Strategic noise map of type A according to the indicator Ln (night) of the network referred to in Loire-Atlantique

Map of type “a” delimiting, by level d'isophone at the footstep of 5 dB(A), areas exposed to noise in Ln, noise indicator at night, from 50 dB(A) to 70 dB(A) — Referred network — stopped on 11/12/2018 Noise zones are geometrical elements of the strategic noise map. For Type A cards (CBSTYPE), each noise zone is usually bounded by 2 isophone curves (Lden 55-60, 60-65, 65-70, 70-75 and Ln 50-55, 55-60, 60-65, 65-70) or shares the lower limit isophone curve (Lden >75, Ln > 70). For C-type maps (CBSTYPE), each noise zone is delimited by the lower limit isophone curve (Lden > 68 or 73, Ln > 62 or 65). __Origin__ BD Carto. Each municipality informed about 4 types of ' challenges (water pollution by phytos, l' soil erosion, biodiversity and reduction of water withdrawals). __Partner organisations__ DDTM Loire-Atlantique [See this page on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/9d047f2fec365959abb6dbd87f2da399c5734253)