<![CDATA[Ïã¸ÛÁùºÏ²Ê¿ª½± 454:1975]]> /cms/render/live/en/sites/isoorg/contents/data/standard/00/44/4476.html Ïã¸ÛÁùºÏ²Ê¿ª½± standards and projects Ïã¸ÛÁùºÏ²Ê¿ª½±.org 60 /modules/isoorg-template/img/iso/favicon/red/favicon1.ico http://www.iso.org/ <![CDATA[Ïã¸ÛÁùºÏ²Ê¿ª½± 454:1975]]> <![CDATA[Ïã¸ÛÁùºÏ²Ê¿ª½± 454:1975 - Acoustics — Relation between sound pressure levels of narrow bands of noise in a diffuse field and in a frontally-incident free field for equal loudness]]> /cms/render/live/en/sites/isoorg/contents/data/standard/00/44/4476.html /cms/render/live/en/sites/isoorg/contents/data/standard/00/44/4476.html 1987-05-01