In sheltered (or community supportive) accommodation there is often a property manager or scheme manager who lives on site. They will visit or call residents from time to time to make sure that they are well and comfortable, will address any concerns which they may have and offer advice, and can put them in touch with additional support when required.
In some accommodation there is not a manager living on site, but a locally-based team will regularly call on and check residents to make sure that they are okay.
Residents will also be provided with an alarm system so that they can call for help in an emergency at any time of the day or night - the scheme manager (or off-site team) will be the person who usually responds to an alarm call.
In some areas the council will arrange for this off-site checking service to take place in a person's own home so that they don't have to move to specialist sheltered housing. As with sheltered accommodation residents will be provided with an alarm system to call for help in an emergency.