Abstract: A safety lockout adapter is formed of two coupling members. Each coupling member is adapted to couple with another corresponding coupling member of substantially similar configuration for locking-out power disconnects or fluid line disconnects. When connecting the members to the power disconnect handle, a worker must use both hands. Each coupling member comprises a substantially rigid and planar member having opposing front and rear edges and opposing side edges defining front and rear portions. The front portion includes on one of the side edges an arcuate portion extending inwardly to form a substantially concave cut-out and a hook portion defined by the front edge and projecting toward the side from the front of the concave cut-out. Means positioned along the side edge opposite the arcuate cut-out holds together two coupling members when reversed and coupled in overlapping registry with each other.