Traction tests were done in several kinds of footwear (dinghy boots are shown here) with panels inclined at 45°. An old pair of deck shoes with worn soles was used to consolidate the ratings.

Some of the most frequent questions we receive from readers involve what to do about old decks—how to clean them, repair them, or completely refurbish them. Usually these decks are fiberglass, with molded-in non-skid surfaces that are worn down to the point where they offer minimal traction, or are scrubbed right through to the pink fiberglass below the gelcoat, or crazed with hairline cracks, or just plain stained and dirty.

We've looked at this subject often, most recently about a year and a half ago, in the February 1, 2003 issue, when we covered eight paint additives and two mats. For those evaluations, we were careful to match non-skid additives with…