1 Scope
This national standard specified the requirements of explosion prevention and protection in area subject to dust explosion hazards.
This standard is applicable to the project design, manufacture management and imbursement & transportation of duct production.
This standard is not applicable to the mine, firecracker and explosive dust areas.
2 Normative Reference
The following normative documents contain provision which, through reference in this text, constitute provisions of this national standard. For dated reference, subsequent amendments to, or revisions of, any of these publications do not apply. But the parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For undated references, the latest edition of the normative document referred to applies.
GB/T 11651 Selection rules of articles for labor protection use
GB 12476.1 Electrical apparatus for use in the presence of combustible dust--Part 1-1: Electrical apparatus protected by enclosures and surface temperature limitation--Specification for apparatus
GB 15605 Guide for pressure venting of dust explosions
GB/T 17919 Directives for dust explosion protection for dust collectors in dust explosion hazardous area
GB/T 18154 Technical specification of automatic dust explosion suppression devices
GB 50057 Design code for protection of structures against lightning
GB 50058 Electrical installations design code for explosive atmospheres and fire hazard
GBJ 16 Code of Design on Building Fire Protection and Prevention
3 Terms and Definitions
The terms and definitions given below are applicable to this standard.
3.1 Combustible dust
The dust which may have fierce oxidizing reaction with gaseous oxidizer (mainly air).
3.2 Area subject to dust explosion hazards
The area where there may be combustible dust and gaseous oxidizer (mainly air).
3.3 Inerting
A kind of technology, by which adequate inert substance is filled into area subject to dust explosion hazards so that the dust mixture will loss explosivity.
3.4 Explosion suppression
A kind of explosion-control technology by which physicochemical action is applied to extinguish flame during explosion so that the unexploded dust will not join in explosion.
3.5 Explosion arrestment
A kind of explosion-control technology, by which it set up tools able to prevent flame and prevent or blanking wave in passage with combustible dust so as to block explosion within a certain scope.
3.6 Venting of dust explosion
A kind of explosion-control technology. When there is explosion inside with dust and mainly air, high-temperature pressurized combustion product and unburned substance are vented out to safe area through vulnerable part before the explosion pressure reaches the ultimate strength of enclosure so that the enclosure will not be damaged.
3.7 Subsequent explosion
A kind of continuous explosion caused by subsequent flame ignition after the settled dust is raised again by the shock wave of initial explosion to form dust cloud when the dust explosion occurs.
