MSHA - Code of Federal Regulations - 30 CFR A57.6990A
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MSHA - Title 30 CFR
Appendix I to Subpart E--MSHA Tables of Distances


TABLE 1--SURFACE STORAGE OF EXPLOSIVE MATERIAL

 ----------------------+-----------------------------------------------------
  Quantity of explosive|          Minimum separation distances (feet)
    material (pounds)  |----------------------------|--------------------------
 ----------------------+ From mine buildings, dams |   Between magazines
                       |  and electric substations |------------|--------------
        Not over       |------------|----------------|           |
                       | Barricaded| Unbarricaded  | Barricaded| Unbarricaded
 ----------------------+-----------+---------------+-----------+-------------
                       |           |               |           |
            5          |     70    |      140      |     6     |      12
           10          |     90    |      180      |     8     |      16
           20          |    110    |      220      |    10     |      20
           30          |    125    |      250      |    11     |      22
           40          |    140    |      280      |    12     |      24
           50          |    150    |      300      |    14     |      28
           75          |    170    |      340      |    15     |      30
          100          |    190    |      380      |    16     |      32
          125          |    200    |      400      |    18     |      36
          150          |    215    |      430      |    19     |      38
          200          |    235    |      470      |    21     |      42
          250          |    255    |      510      |    23     |      46
          300          |    270    |      540      |    24     |      48
          400          |    295    |      590      |    27     |      54
          500          |    320    |      640      |    29     |      58
          600          |    340    |      680      |    31     |      62
          700          |    355    |      710      |    32     |      64
          800          |    375    |      750      |    33     |      66
          900          |    390    |      780      |    35     |      70
        1,000          |    400    |      800      |    36     |      72
        1,200          |    425    |      850      |    39     |      78
        1,400          |    450    |      900      |    41     |      82
        1,600          |    470    |      940      |    43     |      86
        1,800          |    490    |      980      |    44     |      88
        2,000          |    505    |    1,010      |    45     |      90
        2,500          |    545    |    1,090      |    49     |      98
        3,000          |    580    |    1,160      |    52     |     104
        4,000          |    635    |    1,270      |    58     |     116
        5,000          |    685    |    1,370      |    61     |     122
        6,000          |    730    |    1,460      |    65     |     130
        7,000          |    770    |    1,540      |    68     |     136
        8,000          |    800    |    1,600      |    72     |     144
        9,000          |    835    |    1,670      |    75     |     150
       10,000          |    865    |    1,730      |    78     |     156
       12,000          |    875    |    1,750      |    82     |     164
       14,000          |    885    |    1,770      |    87     |     174
       16,000          |    900    |    1,800      |    90     |     180
       18,000          |    940    |    1,880      |    94     |     188
       20,000          |    975    |    1,950      |    98     |     196
       25,000          |  1,055    |    2,000      |   105     |     210
       30,000          |  1,130    |    2,000      |   112     |     224
       35,000          |  1,205    |    2,000      |   119     |     238
       40,000          |  1,275    |    2,000      |   124     |     248
       45,000          |  1,340    |    2,000      |   129     |     258
       50,000          |  1,400    |    2,000      |   135     |     270
       55,000          |  1,460    |    2,000      |   140     |     280
       60,000          |  1,515    |    2,000      |   145     |     290
       65,000          |  1,565    |    2,000      |   150     |     300
       70,000          |  1,610    |    2,000      |   155     |     310
       75,000          |  1,655    |    2,000      |   160     |     320
       80,000          |  1,695    |    2,000      |   165     |     330
       85,000          |  1,730    |    2,000      |   170     |     340
       90,000          |  1,760    |    2,000      |   175     |     350
       95,000          |  1,790    |    2,000      |   180     |     360
      100,000          |  1,815    |    2,000      |   185     |     370
      110,000          |  1,835    |    2,000      |   195     |     390
      120,000          |  1,855    |    2,000      |   205     |     410
      130,000          |  1,875    |    2,000      |   215     |     430
      140,000          |  1,890    |    2,000      |   225     |     450
      150,000          |  1,900    |    2,000      |   235     |     470
      160,000          |  1,935    |    2,000      |   245     |     490
      170,000          |  1,965    |    2,000      |   255     |     510
      180,000          |  1,990    |    2,000      |   265     |     530
      190,000          |  2,010    |    2,010      |   275     |     550
      200,000          |  2,030    |    2,030      |   285     |     570
      210,000          |  2,055    |    2,055      |   295     |     590
      230,000          |  2,100    |    2,100      |   315     |     630
      250,000          |  2,155    |    2,155      |   335     |     670
      275,000          |  2,215    |    2,215      |   360     |     720
      300,000          |  2,275    |    2,275      |   385     |     770
 ----------------------+-----------+---------------+-----------+---------


For purposes of this table, "barricaded" means that the storage facility containing explosive material is screened effectively by a natural barricade or an artificial barricade consisting of a mound or revetted wall of earth with a minimum thickness of three feet.


TABLE 2--MSHA TABLE OF SEPARATION DISTANCES

         ------------+------------------------------+-------------
         Quantity of |  Storage facilities--minimum |
         ammonium    |   separation distances when  |   Minimum
         nitrate of  |   barricaded * (feet)        | thickness of
         blasting    |----------------|---------------|  artificial
         agents      |               |              | barricades**
         (pounds)    |   Ammonium    |   Blasting   |   (inches)
         ------------+   nitrate     |   agents     |
           Not over  |               |              |
         ------------+---------------+--------------+-------------
              100    |       3       |      11      |      12
              300    |       4       |      14      |      12
              600    |       5       |      18      |      12
            1,000    |       6       |      22      |      12
            1,600    |       7       |      25      |      12
            2,000    |       8       |      29      |      12
            3,000    |       9       |      32      |      15
            4,000    |      10       |      36      |      15
            6,000    |      11       |      40      |      15
            8,000    |      12       |      43      |      20
           10,000    |      13       |      47      |      20
           12,000    |      14       |      50      |      20
           16,000    |      15       |      54      |      25
           20,000    |      16       |      58      |      25
           25,000    |      18       |      65      |      25
           30,000    |      19       |      68      |      30
           35,000    |      20       |      72      |      30
           40,000    |      21       |      76      |      30
           45,000    |      22       |      79      |      35
           50,000    |      23       |      83      |      35
           55,000    |      24       |      86      |      35
           60,000    |      25       |      90      |      35
           70,000    |      26       |      94      |      40
           80,000    |      28       |     101      |      40
           90,000    |      30       |     108      |      40
          100,000    |      32       |     115      |      40
          120,000    |      34       |     122      |      50
          140,000    |      37       |     133      |      50
          160,000    |      40       |     144      |      50
          180,000    |      44       |     158      |      50
          200,000    |      48       |     173      |      50
          220,000    |      52       |     187      |      60
          250,000    |      56       |     202      |      60
          275,000    |      60       |     216      |      60
          300,000    |      64       |     230      |      60
        -------------+---------------+--------------+----------

* When the ammonium nitrate or blasting agents are not barricaded, the

distances shown in the table must be multiplied by six.
** For purposes of this table, "barricaded" means that the storage facility is screened effectually by a natural barricade or an artificial barricade consisting of amount of revetted wall or earth with the prescribed minimum thickness.

Note: At 56 FR 69596, December 30, 1993, appendix I to subpart E of part 57 is stayed until January 31, 1994.