Spartan 821/721 Manual Glossary C-13
Projected Daily Personal Noise Exposure
(P.L
EP,d
or P.L
EX
,8h)The Daily Personal Noise Exposure assuming that the current rate of
noise dose exposure continues for the duration of a work shift (Shift Time). For example,
a measured L
eq
of 86 dB with a Run Time of 4 hours will produce a L
EP,d
or L
EX
,8h or 83
dB, but a projected P.L
EP,d
or P.L
EX
,8h of 86 dB if the Shift Time is 8 hours. If the shift time
is doubled (16 hours), the P.L
EP,d
or P.L
EX
,8h would become 89 dB.
Projected Noise Dose
Projected Noise Dose is the Noise Dose assuming that the current rate of noise exposure
continues for the full duration of an 8 hour work shift. Displays on the dosimeter LCD as
P. Dose.
OR
OR
P.LEP,d or P.LEX,8h L
eq
10+ log
10
T
S
T
n
------
dB
=
L
eq
= frequency weighted (A or C), equivalent-continuous sound pressure level in dB
T
n
= normalization period or Criterion Duration (8 hours)
T
S
= work shift duration, Shift Time
P.Dose
T
S
T
------
100
T
C
---------
10
L
AS
L
C
–
q
---------------------
td
T
1
T
2
%=
P.Dose 100
T
S
T
------
10
L
avg
L
C
–
q
----------------------
%=
P.Dose Dose
T
S
T
C
-------
%
=
L
AS
= A-weighting frequency and slow-exponential
weighting time sound level in dB (in the formula
above, if the sound level is less than the user
specified threshold level, then L
AS
= -∞)
L
avg
= average sound level in dB, only recording
values higher than the user specified threshold
level
L
C
= Criterion Level in dB
T = measurement period or Run Time (T = T
2
– T
1
)
T
S
= work shift duration, Shift Time
T
C
= Criterion Duration in hours (8 hours)
q = exchange rate constant
• if exchange rate = 3, q = 10
• If exchange rate = 4, q = 4 / log
10
(2) ≈ 13.29
• If exchange rate = 5, q = 5 / log
10
(2) ≈ 16.61
• If exchange rate = 6, q = 20
To Next Page
Loading...
