A method for actuating a device, the method including: biasing a first movable member in a first direction; biasing a second movable member in a second direction; blocking a movement of the second movable member at a position along a second path when the first and second movable members experience a first acceleration having a first magnitude and a first duration; and allowing the second movable member to move along the second path past the position when the first and second movable members experience a second acceleration having a second magnitude and a second duration, the second magnitude being less than the first magnitude and the second duration being greater than the first duration.