The table below gives you the formula for calculating external separation distances.
If you don't know which external separation distance table you should use, visit the page on separation distance tables.
| Type of explosive, store construction and density | Quantity of explosives (kg) | Formula for calculating separation distances (in metres) |
|---|---|---|
| Hazard Type 1 mounded brick store, reduced distance | 25 – 500 | R = 0.2167 * Q + 95.9167 |
| 500 – 1647 | R = 204 | |
| 1647 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 mounded brick store, normal distance | 100 – 300 | R = (73.84 * Q / (-3.364 + Q)) + (249.2 * Q / (413.1 + Q)) |
| 300 – 600 | As for reduced distance above | |
| 600 – 2000 | R = (73.84* Q / (-3.364 + Q)) + (249.2 * Q / (413.1 + Q)) | |
| 2000 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q ^ 2) ^ (1/6)) | |
| Hazard Type 1 unmounded brick store | 25 – 5600 | R = (93.75 * Q / (-3.492 + Q)) + (379.8 * Q / (273.8 + Q)) |
| 5600 – 19 603 | R = 0.010388771 * Q + 397.7274671 | |
| 19 603 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 mounded metal store, reduced distance | 75 – 243 | R = 0.114666667 * Q + 31.4 |
| 243 of more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 mounded metal store, normal distance | 75 – 300 | R = 0.138666667 * Q + 34.6 |
| 300 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 unmounded metal store, annex removed, reduced distance | 75 – 241 | R = 0.096 * Q + 35.8 |
| 241 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 unmounded metal store, annex removed, normal distance | 75 – 450 | R = 0.229333333 * Q + 31.8 |
| 450 – 2255 | R = 0.060848971 * Q + 107.6179629 | |
| 2255 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 unmounded metal store with annex, reduced distance | 75 – 450 | R = 0.205333333 * Q + 32.6 |
| 450 – 1917 | R = 0.067017231 * Q + 32.6 | |
| 1917 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 1 unmounded metal store with annex, normal distance | 75 – 450 | R = 0.661333333 * Q + 94.84224616 |
| 450 – 9922 | R = 0.017480771 * Q + 300.133653 | |
| 9922 or more | R = 22.4 * Q ^ (1/3) / ((1 + (3175 / Q) ^ 2) ^ (1/6)) | |
| Hazard Type 2 (every item of not more than 0.7 kg net mass per item) | - | R = 28.127 – 2.364 * LN (Q) + 1.577 * LN (Q) ^ 2 (minimum distance of 30 m) |
| Hazard Type 2 (some or all items of more than 0.7 kg net mass per item) | - | R = 167.648 + 70.345 * LN (Q) + 1.303 * LN (Q) ^ 2 (minimum distance of 30 m) |
| Hazard Type 3 | - | R = 6.4 * Q ^ (1/3) |
LN = natural log
R = distance in metres
Q = quantity (kg)
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