Low-Voltage Distribution Systems and Lines"
G50016 Building Design Fire Protection Code
AQ3009 Electrical Explosion-Proof Safety Code for Hazardous Areas
GB/T 3836.1 "Explosive Atmospheres – Part 1: Equipment – General Requirements"
GB/T3836.15 "Design, Selection, and Installation of Electrical Equipment for Explosive Environments"
GB50257 "Code for Construction and Acceptance of Electrical Installations in Explosive and Fire Hazardous Environments"
14J938 "Explosion-Proof and Explosion Relief Windows, Doors, Roof, and Wall Building Structures"

General Requirements for Explosion-Proof Workshop Design (Shared by Shenzhen ZhongNuo Inspection & Testing Technology Co., Ltd.)
4.1 Floor, Interior Wall
Areas producing flammable gases heavier than air or vapors of flammable and combustible liquids, as well as Class B production workshops with dust and fiber explosion hazards, should use non-sparking floors. To prevent sparks, the floors can be made of rubber, plastic, rubber mixed with graphite, or asphalt concrete.
Wall surfaces in workshops where combustible dust may settle should be plastered or painted to create an easily cleanable (washable) interior surface.
4.2 Office, Break Room
For personnel safety, do not establish offices or restrooms in Class A or B production buildings with explosion hazards. If necessary, such rooms can be located outside the workshop, separated from the workshop by non-combustible walls with fire resistance not less than 3.5 hours.
4.3 Electrical Equipment
Electrical equipment in explosion-proof workshops should be selected and installed based on different circumstances, opting for explosion-proof types such as explosion-proof switches, motors, and lighting fixtures, and strictly avoiding non-explosion-proof models.
4.4 Lightning Protection Facilities
In facilities and workshops prone to explosion, in addition to installing lightning protection devices on the building itself, it is required to set up grounded lightning rods around the building according to specifications. This ensures the building is within the protected range of the entire lightning protection system, preventing accidents caused by lightning strikes.
Explosion-proof electrical modifications and on-site explosion-proof construction consulting services for hazardous areas — Shenzhen ZhongNuo Testing Technology Co., Ltd.