What is the allowable noise exposure for one hour a day?

Answer 1

"Permitted Exposure Time Guidelines - SPL"

Sound pressure level Lp and permissible exposure time t:

115 dB = 0.46875 minutes (~30 sec)

112 dB = 0.9375 minutes (~1 min)

109 dB = 1.875 minutes (< 2 min)

106 dB = 3.75 minutes (< 4 min)

103 dB = 7.5 minutes

100 dB = 15 minutes

97 dB = 30 minutes

94 dB = 1 hour

91 dB = 2 hours

88 dB = 4 hours

85 dB = 8 hours

82 dB = 16 hours

Lower dBs are said to be harmless