§ 193-9. Vibration and concussion standards.

A. 

The maximum allowable concussion or air blast resulting from blast operations shall not exceed 130 decibels peak, measured at a flat frequency response (PMS two decibels) over the range of at least six hertz to 200 hertz.

B. 

When blasting is of a continuing nature, 124 decibels to 130 decibels shall be the acceptable range.

C. 

The permit holder shall report each blast exceeding acceptable parameters to the Building Inspector within 24 hours. Following a blast exceeding acceptable parameters, the Building Inspector shall have the authority to order blasting operations to be suspended, altered or stopped.

D. 

When no instrument is used to measure the seismic effect of a blast, the maximum amount of explosives detonated shall not exceed the limits shown in the following table:

[Amended 1-22-2013 by L.L. No. 1-2013]

	Table 1
	Distance Versus Weight of Explosives Method*
	Distance to Nearest Building (feet)	Number of Pounds per Delay	Distance to Nearest Building (feet)	Number of Pounds per Delay
	0 to 5	1/4	More than 250 to 260	45
	More than 5 to 10	1/2	More than 260 to 280	49
	More than 10 to 15	3/4	More than 280 to 300	55
	More than 15 to 60	0.1 per foot D	More than 300 to 325	61
	More than 60 to 70	6	More than 325 to 350	69
	More than 70 to 80	7 1/4	More than 350 to 375	79
	More than 80 to 90	9	More than 375 to 400	85
	More than 90 to 100	10 1/2	More than 400 to 450	98
	More than 100 to 110	12	More than 450 to 500	115
	More than 110 to 120	13 3/4	More than 500 to 550	135
	More than 120 to 130	15 1/2	More than 550 to 600	155
	More than 130 to 140	17 1/2	More than 600 to 650	175
	More than 140 to 150	19 1/2	More than 650 to 700	195
	More than 150 to 160	21 1/2	More than 700 to 750	220
	More than 160 to 170	23 1/4	More than 750 to 800	240
	More than 170 to 180	25	More than 800 to 850	263
	More than 180 to 190	28	More than 850 to 900	288
	More than 190 to 200	30 1/2	More than 900 to 950	313
	More than 200 to 220	34	More than 950 to 1,000	340
	More than 220 to 240	39	More than 1,000 to 1,100	375
	More than 240 to 250	42	More than 1,100 to 1,200	435
			More than 1,200 to 1,300	493

	NOTE:
	*	Distances over 60 feet are based on the formula W = D x 1.5/90, where W = weight and D = distance.

E. 

When an instrument is used to measure the seismic effect of a blast, the maximum peak particle velocity on any one component of an instrument measuring three-component motion shall not exceed the limits of the following table:

[Amended 1-22-2013 by L.L. No. 1-2013]

	Table 2
	Distance Versus Peak Particle Velocity Method
	Distance (feet)	Peak Particle Velocity of any One Component* (inches per second)
	0 to 100	1.50
	More than 100 to 200	1.25
	More than 200 to 500	1.00
	More than 500 to 1,000	0.50
	Over 1,000	0.25

	NOTE:
	*	The measuring instrument's transducer shall be firmly coupled to the ground.