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Table 5A External separation distances

Hazard Type 1 in an unmounded metal-built building, no 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 8 12 23 30‡ 40
10 – 20 10 15 29 35‡ 42
20 – 30 11 17 33 39‡ 44
30 – 40 12 18 36 42‡ 46
40 – 50 13 19 38 44‡ 48
50 – 60 13 20 40 46‡ 48
60 – 70 14 21 42 48‡ 52
70 – 80 14 22 43 50‡ 57
80 – 90 15 22 44 52‡ 61
90 – 100 15 23 45 55‡ 66
100 – 150 17 25 50 66‡ 86
150 – 200 18 28 55 78‡ 104
200 – 300 23 34 68 101‡ 136
300 – 400 28 42 83 124‡ 165
400 – 450 30 45 89 135‡ 178
450 – 500 32 48 96 138‡ 191
500 – 600 36 54 108 144‡ 216
600 – 700 40 60 119 150‡ 238
700 – 800 43 65 130 156‡ 260
800 – 900 47 70 140 162‡ 280
900 – 1 000 50 75 150 168‡ 300
1 000 – 1 100 53 80 159 168‡ 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 – 30 000 232 348 695 695 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 5A1.

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Updated: 2011-10-21