Subchapter 7. General Industry Safety Orders
Group 18. Explosives and Pyrotechnics
Article 114. Storage of Explosives

§5252. Quantity and Distances Table for the Storage of Explosives.

(a) The quantity of explosive materials that may be kept or stored in any magazine shall conform to Table EX-1, Table of Distances, which sets forth the minimum distance that a magazine may be located from the nearest inhabited building or other magazine.

(b) The quantity and distance table is not applicable to any magazine if the nearest inhabited building is effectually screened from the magazine by a natural barrier, which:

(1) Is 40 feet or more in height at any point, above a straight line drawn from the top of any sidewall of the magazine to any part of the inhabited building; and

(2) Has a natural thickness of not less than 200 feet at the point where it is intersected by the straight line.

(c) All types of blasting caps in strength through No. 8 shall be rated at 1 1/2 pounds of explosives per 1,000 caps. For strengths higher than No. 8 cap, consult the manufacturer.

(d) For quantity and distance purposes detonating cord up to 60 grains per foot shall be calculated as equivalent to 9 pounds of high explosives per 1,000 feet. Heavier detonating cord shall be rated proportion- ately.

(e) When two or more storage magazines are located on the same property, each magazine must comply with the minimum distances specified from inhabited buildings, railways, and highways; and, in addition, they shall be separated from each other by not less than the distances shown for “Separation of Magazines,” except that the quantity of explosive materials contained in cap magazines shall govern in regard to the spacing of said cap magazines from magazines containing other explosive materials. If any two or more magazines are separated from each other by less than the specified “Separation of Magazines” distances, then such two or more magazines, as a group, must be considered as one magazine, and the total quantity of explosive materials stored in such group must be treated as if stored in a single magazine located on the side of any magazine of the group, and must comply with the minimum of distances specified from other magazines and inhabited buildings.

TABLE EX-1-AMERICAN TABLE OF DISTANCES FOR STORAGE OF EXPLOSIVES
As revised and approved by the Institute of Makers of
Explosives, November 5, 1971

QUANTITY OF EXPLOSIVES		Inhabited Buildings		Public Highways Class A to D		Passenger Railways- Public Highways with Traffic Volume of more than 3000 Vehiles/Day		Separations of Magazines
Pounds Over	Pounds Not Over	Barricaded	Unbarricared	Barricaded	Unbarricared	Barricaded	Unbarricared	Barricaded	Unbarricared
2 5 10 20 30	5 10 20 30 40	70 90 110 125 140	140 180 220 250 280	30 35 45 50 55	60 70 90 100 110	51 64 81 93 103	102 128 162 186 206	6 8 10 11 12	12 16 20 22 24
40 50 75 100 125	50 75 100 125 150	150 170 190 200 215	300 340 380 400 430	60 70 75 80 85	120 140 150 160 170	110 127 139 150 159	220 254 278 300 318	14 15 16 18 19	28 20 32 36 38
150 200 250 300 400	200 250 300 400 500	235 255 270 295 320	470 510 540 590 640	95 105 110 120 130	190 210 230 240 260	175 189 201 221 238	350 378 402 442 476	21 232 24 27 29	42 45 48 54 58
500 600 700 800 900	600 400 800 900 1000	340 355 375 390 400	680 710 730 780 800	135 145 150 155 160	270 290 300 310 320	253 266 278 289 300	506 532 556 578 600	31 32 33 35 36	62 64 66 70 72
100 1200 1400 1600 1800	1200 1400 1600 1800 2000	425 450 470 490 505	850 900 940 980 1010	165 170 175 180 85	330 340 350 360 370	318 336 351 366 378	636 672 702 732 756	39 41 43 44 45	78 82 86 88 90
2000 2500 3000 4000 5000	2500 3000 4000 5000 6000	545 580 638 685 730	1090 1160 1270 1370 1480	190 195 210 225 235	380 390 420 450 470	408 432 474 513 546	816 864 948 1025 1092	19 52 58 61 65	98 104 116 122 130
6000 7000 8000 9000 10000	7000 8000 9000 10000 12000	770 800 835 865 875	1540 1600 1670 1730 1750	245 250 255 260 270	490 500 510 530 540	573 600 624 645 687	1145 1200 1248 1290 1374	68 72 75 78 82	136 144 150 156 164
12000 14000 16000 18000 20000	14000 16000 18000 20000 25000	885 900 940 975 1055	1770 1800 1880 1950 2000	275 280 285 290 315	550 560 570 580 630	723 756 786 813 876	1445 1512 1572 1625 1752	87 90 94 98 105	174 180 186 196 210
25000 30000 35000 40000 45000	30000 35000 40000 45000 50000	1130 1205 1275 1340 1400	2000 2000 2000 2000 2000	340 360 380 400 420	680 720 760 800 840	933 981 1025 1058 1104	1886 1982 2000 2000 2000	112 119 124 129 135	224 238 248 258 270
50000 55000 60000 65000 70000	55000 60000 65000 70000 75000	1460 1515 1565 1610 1655	2000 2000 2000 2000 2000	440 455 470 485 500	880 910 940 970 1000	1140 1173 1206 1236 1263	2000 2000 2000 2000 2000	140 145 150 155 160	280 290 300 310 320
75000 80000 85000 90000 95000	80000 85000 90000 95000 100000	1695 1730 1760 1790 1815	2000 2000 2000 2000 2000	510 520 530 540 545	1020 1040 1060 1080 1090	1293 1317 1344 1368 1392	2000 2000 2000 2000 2000	165 170 175 180 185	330 340 350 360 370
100000 110000 120000 130000 140000	110000 120000 130000 140000 150000	1835 1855 1875 1890 1900	2000 2000 2000 2000 2000	550 555 560 565 570	1100 1110 1120 1130 1140	1437 1479 1521 1557 1593	2000 2000 2000 2000 2000	195 205 215 225 235	390 410 430 450 470
150000 160000 170000 180000 190000	160000 170000 180000 190000 200000	1935 1965 1990 2010 2030	2000 2000 2000 2010 2030	580 590 600 605 610	1160 1180 1200 1210 1220	1629 1662 1695 1725 1755	2000 2000 2000 2000 2000	245 255 265 275 285	490 510 530 550 570
200000 210000 230000 250000 275000	210000 230000 250000 275000 300000	2055 2100 2155 2215 2275	2055 2100 2155 2215 2275	620 635 650 670 690	1240 1270 1300 1340 1380	1782 1836 1890 1950 2000	2000 2000 2000 2000 2000	295 315 335 360 385	590 630 670 720 770

NOTES:

(1) Separation distances to prevent explosion of ammonium nitrate and ammonium nitrate-based blasting agents by propagation from nearby stores of high explosives or blasting agents referred to in the Table as the “donor”. Ammonium nitrate, by itself, is not considered to be a donor when applying this Table. Ammonium nitrate, ammonium nitrate-fuel oil or combinations thereof are acceptors. If stores of ammonium nitrate are located within the sympathetic detonation distances of explosives or blasting agents, one-half the mass of the ammonium nitrate should be included in the mass of the donor.

(2) The distances in the Table apply to ammonium nitrate that passes the insensitivity test prescribed in the definition of ammonium nitrate fertilizer promulgated by The Fertilizer Institute, and ammonium nitrate failing to pass said test shall be stored at separation distances determined by competent persons.

TABLE EX-3

Types of Storage Facilities

View Graphic

*As a result of tests with electric blasting caps, it has been determined that these blasting caps are not subject to sympathetic detonation. Therefore, a Type 4 storage facility meets the necessary requirements for storage of blasting caps that do not mass detonate.

NOTE

Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code; and Section 12006, Health and Safety Code.

HISTORY

1. Repealer and new section filed 10-17-75; effective thirtieth day thereafter (Register 75, No. 42).

2. Amendments filed 7-16-76; effective thirtieth day thereafter (Register 76, No. 29).

3. Amendment filed 9-18-80; effective thirtieth day thereafter (Register 80, No. 38).

4. Amendment of section heading, section and Note, including transfer of section 1938, App B, Plate B-14, table 1 to replace former Table EX-1; transfer of section 5253 Table EX-2 to new section 5252 Table EX-2; and transfer of section 1938, App B, Plate B-14a to new Table EX-3, filed 7-11-2003; operative 8-10-2003 (Register 2003, No. 28).

Go Back to Article 114 Table of Contents