What is a Tamper Resistant Outlet? How Does It Work?

Tamper-resistant outlets, also known as TR outlets, are electrical outlets that are designed to prevent accidental or intentional contact with the electrical contacts inside. These outlets are becoming increasingly popular in both residential and commercial settings due to their added safety features. This article will explore what a tamper-resistant outlet is, how it works and the benefits of using them.
What is a Tamper-Resistant Outlet?
A Tamper-Resistant Outlet, also known as a TR outlet, is an electrical receptacle designed to prevent accidental electrical shock or injury caused by the insertion of foreign objects into the outlet slots.
It looks like a standard wall outlet, but it features an internal shutter mechanism that prevents children from sticking objects like hairpins, keys and paperclips into the receptacle.
According to the NFPA®, approximately 2,400 children suffer severe shock and burns from sticking objects into unprotected receptacles. 2017 section 406.12 requires all non-locking 15- and 20-ampere, 125- and 250-volt receptacles in the areas specified in 406.12(1) through (7) shall be listed as tamper-resistant receptacles.
(1) Dwelling units in all areas specified in 210.52 and 550.13
(2) Guest rooms and guest suites of hotels and motels
(3) Childcare facilities
(4) Preschools and elementary education facilities
(5) Business offices, corridors, waiting rooms, and the like in clinics, medical and dental offices, and outpatient facilities
(6) Subset of assembly occupancies described in 518.2 to include places of waiting for transportation, gymnasiums, skating rinks, and auditoriums
(7) Dormitories
How do Accidents Happen?
Electrical injuries occur because of several factors:
- Pre-exposure conditions unintentionally exist
- A metallic object inserted into an outlet becomes electrified
- A child touching the object could receive a powerful electric shock
- Children have less resistance to electric shock than adults
The inserted object also contacts a grounding point and creates a short circuit, which results in arcing and heat that can cause burns.
Most objects are everyday household items that children can access easily. Alarmingly, nearly half of the items (hairpins and keys) are objects parents don’t often consider dangerous. The chart below reflects the wide variety of metal objects that children have been documented inserting into receptacles. They include but aren’t limited to paper clips, pens, safety pins, screws and nails, tools, wire, forks, tweezers, hairpins, keys, knives, and coins.

How Does a Tamper-Resistant Outlet Work?
This spring-loaded shutter system in a tamper-resistant outlet only opens when equal pressure is applied simultaneously to both shutters, such as when an electrical plug is inserted. Unlike plastic outlet covers, the tamper-resistant outlet provides automatic and continuous protection for children.

How Much Does it Cost to Install Tamper-Resistant Outlets at Home?
Required for years in healthcare facilities’ pediatric-care areas, tamper-resistant receptacles are easily affordable for homeowners. NEMA estimates an average retail price increase of $0.50 per tamper-resistant receptacle. The average new home includes 75 receptacles; therefore, homeowners could expect to pay an estimated $37.50 to make all outlets tamper-resistant. This translates to a cost increase of less than 0.5 percent on an average total electrical installation of $6,820.
One might argue that homeowners should have the choice of whether to install tamper-resistant receptacles, perhaps because no small children would live in the house, but circumstances evolve. Neighbors and grandchildren visit and homes change ownership. At less than $50 to protect an entire house, installing tamper-resistant outlets presents an arguably small homeowner investment to ensure the greatest level of electrical safety for children. If you want to buy a tamper-resistant outlet you can check the price from here.
Why Tamper-Resistant Outlets are Safer than Plastic Outlet Caps?
Since accidents can happen in seconds, preventive measures must be taken to ensure safety. There are several types of electrical safety products on the market, but even protective devices have shortcomings.
One popular device, the plastic outlet cap, offers an inexpensive “child-proofing” method. New parents often use plastic caps, and they are usually effective in protecting children under two years of age. However, statistics indicate that outlet caps could be ineffective in deterring toddlers and preschool-age children.
According to a 1997 Temple University Biokinetics Laboratory study of two plastic cap brands, 47 percent of four-year-olds tested could remove one brand of the cap. More alarming, 100 percent of the 2- and 4-year-old children removed the second brand of cap —and, in many cases in less than 10 seconds. It is important to remember that no device can protect if unused. Adults often forget to reinsert receptacle caps after using an electrical outlet, leaving the receptacle exposed. Children can also gain access to exposed receptacles by simply pulling out cords for lamps, alarm clocks, and other everyday devices. Child-resistant wall plates offer better levels of protection than outlet caps, but they also have dangerous flaws. Most add extra layers of material between the plug blades and the receptacle contacts. This reduces the surface area between plug blades and contacts, causing potential heat rise or arcing. Although not widely used in homes, tamper-resistant receptacles offer the most reliable solution.