Electrical Safety after SANDY  

By D. Jerry Flaherty, Chief Electrical Inspector, Electrical Inspection Service Inc.

(631) 286- 6642 - (516) 466-6486                               WWW.EISLongIsland.com 

A lesson learned from Katrina is that the storm water after the hurricane can be as dangerous as the hurricane itself.  Storm water can contain sewage, septic runoff, gasoline, oils, insecticides, fertilizer, salt in large quantities and a whole host of other pollutants and contaminants.  Storm water is a health hazard, fire hazard and very corrosive.  Energizing a building that is or was submerged in storm water can lead to electric shock, electrocution or burst into flames. Wiring and electrical equipment that has been dried can still be dangerous, the film left by the storm water can be conductive, corrosive and lead to black mold. Extreme caution should be exercised when working with electricity.  The information below is a synopsis from Underwriters Laboratories®, International Association of Electrical Inspectors® and National Electrical Manufactures Association®. 

NEVER ENTER A FLOODED BASEMENT OR CRAWL SPACE THAT MIGHT HAVE ENERGIZED ELECTRIC CIRCUITS IN OR NEAR THE FLOOD WATER.  THIS WATER COULD BE ELECTRIFIED AND WET BODY SKIN HAS VERY LITTLE RESISTANCE TO ELECTRICITY. ELECTROCUTION CAN RESULT!! 

Electrical Wiring Systems- NM cable (Romex) and AC cable (BX) should be replaced if submerged in storm water. These cables are listed for dry locations and not evaluated for wet locations or the contaminants that are in storm water. The paper wrap will absorb the storm water by wicking. Once in the cable, the storm water can be conductive causing a short circuit or a low resistance circuit that could lead to overheating and possibly a fire. The contaminants in the storm water could also be very corrosive and cause a low or high resistance connection. Old style Romex with braided jackets used in homes built in the 1980’s and earlier and BX cable should be replaced without question. 

Devices and appliances- Circuit breakers, switches, receptacles, appliances, furnaces, motors, should all be replaced if submerged in storm water. Storm water entering a circuit breaker or other device can cause electricity to ark across internal components or when dries cause the internal components not to operate properly. Circuits might not trip when required or might trip intermittently.

GFCI, AFCI and other electronics will not function after being contaminated by storm water.

Appliances and motors bearings will fail when contaminated by water. 

Portable Generators – Never use a generator or any gasoline engine indoors, the carbon dioxide (CO) produced is colorless and odorless and can kill.

Never connect a generator to building electrical system where any part of the electrical system, any appliance or the gas/oil burners is or has been submerged in storm water. Storm water is conductive,  when an electrical system, an appliance or burner is energized, the damp or wet wiring will energize the storm water. Anyone in the water or touching a wet or damp surface from the storm water could receive an electrical shock or be electrocuted. 

Health Issues – Do not drink, cook, bathe, brush teeth, or wash anything with storm water.

Disinfect all material, eating utensils, clothing and surfaces that come in contact with storm water.

Discard all carpeting, upholstery, furniture, bedding, etc. that has been in contact with storm water.

Remove and discard drywall and insulation that has been in contact with storm water.

Additional information: UL® http://www.ul.com/global/eng/pages/offerings/perspectives/regulator/

electrical/additional resources/flooding/

NEMA® http://www.nema.org/Standards/ComplimentaryDocuments/Evaluating-Water-damaged-Electrical-Equipment.pdf

If you have any comments, questions or suggestions please send to JerryFL@optonline.net