This is a non-standard tag, with only 6 uses so far. It should not be documented in Map Features wiki pages. To make it even worse, its meaning overlaps with military=range.
Its definition also does not consider that there are many shades of exclusion. There are areas where trespassing is always forbidden and there are big fences and cameras around (e.g. on Kohlreithberg), but there are also areas where trespassing is forbidden but there is no fence or surveillance (e.g. Truppenübungsplatz Allentsteig), and there are areas where access is permitted on many tracks outside the shooting times (e.g. Truppenübungsplatz Bruckneudorf). --Fkv (talk) 21:13, 21 December 2013 (UTC)
military=* tags generally specify the use of a military feature, not its permissions. If you want to specify that an area is an exclusion zone, set access=no. --Fkv (talk) 21:53, 21 December 2013 (UTC)