Study execution
How the study is executed
A structured, facilitated process — from scope definition through close-out — producing defensible, actionable outputs.
DHA Scoping & Process Inventory
Scope Dust Hazard Analysis per NFPA 660 (2024, superseding NFPA 652); compile combustible-dust inventory by location (mills, conveyors, dryers, dust collectors, silos); identify process-specific dust types, particle size distributions, and production rates; define DHA boundaries and applicable standards.
Combustibility / Explosibility Testing Programme
Design test programme covering Kst (ASTM E1226), Pmax, MIE (ASTM E2019), MIT (ASTM E1491 / E2154), MEC (ASTM E1515), LOC, and LIT; classify dust per St 0 / St 1 / St 2 / St 3 by Kst (0 / 0–200 / 200–300 / >300 bar·m/s); assess hybrid (gas + dust) atmosphere interactions — MIE depression and lowered MEC.
Ignition Source Inventory & Elimination
Identify and rank ignition sources per EN 1127-1 / IEC 80079-36 — hot surfaces, static electrostatic discharge, mechanical sparks, open flames, spontaneous combustion, electrical equipment, and lightning; specify ignition-source elimination controls per source type and dust St-class.
Explosion Protection Strategy Selection
Apply NFPA 660 / IEC 80079-37 protection hierarchy — prevention (inerting with N₂ / CO₂, LOC control, oxygen reduction), containment (pressure-shock-resistant design), mitigation (venting, suppression, isolation); specify combinations appropriate to vessel Kst class and process constraints.
Vent Sizing, Suppression & Isolation Design
Size explosion vents per NFPA 68 / EN 14491 (Kst-based, with K-factor and efficacy correction); design suppression systems per NFPA 69 (agent selection, nozzle coverage, system trigger delay); specify chemical / mechanical isolation valves to prevent flame and pressure propagation between vessels.
ATEX Zone Classification & Documentation Package
Produce ATEX Dust Zone 20 / 21 / 22 classification drawings per IEC 60079-10-2 for EU facilities; select equipment EPL Da / Db / Dc per zone; issue DHA finding register with risk ranking, vent sizing calculations, suppression/isolation specifications, ignition-source control schedule, housekeeping programme, and FM Global-aligned design dossier.
