Public Address (PA) systems in buildings like airports, railway
stations, shopping centers, stadiums, or concert halls have to clearly
inform persons in danger about escape information and directions in case
of an emergency. People need to be given clear instructions so they can
react quickly and in an orderly fashion - a Life Safety Code
requirement.
Using a hand-held instrument, it is possible to commission the entire
building by measuring just how intelligible the PA announcements will
be when comprehensibility is most needed.