A shock from a faucet is not normal and not a leak. Stop touching it and call a licensed electrician. On the plumbing side, metal pipes that are not bonded, a repair that breaks metal continuity, or a water heater isolated from ground can leave metal fixtures energized. A tingle can start as a warning.
Why is a mild shock still a warning?
Because it is the same event as the stronger shocks, only smaller. OSHA's table of effects shows how quickly the sensation changes with current: at 1 milliampere it is a "faint tingle," at 5 milliamperes a "slight shock felt; not painful but disturbing," and at 6 to 25 milliamperes for women and 9 to 30 for men "painful shock, loss of muscular control." A tingle is the bottom of that scale, but you cannot tell the current from the feel alone.
Water matters here. OSHA says that when skin is "moist or wet, it acts as a conductor," and that the severity of a shock depends on "the amount of current flowing through the body, the current's path through the body, the length of time the body remains in the circuit, and the current's frequency." A faucet is the place where wet hands and metal meet.
What plumbing-side problems can make a faucet energized?
An electrician decides which one it is. These are the causes that live in the plumbing system, and what to tell the electrician.
Metal water pipes that are not bonded. An article in IAEI Magazine, from the International Association of Electrical Inspectors and written for the 2005 National Electrical Code, explains that section 250.104(A) requires metal water piping installed in or attached to a building to be bonded, and says that "if metal water piping systems are not bonded to the electrical system in a way that meets the requirements of the Code, they can present a fire or shock hazard within the building or structure because they could become energized." Bonding means joining the metal parts so they stay at the same voltage. If a fault elsewhere puts voltage on the pipes and nothing ties them to the electrical system, that voltage waits for someone to touch a faucet.
A repair or repipe that broke the metal path. The same IAEI article notes that when metal water piping "is replaced with nonmetallic piping," the electrical continuity is interrupted. It adds that short sections of metal inside a plastic system typically are not required to be bonded, because they are not a full metal piping system. So the question is not whether some pipe is plastic. It is whether the metal that remains is still tied to the electrical system the way it should be. After a partial repipe, a sink repair or a water heater swap, tell the electrician what was changed and when. Our page on PEX versus CPVC pipe covers the plastics homeowners most often have installed.
A water heater cut off from ground. Rheem's manual for electric water heaters warns: "The presence of water in the piping and water heater does not provide sufficient conduction for a ground. Non-metallic piping, dielectric unions, flexible connectors etc. can cause the water heater to be electrically isolated." In other words, the way the water heater is plumbed can remove a path that its grounding relies on. The same manual says the branch circuit wiring must be provided by a qualified electrician. If the shock is on the hot side only, mention the water heater.
An appliance that is connected to the plumbing. Dishwashers, disposals and water heaters tie electricity to the water supply or drain. A fault inside one can put voltage on metal parts. OSHA explains that an equipment grounding conductor is "a low-resistance wire that directs unwanted current directly to the ground," so a broken ground at the appliance, outlet or panel is an electrician's repair.
None of this is a do-it-yourself test. Meters and jumper wires on a live system are for licensed electricians.
Could it be static instead?
Sometimes. A single snap right after you walk across carpet, with nothing before or after, is a static spark, and Phoenix air is dry. A tingle or buzz that continues while you hold the faucet or run the water is not static. If you cannot tell, treat it as an electrical fault.
What should you do right now?
- 1Stop using that faucet and fixture. Do not touch metal fixtures with wet hands.
- 2Keep children and pets away from it.
- 3Call a licensed electrician today. Tell them where you feel it, whether it is hot, cold or both, and what plumbing or appliance work was done recently.
- 4Do not use a breaker as a fix. If you know which circuit serves a suspect appliance, an electrician can confirm it; a tripped breaker is not a repair.
OSHA notes that ground-fault circuit interrupters (GFCIs) are used in wet locations and "interrupt the flow of electricity within as little as 1/40 of a second," shutting off power if the current difference exceeds 5 milliamperes. A GFCI is protection, not a fix for the cause of a shock at your faucet.
What does Phoenix require for the electrical side?
Phoenix's building code says that "the provisions of the National Electrical Code, as amended, shall apply to the installation of electrical systems," including repairs and alterations. The bonding rules for metal piping are in the NEC's Article 250, section 250.104. This page does not reproduce the current section text, so ask your electrician to apply it to your house.
Where does a plumber come in?
HQ Plumbing and Air handles the plumbing, not the wiring. After an electrician finds the fault, we can inspect and repair the plumbing side: pipe materials and connections, dielectric unions and flexible connectors on a water heater, and replacing worn fixtures. We are licensed and insured, and we give free estimates and upfront pricing. See our residential plumbing service or our page on what to do when an electric water heater keeps tripping the breaker.