You may have heard the electricians say, ‘Never take a shower when the washing machine is running.’ This sounds like a rare but plausible electrocution risk, or simply a statement to prevent you from being hot and then having a cold shower due to a sudden burst of cold water, but there is much more to it than that; that being said, there is much more danger than just the plumbing there; this is also a dangerous intersection of water and what is referred to as ‘leakage current’.In fact, if your washing machine has a combination of very small amounts of electrical leakage, you could have an electrical shock from the water in your shower due to the use of the washing machine, as there can be enough stray electricity flowing through the shared plumbing system that runs through your home; when using the washing machine, this could actually lead to your body completing the circuit to ground for that stray electricity to flow to the ground.
Realising this hidden danger could literally save your life.
Never take a shower while the washing machine is running
The hazard is not only due to a faulty plumbing installation, but it’s also caused by an electrical grounding fault. Washing machines are significantly heavy and have a large amount of vibration, and as a result, the internal wiring eventually breaks down. If the live electrical wire makes contact with the chassis or the wet-end of the pump of a washing machine, then the electric current does not stay in the washing machine; it travels through the discharged water, through the copper pipework of your home or common sewer systems.
Water has a high electrolytic conductivity; your shower will serve as the termination point for the leakage current caused by the grounding fault.
How washing machine shorts electrify showers
In most home layouts, the shower and washing machine share the same waste pipe. As such, if the washing machine motor shorts out, then the greywater exiting the washing machine is now electrically charged. Greywater contains minerals and detergents that create extremely high conductance.
If you are in the shower when the discharged greywater from the washing machine is electrified, this will create an energised standing water on the wet floor of your shower, which is a serious hazard to your health and safety.
Wait before you shower: The 40-minute buffer
Waiting a minimum of 30 to 40 minutes after the ‘End’ light turns off will not only allow time for any leftover water to drain from the machine, but also allow the entire system to shut down. Even when the drum has stopped turning, any moisture remaining near the motor (such as in the discharge hoses) will act as a path for electricity. Allowing time for the pipes to fully drain and for the machine’s components to cool will help break the physical connection between your laundry room and bathroom.
