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Table 5B1 External separation distances

Hazard Type 1 in an unmounded metal-built building, with a detonator annex attached – reduced distances for low-density dwelling

Quantity of explosives (kg) Reference zone radius (m) Maximum population count in reference zone Reduced distance to buildings (m) if maximum population count in reference zone not exceeded
0.1 – 10 62 13 31
10 – 20 71 15 36
20 – 30 77 18 38
30 – 40 82 20 41
40 – 50 86 23 43
50 – 60 90 25 45
60 – 70 94 28 47
70 – 80 98 33 49
80 – 90 102 35 51
90 – 100 106 40 53
100 – 150 127 50 63
150 – 200 147 68 74
200 – 300 188 110 94
300 – 400 229 163 115
400 – 450 250 193 125
450 – 500 257 203 128
500 – 600 270 225 135
600 – 700 283 248 142
700 – 800 297 273 148
800 – 900 310 298 155
900 – 1 000 324 323 162
1 000 – 1 100 337 350 169
1 100 – 1 200 350 380 175
1 200 – 1 300 364 408 182
1 300 – 1 400 377 440 189
1 400 – 1 500 391 470 195
1 500 – 1 600 404 505 202
1 600 – 1 700 417 538 209
1 700 – 1 800 431 573 215
1 800 – 1 900 444 610 222
1 900 – 2 000 458 648 229
2 000 – 3 000 570 1 003 285
3 000 – 4 000 656 1 328 328
4 000 – 30 000 No reduced distances – use distances in column 5 of Table 5B regardless of density No reduced distances – use distances in column 5 of Table 5B regardless of density No reduced distances – use distances in column 5 of Table 5B regardless of density

Column 1 gives two figures in each row for the quantity of explosives. For example, 25 – 50 kg means more than 25 kg and up to and including 50 kg.

There is no distance requirement for a quantity of explosives less than the minimum figure given in the table.

Where the quantity of explosives under consideration is greater than the maximum given in this table, the distance may be calculated using the appropriate formula .

Using reduced distances

The normal distances applying to buildings are in Table 5B.

For certain quantities of explosives stored in buildings in low population density areas, the reduced separation distances in Table 5B1 may be used if the applicant can confirm that the population count in the reference zone does not exceed the maximum.

If reduced distances are adopted, the applicant should continue to monitor population density to make sure that the reduced distances continue to apply.

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Updated: 2011-10-21