Are they machine washable?
Yes. S&L Gel Manicure UV Gloves are reusable. Hand wash or machine wash in warm water with a mild detergent, rinse thoroughly, and dry flat away from direct heat.
The UV protection comes from the fabric itself rather than a surface treatment (ie. Titanium Dioxide), so ordinary washing does not remove it, but stretching, snagging, and abrasion will thin the weave over time, and thinner fabric lets more UV through.
When to wash them. Filing dust, cuticle oil, and hand cream build up in the weave and can make the fabric stiff. Washing every few manicures is enough for home and salon use.
If gel gets on the glove (this is the important one). Wipe the spot immediately with a lint-free wipe and 99% isopropyl alcohol, before it goes anywhere near the lamp. If the gel has soaked through to your skin, take the glove off and wash your hands before continuing.