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Table 4 External separation distances

Hazard Type 1 in a mounded metal-built building – 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 7 11 21 23‡ 40
10 – 20 9 13 26 29‡ 42
20 – 30 10 15 30 33‡ 44
30 – 40 11 17 33 37‡ 46
40 – 50 12 18 35 40‡ 48
50 – 60 13 19 38 42‡ 48
60 – 70 13 20 40 44‡ 52
70 – 80 14 21 41 46‡ 57
80 – 90 14 21 42 47‡ 61
90 – 100 14 22 43 48‡ 66
100 – 150 16 32 49 55‡ 86
150 – 200 18 27 54 62‡ 104
200 – 300 23 34 68 76‡ 136
300 – 400 28 42 83 83 165
400 – 450 30 45 89 89 178
450 – 500 32 48 96 96 191
500 – 600 36 54 108 108 216
600 – 700 40 60 119 119 238
700 – 800 43 65 130 130 260
800 – 900 47 70 140 140 280
900 – 1 000 50 75 150 150 300
1 000 – 1 100 53 80 159 159 319
1 100 – 1 200 56 84 168 168 337
1 200 – 1 300 59 89 177 177 354
1 300 – 1 400 62 93 185 185 370
1 400 – 1 500 64 97 193 193 386
1 500 – 1 600 67 101 201 201 402
1 600 – 1 700 69 104 208 208 416
1 700 – 1 800 72 108 215 215 431
1 800 – 1 900 74 111 222 222 444
1 900 – 2 000 76 115 229 229 458
2 000 – 3 000 95 143 285 285 570
3 000 – 4 000 109 164 328 328 656
4 000 – 5 000 121 181 362 362 724
5 000 – 10 000 158 238 475 475 950
10 000 – 15 000 183 274 548 548 1 097
15 000 – 20 000 202 303 606 606 1 211
20 000 – 25 000 218 327 653 653 1 306
25 000 – 30 000 232 348 695 675 1 389

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 20 and fewer 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 3A.

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Updated: 2011-10-21