(a) The threshold quantities set out below relate to each installation or group of installations belonging to the same occupier where the distance between installation is not sufficient to avoid, in foreseeable circumstances, any aggravation of major accident hazards. These threshold quantities apply in any case to each group of installations belonging to the same occupier where the distance between the installations is less than 500 metres.
(b) For the purpose of determining the threshold quantity of hazardous chemical at an isolated storage, account shall also be taken of any hazardous chemical which is:-
(i) in that part of any pipeline under the control of the occupier having control of the site wh.ch is within 500 metres of that site and connected to it;
(ii) at any other site under the control of the same occupier any part of the boundary of which is within 500 metres of the said site; and
(iii) in any vehicle, vessel, aircraft or hovercraft, under the control of the same occupier which is used for storage purpose either at the site or within 500 metres of it;
but no account shall be taken of any hazardous chemical which is in a vehicle, vessel, aircraft or a hovercraft used for transporting it.
Sl. No. |
Chemicals |
Threshold Quantities (tonnes) |
|
For application of Rules 4, 5 and 7-9 |
For application of Rules 10 to 15 |
||
1 |
2 |
3 |
4 |
1 |
Acrylonitrile |
350 |
5,000 |
2 |
Ammonia |
60 |
600 |
3 |
Ammonium nitrate (a) |
350 |
2,500 |
4 |
Ammonium nitrate fertilizers (b) |
1,250 |
10,000 |
5 |
Chlorine |
10 |
25 |
6 |
Flammable gases as defined in Schedule 1, paragraph (b) (i) |
50 |
300 |
7 |
Highly flammable liquids as defined in Schedule 1, paragraph (b) (ii) |
10,000 |
100,000 |
8 |
Liquid oxygen |
200 |
2,000 |
9 |
Sodium chlorate |
25 |
250 |
10 |
Sulphur dioxide |
20 |
500 |
11 |
Sulphur trioxide |
15 |
100 |
(a) This applies to ammonium nitrate and mixtures of ammonium nitrates where the nitrogen content derived from the ammonium nitrate is grater than 28 per cent by weight and to aqueous solutions of ammonium nitrate where the concentration of ammonium nitrate is greater then 90 per cent by weight
(b) This applies to straight ammonium nitrate fertilizers and to compound fertilizers where the nitrogen content derived from the ammonium nitrate is greater than 28 per cent by weight (a compound-fertilizer contains ammonium nitrate together with phosphate and/or potash).