For any given substance, the heat capacity of a body is directly proportional to the amount of substance it contains (measured in terms of mass or moles or volume). Doubling the amount of substance in a body doubles its heat capacity, etc.
Conventional soft contacts can last up to a year; conventional rigid gas permeable (RGP) contact lenses can last even longer. Frequent or planned replacement contact lenses last one to several months. Disposable contacts last from one day (daily wear) to up to two weeks (extended wear).
If you wear contact lenses you must stop wearing them prior to surgeryâat least two weeks for soft contacts and one month for hard contacts. This is because contact lenses can cause mild warping of the corneal shape, which may interfere with the preoperative measurements of the eye and calculations for RLE surgery.