With a little care climbing harnesses will last longer and perform better.
Always store climbing harnesses in a cool dry place away from solvents and sunlight. Nylon is especially susceptible to U.V. rays.
Wash a harness with warm water and a little mild detergent when needed. Rinse and let hang to dry.
Never expose nylon climbing harnesses to high heat sources. These can prematurely break down the fibres in the nylon.