Occupational exposure to noise from authorized emergency vehicle sirens.

Warning signals generated by sirens of authorized emergency vehicles should be audible and recognizable to all road users. Currently, there is no legislation in Poland defining sound pressure levels (SPLs) of audible warning signals generated by sirens of authorized emergency vehicles. Measured A-weighted SPLs of those signals range between 104 and 108 dB. While for road users, an audible warning signal is a source of important information and its A-weighted SPL is acceptable, it may be a source of annoying noise to an emergency vehicle crew. That is why, it is necessary to find a method of improving the acoustic comfort of the crew and, at the same time, maintaining the informational function of audible warning signals.