Maybe they are having a "dry clean" as my Grandmother would call it.
She used to have one of those medic alert buttons around her neck that you press in case of an emergency. One day my mother got a call to say the alarm had been activated. When my Mum let herself into my grandmothers house she could hear giggles coming from the end of the house she found my grandmother sitting fully clothed in the bath, laughter tears streaming down her cheeks... she had hoped into the bath with her clothes on to make sure she could get out before she went in naked... well she couldn't get out. She said she was having a dry clean. I do miss her.