Explosivity of metallising dusts
To our knowledge (over 40 years of experience in the field of metallising companies), no explosion ever occurred in zinc and zinc-aluminium spraying booths.
The risk of explosion depends on the size of the metallising dust. Every coating operator must thus test the explosive character of the dust they produce.
For information, a few data:
- the values of the published general explosion parameters generally apply to relatively coarse powders;
- auto-ignition temperature in a layer: 540°C and in a cloud: 690°C;
- minimum auto-ignition energy (MIE): 640 to 960mJ;
- minimum explosion concentration: 460g/m3;
- maximum explosion pressure: 3.5 bars;
- Maximum pressure for pressure increase: 120 bars/s;
- flammability index: < 0.1. This 0.1 flammability index is considered to be low for such powders, but it strongly depends on the size of particles.
ISO 2063 Standard