a housing company, will also use them as alternative accomodation for people like nurses on call.

hi what is the meaning of alternative accomodation?
Hello, you've been reading about the buses being converted into hostel style housing units haven't you...

It means that they are not really housing as such, but can provide accomodation for people.(In the example given, nurses on call, the nurses can be to hand in the hospital car park, so can respond to an emergency quickly during their 'on-call' shift, but still get some sleep and relax when they are not needed).
yes:d you are right:p

thanks ,i underestand now:)