Hubby has a concentrator kept in dining room. Dining room now known as equipment room with this, cylinders, wheelchair,walker, bits and bobs, nebuliser etc. We haven't used it for months and a quick dust and Hoover is the most I have done. Found some bits on floor a few days ago and then some more. The chairs nearest the concentrator have leather backs and seats and this has dried up and split. It is not the heat I don't think because we have other chairs close to a storage radiator with no problems over many years. Just yet another thing to be aware of!