▁particularly ▁useful ▁in ▁areas ▁that ▁have ▁become ▁a ▁dead ▁zone ▁due ▁to ▁e ut roph ic ation . ▁▁ ▁Air ▁cur tain s ▁may ▁have ▁another ▁application . ▁Dol ph in ▁and ▁wh ale ▁be aching ▁has ▁increased ▁with ▁the ▁rise ▁in ▁ocean ▁temper atures . ▁On ▁Th urs day ▁February ▁ 1 2 th , ▁ 2 0 1 7 , ▁a ▁group ▁of ▁nearly ▁ 4 0 0 ▁wh ales ▁be ached ▁near ▁Golden ▁Bay ▁on ▁the ▁tip ▁of ▁New ▁Zealand ’ s ▁South ▁Island , ▁following ▁a ▁similar ▁incident ▁earlier ▁that ▁week . ▁The ▁simplicity ▁of ▁an ▁air ▁cur tain ▁system , ▁requiring ▁only ▁air ▁compress ors ▁and ▁per for ated ▁h oses , ▁could ▁allow ▁for ▁rapid ▁deployment ▁and ▁create ▁aer ated ▁zones ▁of ▁o xygen ated ▁se aw ater ▁during ▁a ▁marine ▁emer gency . ▁ ▁Air ▁cur tain s ▁are ▁also ▁used ▁to ▁control ▁the ▁release ▁of ▁smoke ▁particles ▁into ▁the ▁environment . ▁After ▁a ▁natural ▁dis aster , ▁or ▁during ▁br ush ▁clear ing ▁activities , ▁de br is ▁is ▁dis posed ▁of ▁by ▁inc iner ation ▁in ▁either ▁a ▁cer am ic ▁or ▁earth ▁pit ▁contain ment . ▁Similar ▁to ▁an ▁air ▁cur tain ▁to ▁separate ▁ind oor ▁air ▁from ▁out door ▁air , ▁for ▁instance ▁in ▁restaur ants ▁and ▁walk - in ▁re fr iger ators , ▁a ▁powerful ▁air ▁cur tain ▁can ▁defeat ▁the ▁chim ney ▁effect ▁of ▁the ▁inc iner ation ▁process ▁to ▁eliminate ▁any ▁smoke ▁from ▁a ▁br ush ▁inc iner