By using a wire free telemetry solution. Violent mechanical and electrical activity in humid air, such as in a thundercloud, and a large electric charge is delivered to the ground and this energy is then transferred to electronic equipment through cables.
The cables could be phone lines all power lines. Wireless monitors do not have phone line connections or power connections and are therefore not connected to the electrical energy.
A lightning strike near to equipment will often cause the equipment to fail, especially if there is a connection to earth. Whilst it is possible to protect equipment by the use of lightning arrestors this incurs costs and are not always sufficient to eliminate problems.