Electronics module assemblies (“EMAs”) for inflatable personal restraints and associated systems are described herein. An EMA configured in accordance with an embodiment of the present technology can include, for example, a housing having a body portion, cover portion that attaches to the body portion to form an enclosure, and protrusion extending outwardly from the cover portion. The protrusion can have an outer boundary at which the protrusion projects away from the cover portion. The EMA can further include a crash sensor within the enclosure in an area defined by the outer boundary of the protrusion. The protrusion can form an envelope of space around the crash sensor that defines a minimum distance an external object with a magnetic field can come to the crash sensor without activating it. The EMA can optionally include a magnetic field configured to disable the crash sensor upon the detection of an external magnetic field.