Abstract: An omnidirectional inertia switch comprises a conductive spherical seismic mass supported concentric with respect to a stationary spherical conductor by a spherical elastomeric suspension member which deforms under inertial loads and permits electrical contact between the seismic mass and the stationary conductor to provide a signal. In one embodiment, the stationary spherical conductor is positioned centrally in a spherical cavity. The spherical seismic mass is hollow and surrounds the stationary spherical conductor. The elastomeric suspension member is positioned between the surface of the spherical cavity and the outside surface of the spherical seismic mass. In another embodiment, the spherical seismic mass is positioned within a spherical cavity defined in a housing, and the elastomeric suspension member is positioned therebetween and includes a plurality of openings permitting contact therebetween.