dB (A) : A-weighted decibel. The A-weighting is that specified in the International Standard IEC 60651. A-frequency weighting is used because it approximates the response of the human ear
Ministry of Business, Innovation and Employment, Glossary of terms and acronyms, Wellington, New Zealand 2010. http://wwwsosh.govt.nz/resources/glossary-u.shtml, (Occupn Hlth and Sfty - Brit) {530}