Which of the following noise levels indicates hazardous impulse noise?

Hazardous impulse noise is characterized by its sudden and extremely loud sounds, which can lead to immediate damage to hearing. The unit 'decibel' (dB) measures sound levels, while 'A' and 'C' weighting refer to different ways of measuring sound that relate to how humans perceive sound frequencies.

A decibel level of 140 dBP represents a very intense sound and is recognized as hazardous because it is significantly above levels that are generally safe for hearing. Impulse noise at this level can result in immediate and permanent hearing loss due to the high sound pressure levels that can exceed the threshold of pain.

To provide context, the other options indicate noise levels that, while potentially harmful with prolonged exposure, do not reach the critical intensity associated with impulse noise that can cause instant damage. For instance, a level of 70 dBP is below the threshold for concern in terms of impulse noise, while 84 dBA and 100 dBA, although they can be harmful over time, typically do not reach the instantaneous risk level associated with hazardous impulse noise.