Hi Margaret – if this person has a disability which means that they can’t hear a traditional smoke alarm, these may be available FOC from local fire service. Certainly Kent Fire & Rescue can (and have in our case) provide one at no cost. And also RNID may provide the same, free of charge. I am not sure how this all applies under the equality act, but as there are options which should come at no cost to the charity, it’s something you would probably want to consider.