This specification covers requirements for wooden derricks@ including stipulation on materials@ design features@ loadings@ and allowable stresses. Recommendation on safe load capacities for wooden derricks are included as an appendix. Nothing contained in this specification is to be contained in this specification is to be construed as granting right@ by implication or otherwise for manufacture@ sale@ or use in connection with any method@ apparatus@ or product covered by letters patent@ nor as insuring anyone againstliabilitiesfor infringement of letters