Showering during a thunderstorm is a legitimate safety concern, not an old wives’ tale. Lightning is a powerful electrical discharge that seeks the most direct path to the ground. A home’s infrastructure can inadvertently provide a convenient route for this current. Although the risk of being struck in the shower is statistically low, the potential consequences of electrocution are severe. Avoiding contact with water and plumbing fixtures during a storm is a necessary precaution.
How Lightning Enters the Home Systems
Lightning is an electrical current that travels through a home’s utility lines and metallic components as it attempts to reach the earth. The charge does not need to strike the house directly; a strike to the ground or a nearby utility pole can send a powerful surge into the residential system. This surge follows the path of least resistance, using external power lines, phone cables, and cable television wires as primary conductors for entry.
Once inside, the current moves through internal wiring and structural metal. Residential plumbing, particularly metal pipes made of copper or galvanized steel, offers another highly conductive pathway. These pipes run from underground sources up into the walls and fixtures, providing a direct, low-resistance route for the current. This network effectively channels the surge into the interior spaces of the building.
Why Plumbing Creates an Electrical Hazard
Plumbing systems create a localized hazard because they combine highly conductive metal fixtures with water, which also conducts electricity. While pure water is an insulator, the tap water used in homes contains dissolved minerals and impurities that significantly increase its ability to carry an electrical current. A person standing in the shower is exposed to both the conductive metal fixtures and the running, mineral-rich water.
If a lightning surge travels through the metallic piping, it instantly energizes every connected fixture and the water flowing through it. Touching a metal fixture while wet creates a complete circuit, allowing the current to pass directly through the body to the ground. Even homes with plastic (PVC) plumbing still have metal shower drains, faucets, and fixtures connected to the overall conductive system, maintaining the risk of shock. The combination of wet skin, grounded metal, and conductive water makes the shower an efficient conduit for electrical energy.
Practical Steps for Storm Safety Indoors
To minimize injury risk during a thunderstorm, avoid contact with all water and anything connected to electrical or plumbing systems. Postpone activities like showering, bathing, washing dishes, and doing laundry until the storm has passed. Stay away from corded phones, computers, and electronics plugged into wall outlets, as lightning surges can travel through the electrical wiring.
The safest practice is to wait for a period after the storm appears to be over before resuming normal activities. Experts recommend following the 30-30 rule: go indoors immediately when thunder is heard, and wait at least 30 minutes after the last sound of thunder. This waiting period is necessary because lightning can strike several miles away from the main storm, even after the rain has stopped. Staying away from windows, doors, and concrete floors or walls, which may contain reinforcing metal bars, also helps ensure safety indoors.