Performance Verification of Acoustical Measurement Systems - Technical Guide: Testing standards
Testing standards
Most standards for measurement methods include a statement or paragraph to the effect of:
"Before and after each series of measurements, the calibration of the entire measurement system shall be verified using an acoustical calibrator."
or
"The calibration of the complete sound measuring system, including any recording, data logging, or r.m.s. computing systems, shall be checked immediately before and after the measurement session at one or more frequencies using a sound calibrator."
The user is then referred to a further standard for the calibrator device. More complex measurement systems often require that the filters conform to a particular standard, and that the system be verified as though it were a sound level meter.
The table below attempts to list specification standards relevant to testing particular elements of what may form an acoustical measurement system, and the relation of these to the verification of that instrument. This table is in no way comprehensive, but aims to give guidance on the most commonly used equipment.
| Instrument | Performance requirements | Performance verification | Frequency of verification |
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| Calibrators | BS EN 60942:2003 | Pattern evaluation: BS EN 60942:2003 (Annex A) Periodic testing: BS EN 60942:2003 (Annex B) |
As required* |
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| Filters | BS EN 61260:1996 (supersedes BS 2475:1964) |
Pattern evaluation: BS EN 61260:1996 Periodic testing: BS EN 61260:1996 (Clause 5 & Annex C) |
As required |
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| Instruments for the measurement of aural acoustic admittance | BS EN 61027:1993 | BS EN 61027:1993 | As recommended by the manufacturer |
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| Measurement systems for aeroplane noise certification | BS EN 61265:1995 (supersedes BS 5647:1979) |
Periodic testing: BS EN 61265:1995 (Annex B) | To comply with the national authorities responsible for aircraft noise certification. |
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| Microphones (working standard) | BS EN 61094-4:1996 | BS EN 61094-5:2002 | As required |
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| Personal sound exposure meters | BS EN 61252:1997 (supersedes BS 6402:1993) |
BS EN 61252:1997 Annex B | As recommended by the manufacturer |
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| Recording equipment (analogue and digital) | BS EN 61400-11:1998 | BS EN 60651:1994 (superseded) BS 4847:1989 / IEC 60386:1972 |
Every 2 years |
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| Reference sound sources | BS EN ISO 6926:2001 | BS EN ISO 6926:2001 | At manufacturers recommended intervals |
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| Sound intensity measurement instrument and probe | BS EN 9614-3:2003 | Field check: Procedures 6.2.2 and 6.2.3 of BS EN 9614-3:2003 | Prior to each series of measurements |
| " " | BS EN 61043:1993 | Periodic testing: BS EN 61043:1993 (Annex A) |
Every 1 year (or every 2 years if used with an intensity calibrator prior to each measurement) |
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| Sound level meters | BS EN 61672-1:2003 (supersedes BS EN 60651:1994 and BS EN 60804:2001) |
Pattern evaluation: BS EN 61672-2:2003 (supersedes BS EN 60651:1994 and BS EN 60804:2001) Periodic testing: BS EN/IEC 61672-3 (in preparation) |
As required |
| " " | BS EN 60651:1994 (superseded) (formerly BS 5969:1981 identical to IEC 60651:1979) |
Pattern evaluation: BS EN 60651:1994 (superseded) Periodic testing: BS 7580:Part 1:1997 |
As required |
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| Sound level meters (Type 2) | BS EN 60651:1994 (superseded) | Pattern evaluation: BS EN 60651:1994 (superseded) Periodic testing: BS 7580-2:1997 |
As required |
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| Sound level meters (integrating-averaging) | BS EN 61672-1:2003 (supersedes BS EN 60651:1994 and BS EN 60804:2001) |
Pattern evaluation: BS EN 61672-2:2003 (supersedes BS EN 60651:1994 and BS EN 60804:2001) Periodic testing: BS EN/IEC 61672-3 (in preparation) |
As required |
| " " | BS EN 60804:2001 (superseded) (formerly BS 6698:1986) |
Pattern evaluation: BS EN 60804:2001 (superseded) Periodic testing: BS 7580:Part 1:1997 |
As required |
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| Sound level meters (integrating-averaging Type 2) | BS EN 60804:2001 (superseded) | Pattern evaluation: BS EN 60804:2001 (superseded) Periodic testing: BS 7580-2:1997 |
As required |
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| Sound level meters for the measurement of motor vehicle noise | BS 3539:1986 | Periodic testing: BS 7580:Part 1:1997 & 2.1 to 2.4 of BS 3539:1986 | Annually |
*As required by other measurement standard