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Table 3 External separation distances

Hazard Type 1 in a mounded brick-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 – 25 34 51 101 101 101
25 – 50 36 54 107 107 107
50 – 75 37 56 112 112 112
75 – 100 39 59 118 118 118
100 – 150 43 64 128 142‡ 128
150 – 200 46 69 139 156‡   139
200 – 300 54 81 161 180‡   161
300 – 400 54 92 183 163 183
400 – 450 64 97 193 193 193
450 – 500 68 102 204 204 204
500 – 600 68 102 204 204 216
600 – 700 68 102 204 231‡ 238
700 – 800 68 102 204 238‡   260
800 – 900 68 102 204 245‡   280
900 – 1 000 68 102 204 250‡   300
1 000 – 1 100 68 102 204 255‡   319
1 100 – 1 200 68 102 204 259‡   337
1 200 – 1 300 68 102 204 263‡   354
1 300 – 1 400 68 102 204 266‡   370
1 400 – 1 500 68 102 204 269‡   386
1 500 – 1 600 68 102 204 272‡   402
1 600 – 1 700 69 104 208 274‡   416
1 700 – 1 800 72 108 215 277‡   431
1 800 – 1 900 74 111 222 279‡   444
1 900 – 2 000 76 115 229 281‡   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 – 10 000 158 239 475 475 950
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 – 30 000 232 348 695 695 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 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