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tatives at the WG 28 meeting (Jeff Schmitt and Brad Moulton), and other countries represented were: Canada, France, Germany, Japan, Republic of Korea, and Sweden. (see Fig. 1) The standards under discussion included:
• ISO 3744 Acoustics—Determination of sound power levels and sound energy levels of noise sources using sound pressure—Engineering methods in an essential- ly free field over a reflecting plane,
• ISO 3745 Acoustics—Determination of sound power levels of noise sources using sound pressure— Precision methods for anechoic rooms and hemi-ane- choic rooms,
• ISO 6926 Acoustics—Requirements for the perform- ance and calibration of reference sound sources used for the determination of sound power levels,
• ISO 3740 Acoustics—Determination of sound power levels of noise sources—Guidelines for the use of basic standards,
• ISO 11200 Acoustics—Noise emitted by machinery and equipment – Guidelines for the use of basic stan- dards for the determination of emission sound pres- sure levels at a work station and at other specified posit- ions,
• ISO 11201 Acoustics—Noise emitted by machinery and equipment—Determination of emission sound pressure levels at a work station and at other specified positions in an essentially free field over a reflecting plane with negligible environmental corrections, and
• ISO 11202 Acoustics—Noise emitted by machinery and equipment—Determination of emission sound pressure levels at a work station and at other specified positions applying approximate environmental correc- tions.
The ISO 3740 series of sound power standards and ISO 6926 are of particular importance to the ASA Accredited Standards Committee S12 (Noise) since the current versions have been nationally adopted as the ANSI/ASA S12.5x series and ANSI/ASA S12.5, respectively.
In addition the ISO/TC 43/SC 1 Secretariat asked WG 28 for a recommendation on the recent systematic review of sev- eral ISO Standards, for which the United States and two other countries had recommended revision:
• ISO7574-1,-2,-3,and-4(Statisticalmethodsfordeter- mining and verifying stated noise emission values of machinery and equipment) and
• ISO 11689 (Procedure for the comparison of noise- emission data for machinery and equipment).
The ISO Central Secretariat requested that ISO/TC 43/SC 1 delete preliminary work items (PWI) in WG 28 which had not been active, and ISO/TC 43/SC 1 asked WG 28 for a recommendation on:
• PWI 4871 (Declaration and verification of noise emis- sion values of machinery and equipment)
• PWIs 9614-1, -2, -3 (Determination of sound power levels of noise sources using sound intensity)
ISO 3744: Although not in attendance, WG 28 member Patrick Kurtz from Germany sent a letter to WG 28 urging
that the standard be simplified since it was unnecessarily complex for manufacturers to use and as a result manufac- turers were using other less precise methods. Kurtz especial- ly mentioned the uncertainty and background noise correc- tion sections. All members agreed to the need for a simplified version, and WG 28 formed an ad hoc project team to start a revision immediately to simplify ISO 3744 – the project co- leaders will be Kurtz and Jean Jacques from France. Jeff Schmitt raised several issues with the current standard espe- cially on the environmental correction K2, and it was clari- fied that it was intentional that there was no restriction on K2 in frequency bands but only on A-weighted K2.
Amendment to ISO 3745 Annex A on room qualifica- tions. WG 28 resolved comments received from WG 28 members on the proposed amendment to Annex A, which will incorporate provisions in the newly adopted ISO 26101:2012 on anechoic room qualifications. At its meeting, ISO/TC 43/SC 1 approved a ballot for a new work item pro- posal for the proposed amendment. Jeff Schmitt suggested that it should be possible to use a draw away test to determine which portions of a room meet precision grade, engineering grade and then survey grade.
WG 28 recommended that TC 43 not disband WG 8 (Test methods for the qualification of free-field environ- ments) as planned. WG 28 supported the proposal raised by
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