Table 1. Source characteristics of the airgun operated at different combinations of pressure and volume.

	10 in3 airgun		25 in3 airgun		40 in3 airgun
	low	high	low	high	low	high
D-duration (ms)	19	20	40	21	48	21
	38	20	76	20	50	21
	84	18	78	53	49	21
	167	19	76	100	48	21
L pp (dB re 1μPa)	180	182	178	184	182	187
	179	183	179	183	182	188
	178	183	178	184	182	188
	176	182	179	184	182	188
						188
L eq-fast (dB re 1μPa)	161	161	159	163	162	167
	160	162	160	163	162	167
	160	161	160	164	162	167
	159	161	160	165	162	168
						168
SEL (dB re 1μPa 2 s)	152	152	151	154	153	159
	153	153	151	155	154	160
	153	152	151	155	153	159
	152	153	151	156	153	159
						159
f peak (Hz)	34	113	89	6	6	39
	36	113	90	46	5	40
	38	5	90	42	79	40
	39	5	90	8	79	40
						40
BW -3dB (Hz)	3	111	86	41	103	3
	3	7	56	5	0	4
	3	110	86	3	3	4
	3	3	57	84	3	4
						5
BW -10dB (Hz)	64	211	172	152	185	47
	36	206	173	150	101	151
	39	240	146	178	154	152
	8	160	170	152	154	120
						154

Unweighted values are given for 4–5 recordings of airgun pulses for different combinations of airgun volume and output pressure obtained at a range of 120 m from the airgun.