Electric blankets.

[Amp David]

Just fit some rubber legs to the bed

 

[La Poste]

How about fitting a special socket with an isolating transformer in it, you know like a shaver socket but 230V and just for the electric blanket.
Apparently that's how they do stuff in hospitals. To make the electrical apparatus safe for use near a patient having an operation a lot of special sockets are fitted that are isolated from the main installation by use of transformers, that way there is no way the patient can get an electric shock.
Does this sound right?
So we have a bed on rubber legs with an isolating transformer as a socket and a smoke alarm above, my old dad couldn't be safer.
I'm not sure about the strobe though, I'm sure it's a joke, maybe have disco lights and a siren aswell.

 

[Garethcnmjones]

If your blanket has instruction on it then just follow them otherwise dont let your uncle use it but you are taking some safety precaution steps that is even better.