How TAMPER RESISTANT RECEPTACLES Work & Where They’re Required By The National Electrical Code
Found in Article 406.12 of the 2020 NEC, these protective receptacles have been found in the NEC since the early 80’s, requiring “Tamper Proof” receptacles in all pediatric care facilities by 1981 and later psychiatric wards in 1984. The terminology switched to “Tamper Resistant” in 1990, the NEC dropping it’s requirements for psychiatric wards in 1993.
NEC Code Article for TRRs
TRRs are required for all 15- & 20-amp receptacles below 5ft 6 in (66”) in all areas children might find themselves wandering about, including residential buildings, childcare facilities, hotels, waiting rooms/ hallways of medical facilities, and most “assembly occupancies” (auditoriums, gyms, transportation waiting lobbies, skating rinks etc.) exception: appliance circuits that are not easily accessible (mirco, fridge and others)
Internal shutters on loaded springs block foreign objects from being inserted until equal force is applied into both the hot and neutral terminals. If excessive force is needed, it usually means uneven pressure is being applied by the blades of the plug or there is a problem with the receptacle itself.
TRRs so far seem to be the most complete solution to childhood shock/electrocution caused by receptacles. The most common objects inserted into receptacles being hair pins, keys and paper clips.
Dummy with a Toothpick
Outlet caps (the most common and affordable option) seem to provide very little protection. Studies prove that most children over two could remove caps, and the risk of babies putting the caps in their mouths outweighed the benefit of shock protection. In fact, plastic plug inserts are not approved by any of the major listing companies for child protection uses, only listed as insulating devices aimed at energy conservation. Price differs between TR and standard by only around 50 cents per plug, and as a standard middle-class home usually has less than 100 plugs, that’s only a $50 difference in material!
Stay safe out there folks! Love from the ATX