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Table 5A1 External separation distances

Hazard Type 1 in an unmounded metal-built building, no 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 46 8 23
10 – 20 57 10 29
20 – 30 65 13 33
30 – 40 71 15 36
40 – 50 76 18 38
50 – 60 80 20 40
60 – 70 84 23 42
70 – 80 87 23 43
80 – 90 89 25 44
90 – 100 91 25 45
100 – 150 100 30 50
150 – 200 110 38 55
200 – 300 136 58 68
300 – 400 165 85 83
400 – 450 178 98 89
450 – 500 191 113 96
500 – 600 216 143 108
600 – 700 238 175 119
700 – 800 260 208 130
800 – 900 280 243 140
900 – 1 000 300 278 150
1 000 – 1 100 318 278 159
1 100 – 30 000 No reduced distances – use distances in column 5 of Table 5A regardless of density No reduced distances – use distances in column 5 of Table 5A regardless of density No reduced distances – use distances in column 5 of Table 5A 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 5A.

For certain quantities of explosives stored in buildings in low population density areas, the reduced separation distances in Table 5A1 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