Answer:
All of the following words appear in the Official Scrabble Players Dictionary, 4th Edition, except those with asterisks (*), which appear in the Official Tournament and Club Word List, 2nd Edition, and those with double asterisks (**), which appear in the Official Long Words List.
AIRPROOF
ALOOF
BABYPROOF *
BEHOOF
BOMBPROOF *
BULLETPROOF **
BURGLARPROOF **
CHILDPROOF **
CRUSHPROOF **
COOF
DISPROOF
DUSTPROOF *
FIREPROOF *
FLAMEPROOF **
FOOLPROOF *
FOREHOOF
GANOF
GERMPROOF *
GONOF
GOOF
GREASEPROOF **
HEATPROOF *
HEREOF
HOOF
KLOOF
LEAKPROOF *
LIGHTPROOF **
LOOF
MOONROOF
MOTHPROOF *
OF
OILPROOF
OVENPROOF *
OVERPROOF *
PICKPROOF *
PILFERPROOF **
POOF
PROF
PROOF
RAINPROOF *
REPROOF
ROOF
RUSTPROOF *
SHADOOF
SHATTERPROOF **
SHELLPROOF **
SHOCKPROOF **
SKIDPROOF *
SOUNDPROOF **
SPOOF
STAINPROOF **
SUNPROOF
TAMPERPROOF **
UNDERPROOF **
UNROOF
WATERPROOF **
WEARPROOF *
WEATHERPROOF **
WETPROOF
WHEREOF
WHOOF
WINDPROOF *
WITLOOF
WOOF