A deceleration switch comprising a support member, a permanent magnet mounted on the support member and displaceable from a first position to a second position by inertia caused by a predetermined deceleration of the support member, a spring mounted on the support member for biasing the permanent magnet toward the first position, a set of electrical contacts mounted on the support member and operable to close under the influence of the magnetic field of the permanent magnet when the permanent magnet is in the second position and an inductive device energized to produce a second magnetic field enhancing the magnetic field of the permanent magnet thus causing the contacts to remain closed for a longer period of time upon return of the permanent magnet to its first position under the biasing action of the spring.