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Table 2 Internal separation distances

Inter-process building distances

Net explosive quantity (kg) Separation distance (m)
Hazard Type 1 Hazard Type 2 (<0.7 kg) Hazard Type 2 (>0.7 kg) Hazard Type 3 Hazard Type 4
50 18 15 32 12 11
100 22 15 32 15 11
200 27 22 61 18 11
300 30 24 69 21 11
400 33 25 75 23 11
500 36 27 79 25 11
1 000 56 31 92 32 12
2 000 85 36 105 40 19
3 000 106 40 112 46 23
4 000 122 42 117 50 24
5 000 134 44 121 54 25
10 000 176 50 133 68 27
15 000 204 54 140 78 27
20 000 225 57 144 86 27
25 000 243 60 148 93 27
30 000 258 62 151 98 27
40 000 275 66 156 110 27
50 000 295 68 159 120 27
60 000 315 70 162 130 27
80 000 345 74 166 140 27
100 000 375 76 170 150 27

The distances for quantities of explosives less than 50 kg should be taken to be the same as for 50 kg unless the explosives inspector advises otherwise.

Where the quantity of explosives under consideration lies between two quantities given in the table, interpolation may be used to determine the separation distance.

For quantities of explosives in excess of 100 000 kg, the explosives inspector will advise the distance required.

Separation distances for Hazard Type 1 and Hazard Type 2 are based on there being mounding or other equally effective measures to intercept low angle high-energy missiles arising from an explosion of Hazard Type 1 or 2 explosives.

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Updated: 2011-10-21