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COMPTUEX/JTFEX EA/OEA Final Chapter 4lung injury. These are considered indicative of the onset of injury. The threshold for TM rupturecorresponds to a 50 percent rate of rupture (i.e., 50 percent of animals exposed to the level are expected tosuffer TM rupture); this is stated in terms of an EFD value of 1.17 in-lb/in 2 , which is about 205 dB re 1Pa 2 -s. This recognizes that TM rupture is not necessarily a life-threatening injury, but is a useful indexof possible injury that is well-correlated with measures of permanent hearing impairment (e.g., Ketten(1998) indicates a 30 percent incidence of permanent threshold shift (PTS) at the same threshold). Athreshold level of 13 psi-ms has been established as an indicator of onset of slight lung injury, the secondcriteria used to indicate non-lethal injurious impacts. Harassment levels are shown in Table 4.3.4.Table 4.3-4. Underwater Detonations – Pinnipeds and CetaceansLethality Level A Harassment Level B HarassmentOnset of extensive lunginjuryInjurious;tympanicmembrane ruptureOnset of slight lunginjuryNon-injurious;onset temporary threshold shift (TTS)30/5 psi-ms at the surface 205 dB re1 Pa 2 -s** Note: In greatest 1/3-octave band above 10 Hz or 100 Hz13 psi-ms at thesurface182 dB re 1 Pa 2 -s1/3 max. octave band >100Hz for toothed and>10Hz for mysticetes and 23 psiEndangered Species ActPotential for injury constituting harm under the ESA—ESA regulations define harm as “an act whichactually kills or injures” fish or wildlife (50 CFR § 222.102). Based on this definition, the criterionapplied here is PTS, a permanent noise-induced hearing loss. PTS is non-recoverable and as definedwithin this analysis, must result from the destruction of tissues within the auditory system. In thisanalysis, the smallest amount of PTS (onset-PTS) is taken to be the indicator for the smallest degree ofinjury that can be measured. The acoustic exposure associated with onset-PTS (EL of 215 dB re 1 μPa 2 -sor greater) is used to define the outer limit of the zone within which listed species are considered topotentially experience harm.Potential for non-injurious physiological effects constituting harassment under the ESA—ESAregulations define harassment as an “intentional or negligent act or omission which creates the likelihoodof injury to wildlife by annoying it to such an extent as to significantly disrupt normal behavioral patternswhich include, but are not limited to, breeding, feeding, or sheltering” (50 CFR § 17.3). In thisassessment, the smallest measurable amount of TTS, onset-TTS, is taken as the best indicator for slighttemporary sensory impairment. TTS is recoverable and, as in recent rulings (NOAA 2001; 2002), isconsidered to result from the temporary, non-injurious distortion of hearing-related tissues. Because it isconsidered non-injurious, the acoustic exposure associated with onset-TTS (EL greater than or equal to195 dB re 1 μPa 2 -s) is used to define the outer limit of the zone within which listed species are predictedto experience harassment attributable to physiological effects. This follows from the concept that eventemporary hearing loss at a single frequency potentially affects an animal’s ability to react normally to thesounds around it.Potential for behavioral effects without physiological effects constituting harassment under the ESA—Acoustic exposure may result in behavioral effects that exceed the normal daily variation in behavior, butwhich arise without an accompanying physiological effect. In this assessment, these effects are alsoconsidered “harassment” under the ESA. This “zone” extends to a point at which no significant disruptionin normal behavioral patterns occurs. The acoustic exposure of EL greater than or equal to 190 dB re 14-25 February 2007