[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §§1—4, 1-28-2004; Ord. No. 12-030 §1, 4-11-2012]
A. All
blasting operations within the County shall be conducted in strict
accordance with the following rules and regulations and it shall be
unlawful for any person to fail to observe and follow said rules and
regulations when blasting. In the event there is a violation of said
rules and regulations, the Director shall have the power and it shall
be his duty to revoke the blasting permit issued in connection with
the operation, revoke the license of the blaster in charge, all in
accordance with the terms of this Chapter, and in addition, the violator
or violators may be punished as otherwise provided by this Chapter
for violations thereof.
1. Blasting operations shall be carried on with the smallest possible
number of persons present.
2. Before firing any blast, all means of access to the danger zone (the
extent of which shall be determined by the blaster, but in no case
to be closer to the explosion than the blaster), shall be effectively
guarded to exclude all unauthorized personnel. When practical, the
blaster shall then sound a warning of sufficient intensity and duration
to be distinctly audible to all persons within the danger zone and
all such persons shall retire beyond the danger zone. The danger zone
shall then be examined by the blaster to make certain that all persons
have retired therefrom to a place of safety. No blast shall be fired
while any person is in the danger zone.
3. When the point of explosion is within three hundred (300) feet of
a roadway, the blaster shall, just prior to the blast, designate a
sufficient number of employees of the operator, each carrying a red
warning flag, to stop all vehicular and pedestrian traffic on each
possible route of travel within three hundred fifty (350) feet of
the point of explosion until the blast has been fired.
4. No person shall return to the danger zone until permitted to do so
by the blaster as announced by audible or visual signal.
5. Immediately following the blast the area shall be examined by the
blaster for evidence of misfired charges.
6. All misfires shall be reported at once to the superintendent or manager
who shall then determine the safe and proper method of disposal. The
unexploded charge shall be detonated if such can be accomplished without
risk of injury to personnel or damage to property.
7. When electric blasting caps are transported in a motor vehicle, equipped
with a radio transmitter, they shall either be in their original package
or stored in a closed metal box that is lined with a cushioning material
such as wood or sponge rubber. When the electric caps are being placed
into or removed from the box, the transmitter shall not be used.
8. Unless otherwise expressly authorized in writing by the Director,
all blasting operations shall be conducted at no less distance from
any fixed or mobile radio transmitter than indicated in the following
table:
|
Transmitter Power Output in Watts
|
Minimum Distance From Blasting Operations Using Electric
Blasting Caps, in Feet
|
---|
|
5—25
|
100
|
|
25—50
|
150
|
|
50—100
|
220
|
|
100—250
|
350
|
|
250—500
|
450
|
|
500—1,000
|
650
|
|
1,000—2,500
|
1,000
|
|
2,500—5,000
|
1,500
|
|
5,000—10,000
|
2,200
|
|
10,000—25,000
|
3,500
|
|
25,000—50,000
|
5,000
|
|
50,000—100,000
|
7,000
|
|
When it can be demonstrated by means of approved tests that
electric blasting may be carried out at lesser distances from the
transmitter than required by the table shown, the Director may allow
a variation from the requirements of said table.
|
|
When blasting operations are located near highways or other
public ways, signs shall be erected at least five hundred (500) feet
from the blast areas reading: "BLAST AREA - SHUT OFF ALL TWO-WAY RADIOS".
The letters of these signs shall be not less than four (4) inches
in height on a contrasting background.
|
9. Under no circumstances shall the amount of explosives taken within
three hundred (300) feet of a potential point of explosion exceed
the amount estimated by the blaster as necessary for the blast. Such
explosives shall be stacked in piles at least twenty-five (25) feet
from the nearest holes being loaded and at such distances apart and
that any premature explosion will not be likely to propagate from
one (1) pile to another.
10. The explosives containers, if any, shall be opened at the pile and
carried up to the hole, one (1) case or unit at a time for immediate
loading or placed at a loading station not less than six (6) feet
from the hole except that not more than one hundred (100) pounds of
explosives shall be allowed at the loading station at any one time.
All empty explosives containers (boxes, bags, crates, etc.) shall
be properly disposed of, daily, in a safe manner.
11. Explosives shall be distributed in such a manner that the distances
from storage piles to the allowable maximum quantity of one hundred
(100) pounds of explosives at the loading station or between such
one hundred (100) pound loading station piles shall not be less than
the quantities shown in the following quantity-distance table:
|
Pounds of Explosives
|
Distance Between Piles of Explosives in Feet
|
---|
|
up to 50
|
21
|
|
100
|
25
|
|
200
|
32
|
|
300
|
37
|
|
400
|
41
|
|
500
|
44
|
|
750
|
50
|
|
1,000
|
55
|
|
1,500
|
64
|
|
2,000
|
70
|
|
2,500
|
75
|
|
5,000
|
96
|
|
10,000
|
123
|
12. Excessively large amounts of explosives shall not be delivered to
the loading area at one (1) time. If deliveries of explosives are
made by truck, the quantity permitted at or near the loading operations
shall be limited to one (1) truck load. Other trucks loaded with explosives
shall wait or be unloaded in separate safe places away from the loading
operations.
13. Explosives in excess of immediate requirements when removed from
the main storage magazine and delivered in the vicinity of a blasting
operation, shall be stored in a Class II magazine.
14. Caps shall not be brought to the loading area nor attached to the
detonating fuse until all is in readiness to fire the blast.
15. Blast matting (which may include earth) shall be required when blast
operations and/or geological conditions create fly rock that could
damage or injure persons or property.
16. In all blasting operations, except as hereinafter otherwise provided,
the maximum peak particle velocity of any one (1) of three (3) mutually
perpendicular components of the ground motion in the vertical and
horizontal directions shall not exceed one (1) inch per second at
the property line of the blast site. The Director may grant an exception
to the rule when it is not an ongoing blasting operation.
17. Seismographic instrumentation shall be required on any blast site
where the nearest uncontrolled structure or public utility is located
within a scaled distance of sixty-five (65). An uncontrolled structure
is defined as any occupied building not owned or controlled by the
explosives user. The seismograph shall be placed at or near the closest
uncontrolled structure(s).
18. Instrumentation shall be in good operating condition and be properly
calibrated with a current (within one (1) year of date of use) calibration
sticker affixed to each instrument. If an instrument(s) is found to
be not operating properly or out of calibration, blasting operations
shall be halted until the appropriate repairs or recalibration are
performed or a proper instrument(s) is provided. Seismograph operator
shall be trained in the use of that instrument(s).
19. Blasting operations without instrumentation will be considered as
being within the limits set forth in this Subsection if at a specified
location on at least five (5) blasts instrumentation has shown that
the maximum peak particle velocity at the specified location is fifty
percent (50%) or less of the limit set forth in this Subsection, and
with written permission from the Director, provided, that for all
future blasts the scaled distance is equal to or greater than the
scaled distance for the instrumental blast. However, if a scaled distance
less than thirty-five (35) is employed, a seismograph is required
regardless of the seismic readings of previous blasts. "Scaled
distance" means the actual distance in feet divided by the
square root of the maximum explosive weight in pounds that is detonated
per delay period for delay intervals of eight (8) milliseconds or
greater. If delay intervals less than eight (8) milliseconds are employed
or if instantaneous blasting is employed, scaled distance shall be
computed by dividing the actual distance in feet by the square root
of the total explosive weight in pounds. Blasting operations which
would result in ground vibrations that would have a particle velocity
of any one (1) of three (3) mutually perpendicular components in excess
of .30 inches per second and a frequency of less than 20 Hertz at
any uncontrolled structure is prohibited. In addition, blasting is
prohibited below the frequency of 3 Hertz. Blasting at frequencies
of 20 Hertz to 30 Hertz shall not exceed a particle velocity of any
one (1) of three (3) mutually perpendicular components of .50 inches
per second. Blasting at frequencies above 30 Hertz shall not exceed
a particle velocity of any one (1) of three (3) mutually perpendicular
components of .80 inches per second. The Director may grant an exception
to the requirements of this Subsection for blasting operations of
less than thirty (30) days' duration, provided that such operations
do not exceed the following limits at the nearest uncontrolled structure:
a. The maximum peak particle velocity of any one (1) or three (3) mutually
perpendicular components of the ground motion in the vertical and
horizontal directions shall not exceed .50 inches per second for blasts
below 10 Hertz or 1.0 inches per second for blasts from 10 to 30 Hertz
or 1.5 inches per second for blasts above 30 Hertz.
b. The maximum air blast shall not exceed one hundred twenty (120) decibels
at 2 Hertz-flat response and above.
20. Airblast limitations and measurements.
a. Airblast shall be controlled so that it does not exceed the maximum
limit specified below at any uncontrolled structure. Airblast monitoring
equipment shall be used for all blasts at the nearest uncontrolled
structure and records of that monitoring shall be retained for at
least one (1) year for review by and production to the Director.
Lower Frequency Limits of Measuring System, Hz (+ 3dB)
|
Maximum Level in dB
|
---|
2 Hertz or higher—flat response
|
120 peak
|
b. All measuring systems used shall have a flat frequency response of
at least two hundred (200) Hz at the upper end.
21. When blasting in the vicinity of uncontrolled structures the explosives
users will determine the structures lying within a scaled distance
of thirty-five (35). The distance will be determined by the following:
D = 35√W
|
---|
Where D is the distance limit and W is the maximum charge weight
per 8 ms delay interval. The explosives user shall contact the owners
of structures within the distance limit and offer to have a pre-blast
inspection performed on their structure at no cost to the owner.
|
[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §5, 1-28-2004]
Unless otherwise set forth in this Chapter, blasting agents shall be transported, stored and used in the same manner as explosives. Storage of explosives shall comply with the Fire Prevention Code of St. Charles County, Section
500.400, Ordinances of St. Charles County, Missouri, as amended.
[Ord. No. 98-34 §1, 2-25-1998; Ord. No. 04-016 §6, 1-28-2004]
Buildings or other facilities used for mixing blasting agents shall be located, with respect to inhabited buildings, passenger railroads and public highways, in accordance with the Fire Prevention Code of St. Charles County, Section
500.400, Ordinances of St. Charles County, Missouri, as amended.
[Ord. No. 98-34 §1, 2-25-1998]
Persons using blasting agents shall comply with all of the applicable
provisions of this Chapter for the use of explosives.