1:3 Octave Band Filters |
Single 1:1 Octave bands divided into three parts. |
1:1 Octave Band Filters |
A division of the frequency range into bands, the upper frequency limit of each band being twice the lower frequency limit. |
A Weighting |
A standard weighting of the audible frequencies designed to reflect the response of the human ear to noise. |
Acoustic Calibrator |
An instrument that provides a reference noise source that is used to calibrate and check the performance of a Sound Level Meter. |
Broadband |
Noise Measurements using parameters which include all the audible noise, such as dB(A) and dB(C) |
C Weighting |
A standard weighting of the audible frequencies used for the measurement of Peak Sound Pressure level. |
CE Marking |
A label used to show that the Sound Level Meter conforms to the specification of a European Directive |
Data Logging |
Measurements can be stored in the Sound Level Meter for download to a PC |
dB(A) |
Decibels A weighted |
dB(C) |
Decibels C Weighted |
dB(Z) |
Decibels Z weighted |
Decibel (dB) |
The units of sound level and noise exposure measurement |
DIN 45641 |
German Standard which defines the additional measurements LAFTeq & LIeqT |
% Dose |
The noise exposure expressed as a percentage (%) of a fixed level for 8 hours |
Exposure |
Noise Exposure in Pa2h (Pascal Squared Hours) |
Fast Time Weighting |
A standard time weighting applied by the Sound Level Meter |
IEC 60804:1984 |
The International Standard for Integrating & Integrating-Averaging Sound Level Meters |
IEC 61672:2002 |
The International standard for Sound Level Meter and Integrating Averaging Sound Level Meters has superseded both IEC 60651 and IEC 60804 |
IEC 60651:1979 |
The International Standard for Sound Level Meters |
IEC 61260:1995 |
The International Standard for 1:1 Octave & 1:3 Octave Band Filters |
Impulse Time Weighting |
A standard time weighting applied by the Sound Level Meter |
Integrating Averaging Sound Level Meter |
A Sound Level Meter which accumulates the total sound energy over a measurement period and calculates an average |
LA10 |
The noise level exceeded for 10% of the measurement period with 'A' frequency weighting calculated by statistical analysis |
LA90 |
The noise level exceeded for 90% of the measurement period with 'A' frequency weighting calculated by statistical analysis |
LAE |
Sound Exposure Level (SEL) with 'A' frequency weighting |
LAeq,t |
Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'A' weighting. |
LAF |
Sound level with 'A' Frequency weighting and Fast Time weighting |
LAFmax |
The maximum Sound level with 'A' Frequency weighting and Fast Time weighting |
LAFTeq |
Takt maximal sound level as defined by DIN 45641 |
LAI |
Sound level with 'A' Frequency weighting and Impulse Time weighting |
LAImax |
The maximum Sound level with 'A' Frequency weighting and Impulse Time weighting |
LAS |
Sound level with 'A' Frequency weighting and Slow Time weighting |
LASmax |
The maximum Sound level with 'A' Frequency weighting and Slow Time weighting |
LCE |
Sound Exposure Level (SEL) with 'C' frequency weighting |
Lceq,t |
Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'C' weighting. |
LCF |
Sound level with 'C' Frequency weighting and Fast Time weighting |
LCFmax |
The maximum Sound level with 'C' Frequency weighting and Fast Time weighting |
LCI |
Sound level with 'C' Frequency weighting and Impulse Time weighting |
LCImax |
The maximum Sound level with 'C' Frequency weighting and Impulse Time weighting |
LCpeak |
Peak Sound pressure level with 'C' frequency weighting |
LCS |
Sound level with 'C' Frequency weighting and Slow Time weighting |
LCSmax |
The maximum Sound level with 'C' Frequency weighting and Slow Time weighting |
LEP,d |
Daily personal noise exposure |
Leq |
Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB |
LIeqT |
Impulse weighted Leq,t as defined by DIN 45641 |
Ln |
Statistical analysis of noise levels. The n denotes the percentage exceedence. |
LZE |
Sound Exposure Level (SEL) with 'Z' frequency weighting |
LZeq,t |
Equivalent continuous sound pressure level. A measure of the average sound pressure level during a period of time, t, in dB with 'Z' weighting. |
LZF |
Sound level with 'Z' Frequency weighting and Fast Time weighting |
LZFmax |
The maximum Sound level with 'Z' Frequency weighting and Fast Time weighting |
LZI |
Sound level with 'Z' Frequency weighting and Impulse Time weighting |
LZImax |
The maximum Sound level with 'Z' Frequency weighting and Impulse Time weighting |
LZS |
Sound level with 'Z' Frequency weighting and Slow Time weighting |
LZSmax |
The maximum Sound level with 'Z' Frequency weighting and Slow Time weighting |
Overload |
The input to the Sound Level Meter is too high for the current measurement range. Change the range |
Peak |
The maximum value reached by the sound pressure at any instant during a measurement period (in dB usually with C frequency weighting) |
SEL |
Sound Exposure Level, displayed as LAE, LCE or LZE |
Slow Time Weighting |
A standard time weighting applied by the Sound Level Meter |
Sound Level |
Sound Pressure Level with a Frequency weighting, such as dB(A) |
Sound Level Meter |
An instrument for measuring various noise parameters |
SPL |
Sound Pressure Level, the basic measure of noise level, expressed in decibels |
Statistical Analysis |
A calculation performed by a Sound Level Meter on the noise levels measured during the measurement period to describe the statistical spread of the noise. |
Type 2 |
General Field Grade for Sound Level Meter |
Type 1 |
Laboratory & Field Grade for Sound Level Meters |
Under Range |
The input to the Sound Level Meter is too low for the current measurement range. Change the range |
Z Weighting |
Z weighting is a flat frequency response between 10Hz and 20kHz ±1.5dB excluding microphone response. |