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Table 5B External separation distances

Hazard Type 1 in an unmounded metal-built building, with a detonator annex attached – normal distances

Quantity of explosives (kg) Separation distance (m)
Footpath, lightly used road, waterway Minor road, railway line* Major road, place of public resort Buildings† Vulnerable building distance
0.1 – 10 10 16 31 48‡ 40
10 – 20 12 18 36 50‡ 42
20 – 30 13 19 38 52‡ 44
30 – 40 14 21 41 54‡ 46
40 – 50 14 22 43 56‡ 48
50 – 60 15 23 45 58‡ 48
60 – 70 16 24 47 60‡ 52
70 – 80 16 25 49 63‡ 57
80 – 90 17 26 51 70‡ 61
90 – 100 18 27 53 77‡ 66
100 – 150 21 32 63 110‡ 86
150 – 200 25 50 74 143‡ 104
200 – 300 31 47 94 209‡ 136
300 – 400 38 58 115 275‡ 165
400 – 450 42 63 125 308‡ 178
450 – 500 43 64 128 309‡ 191
500 – 600 45 68 135 311‡ 216
600 – 700 47 71 142 312‡ 238
700 – 800 49 74 148 314‡ 260
800 – 900 52 78 155 316‡ 280
900 – 1 000 54 81 162 318‡ 300
1 000 – 1 100 56 85 169 319‡ 319
1 100 – 1 200 58 88 175 321‡ 337
1 200 – 1 300 61 91 182 323‡ 354
1 300 – 1 400 63 95 189 325‡ 370
1 400 – 1 500 65 98 195 326‡ 386
1 500 – 1 600 67 101 202 328‡ 402
1 600 – 1 700 70 105 209 330‡ 416
1 700 – 1 800 72 108 215 332‡ 431
1 800 – 1 900 74 111 222 333‡ 444
1 900 – 2 000 77 115 229 335‡ 458
2 000 – 3 000 95 143 285 363‡ 570
3 000 – 4 000 109 164 328 370‡ 656
4 000 – 5 000 121 181 362 362 724
5 000 – 10 000 158 238 475 475 950
10 000 – 15 000 182 274 548 548 1 097
15 000 – 20 000 202 303 606 606 1 211
20 000 – 25 000 218 327 653 653 1 306
25 000 – 30 000 232 348 695 695 1 389

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.

Definition of terms

‘Footpath’ includes a bridleway or other thoroughfare which is not a road, but does not include a footpath used by no more than 20 persons every 24 hours.

‘Lightly used road’ means a road used by more than 500 vehicles every 24 hours.

‘Minor road’ means a road used by more than 500 vehicles every 24 hours, other than a major road.

‘Major road’ means a road used by more than 10 000 vehicles every 24 hours.

‘Waterway’ does not include a waterway navigated by no more than 20 persons every 24 hours.

* Use these distances also for any aerodrome, dock, pier, jetty, river wall, sea wall, reservoir.
† Use these distances for any dwelling, retail shop, government and public buildings, church, college, chapel, school, hospital, theatre, cinema or other building where the public are accustomed to assemble; motorway; caravan site for which planning permission for this use has been granted and on which is located an occupied caravan for a total period in excess of 28 days in any one calendar year; factory; building or works used for the storage in bulk of petroleum spirit, gas, or other inflammable substances; buildings or works used for the storage and manufacture of explosives or of articles which contain explosives.

‡ These distances may be reduced if certain criteria are met – see Table 5B1.

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Updated: 2011-10-21