SCIENCE|natural and applied sciences|earth sciences
- leibhéal torainn in aghaidh na huaire Reference Faomhadh an téarma seo mar chuid de Thionscadal Lex
- ga
- HNL | hourly noise level
- en
- Definition the average A-level(derived on an energy basis)which exceeds a threshold noise level and is integrated over a time period of one hour Reference Multilingual Aeronautical Dictionary(AGARD,1980)