How to evaluate the safety of explosion-proof workshops in chemical companies?

Evaluating the safety of explosion-proof workshop design in chemical companies requires a comprehensive consideration of four dimensions: building layout, explosion control, structural protection, and systematic safety management. The core indicators and verification methods are as follows:
? 1、 Assessment of Building Layout Safety
Hazard isolation
Explosion risk equipment is centrally arranged and isolated from non explosion proof areas using reinforced concrete blast walls of ≥ 200mm, with a safety distance of ≥ 50 meters (avoiding traffic arteries and critical facilities).
The explosion process is located on the top floor of a multi story factory building, and flammable equipment is placed against the exterior wall to facilitate explosion release.
Functional zoning
Divide hazardous areas according to the characteristics of explosive substances (such as Zone 0/1/2), and clarify the requirements for matching the protection level of electrical equipment (such as Ex d Ⅱ B T4).
? 2、 Verification of the effectiveness of explosion control
Design of pressure relief facilities
The ratio of pressure relief area to plant volume should be ≥ 0.03m ²/m ³ (national standard bottom line), with priority given to 0.05-0.10m ²/m ³.
Adopting lightweight pressure relief roof (self weight ≤ 60kg/m ²) or directional explosion relief wall, starting when overpressure is 0.02-0.05MPa, with fragment size ≤ 5cm.
Pressure relief direction and linkage
The release direction should be pre-set with a safe passage to avoid densely populated areas;
Linkage with explosion suppression system (such as chemical inhibitor spray response time<explosion pressure rise time).
?️ 3、 Structural protection capability testing
Anti explosion structure verification
The load-bearing frame is made of reinforced concrete, and the walls are filled with lightweight fire-resistant materials such as rock wool sandwich panels.
Regularly detect structural corrosion and deformation (such as using infrared thermal imaging to scan hot spot areas).
Compliance of equipment protection
Electrical equipment explosion-proof level matching area risk (such as IIC level covering IIB scenarios), grounding resistance<4 Ω;
Static cross connection of pipeline flange, limited liquid flow rate to prevent friction and electrification.
⚙️ 4、 Systematic security management review
Monitoring and early warning mechanism
Deploy combustible gas detectors in explosive hazardous areas, issue real-time alarms for concentration exceeding limits, and link with exhaust systems;
Electrostatic potential monitoring (threshold ≤ 3kV) and periodic testing of grounding resistance (≤ 1 Ω per month).
Operations and Emergency Management System
Develop equipment maintenance checklist (such as pressure vessel annual inspection, safety valve calibration);
Evacuation channel width ≥ 1.4 meters, equipped with gas masks and explosion-proof equipment, annual drills ≥ 8 hours;
The contingency plan includes graded response (local explosion/systematic explosion) and external rescue linkage.
Standardization of management processes
Establish a dust/gas risk classification and control ledger, and implement the "responsibilities, measures, funds, time limits, and contingency plans" for hidden danger rectification;
The operating procedures should indicate explosion risk points (such as static electricity accumulation) and corresponding prevention and control measures.