also sometimes called « protection antiaérienne » (see http://w3public.ville-ge.ch/seg/xmlarchives.nsf/Attachments/...$file/protection_civileISAARframeset.htm?OpenElement).

when I your question I originally thought this had something to do with an « abri atomique », but I couldn't figure out where the P came into it, and internet searches turned up nothing. Further research came up with this, which I'm convinced is the right answer. Seems to be quite specific to Switzerland - nearly all search results answers are located in Switzerland.

see also

Bâtiments publics. \ Abris Protection Aérienne (P.A.)
http://www.panorama.vd.ch/detail.aspx?ID=155178


Domain Defence, Administrative law
fr
Term Office fédéral des troupes de protection aérienne
Reliability 3 (Reliable)
Term Ref. (a)Armée suisse,Offices militaires(51.74 dfi),1996;LF Organisation de l'administration fédérale,art.58 al.1 let.c(RO 1979 132);(b)ACF Service de la protection aérienne passive,ch.1(FOM 1936 125);(c)LF Organisation militaire,art.167 al.1(RO 1945 425);(d)LF Organisation militaire,art.171 al.1(RO 1952 331)
Regional Usage CH
Date 24/09/2003

Abbreviation OFTPA
Reliability 3 (Reliable)
Term Ref. (a)Armée suisse,Offices militaires(51.74 dfi),1996;LF Organisation de l'administration fédérale,art.58 al.1 let.c(RO 1979 132);(b)ACF Service de la protection aérienne passive,ch.1(FOM 1936 125);(c)LF Organisation militaire,art.167 al.1(RO 1945 425);(d)LF Organisation militaire,art.171 al.1(RO 1952 331)
Regional Usage CH
http://iate.europa.eu/SearchByQuery.do?method=searchDetail&l...