Electrical and MHE Issues MA11 Slide 1

Allocation of Electrical Categories MA11 Slide 2

Summary of Electrical Categories  Category A:Explosive gases present  Category B:Explosive Dust  Category C: Explosives, but no vapour/dust  Category D: Small quantities (except HD 1.1) MA11 Slide 3

Electrical Supply and Safety  External Power Supply: Depending on voltage: Public Traffic Route Distance, or Inhabited Building Distance  Internal (site) Power Supply: No overhead cables within 15m of buildings Use underground cables (but not under buildings) Surge protection devices Set distances for type of generating plant MA11 Slide 4

Electrostatic Precautions  Static electricity: Sources (and mitigation example): People (eg anti-static shoes and floor) Equipment (wheels made of antistatic material) Work benches (500mm from walls, and earthed) Racks (500mm from walls and ceiling, and earthed) Relative Humidity (RH) (Correct RH in room, conditioning of ammunition, sensors)  IATG 05:40 - extensive detail on this topic MA11 Slide 5

Lightening Protection  Low probability but severe consequence  Lightening Protection Systems (LPS) External – eg Faraday Cage Internal – eg Equipotential Bonding  Thunderstorm monitoring system  Evacuation Procedure MA11 Slide 6

Vehicles Permitted in Categorised Areas MA11 Slide 7

Vehicles Permitted to Enter a PES  Electrically operated vehicles  Diesel  Petrol engines  LPG, butane or propane powered vehicles MA11 Slide 8

‘Standard’ Vehicles in a PES  Permitted in a Category ‘C’ area, holding yard or marshalling yard if: Vehicle inspected to ensure no defects before entering the explosives area Area licensed for storage and handling only No ammunition processing in the area Stop engine before loading and restart after loading Loading/unloading by suitable MHE for the PES If vehicle emits sparks, stop engine, offload packages MA11 Slide 9

‘Standard’ Vehicles in an Explosives Area but not in a PES  Emergency vehicles permitted  Privately owned vehicles permitted if: Necessary to move staff around the site Privately owned vehicles have a fire extinguisher No increased fire risk from vehicle Written authority to use the vehicle Not allowed into PES  Contractors vehicles and MHE permitted: Meet IATG 05:50, or… use further control measures MA11 Slide 10

Management and Control of MHE  Serviceability  Maintenance and testing  Equipment breakdowns  Speed limits  Parked vehicles  Refuelling of MHE  Ventilation in buildings  Battery charging and maintenance MA11 Slide 11

Questions MA11 Slide 12