1. What Is Inside the Rubber Strip Around a Fridge Door?
The soft edge of a fridge door is called a gasket, or simply a door seal. In most fridges it is not plain rubber. Many seals contain a magnetic strip, and it is this strip that sticks to the metal cabinet to complete the seal. [2]
One manufacturer of rubber magnets explains how the strip is made. Powder from a magnetic material, usually ferrite, is mixed with synthetic rubber and shaped into a flexible band or sheet. Some versions use neodymium powder instead. [1] The maker lists fridge door seals as a long-standing use of the ferrite kind. [1]
The rubber matters as much as the magnet. A solid metal magnet is hard and brittle. A rubber magnet bends, can be cut with ordinary tools, and can have holes punched in it, so it can follow the four sides and corners of a door. [1] The same maker also notes that ferrite rubber magnets are fairly weak, so the job has to suit them. [1]
2. How a Magnetic Strip and a Steel Cabinet Hold a Fridge Door Shut
The magnet in the door has something to grab: the metal of the fridge cabinet. A gasket maker in the UK describes it this way. The seal must be airtight and must also hold firmly against the body of the fridge. Most fridge seals contain a magnetic strip, and that strip "sticks" to the metal unit to complete the seal. [2]
Why does the seal matter? If cold air leaks out, warm, damp air flows in. The food spoils sooner, mold can grow, and the fridge has to run harder, which raises the electricity bill. [2]
The rubber magnet is usually magnetized in stripes, with north and south poles alternating along the strip. The maker says a stripe width of about 5 millimeters is typical, and that this arrangement suits uses where you want one face to cling strongly. [1] That is a description of rubber magnets in general. I did not find a source that gives the stripe width for a particular fridge.
3. Why Old Latched Fridge Doors Could Trap Children
Before the mid-1950s, household refrigerators were typically closed with a latch that could be opened only from the outside. [4] That worked fine for keeping the door shut. But a child who climbed inside while playing and pulled the door closed had no way to get out. UL, the safety-testing organization, says these fridges carried a serious risk of suffocation for trapped children. [4]
This was a real problem, and people noticed. A medical researcher's review says that in the late 1950s, countermeasures were introduced to cut the number of deaths from fridge and freezer entrapment. [5] One of those countermeasures was a law.
4. What the 1956 Refrigerator Safety Act Required, and What It Did Not
In the United States, the Refrigerator Safety Act (Public Law 84-930) was signed on August 2, 1956. It made it illegal to ship a new household refrigerator across state lines unless it had a device that lets the door be opened from the inside. [3]
The text is short. It tells the Secretary of Commerce to publish standards for devices that let the door "be opened easily from the inside." It was to take effect one year and 90 days after those standards were first published, giving manufacturers time to redesign. [3] Today the job of enforcing it belongs to the Consumer Product Safety Commission, the US agency that oversees product safety. [3]
Notice what is missing. The law says nothing about magnets. UL explains that a fridge can meet the rule by letting you push the door open from inside, or by fitting a knob inside like a doorknob. [4] UL's refrigerator standard, UL 60335-2-24, specifically allows magnetic door gaskets to count as the latching device. [4]
So the statement "a law made fridges use magnets" is not accurate. A better statement is that magnets became one workable way to meet the law's safety rule. A gasket company claims the magnetic seal was invented in response to the 1956 act. [2] I could not confirm that from a government or engineering source, so treat it as a plausible story rather than a settled fact.
A simple way to picture why magnets suit this job is that one strip does two things at once. It pulls the door closed against the cabinet, and a hard enough push from inside peels it away. A latch has to be designed with a release. A magnet already has a built-in "give."
5. How Safety Testers Check That a Magnetic Door Opens From Inside
Under UL's standard, a closed fridge door goes through a door-latch release test. A set force is applied from the inside to imitate a child pushing or kicking the door. The force is applied at three places: near the top, near the bottom, and midway between. The door has to open for the fridge to pass. [4] UL's page gives the force as "15 lb-ft", but lb-ft is normally a unit of torque, not force, so I left the number out rather than guess what was meant.
The standard also requires a warning in the product literature. In plain words, it tells people who are throwing away an old fridge or freezer to take off the doors and leave the shelves in place so children cannot easily climb in. [4]
6. Did the Law and the Magnetic Seal Reduce Child Deaths?
The evidence points to yes. A 1985 review in the journal Public Health Reports says that for refrigerator and freezer entrapment, there appears to have been a significant decline in incidence after the measures of the late 1950s. I could read only its abstract, not the full text. [5] UL also says suffocation deaths declined significantly after the law went into effect. [4]
For numbers, a Japanese consumer newspaper reported figures in 2022 from a CPSC history page for the agency's 50th anniversary. According to that report, 96 children died from refrigerator entrapment between 1973 and 1984. The CPSC page then said that after the rules were strengthened, the most recent 25 years brought 2 deaths, and called such accidents "nearly zero." [6] I did not read the CPSC page itself, so I treat these figures as reported, not confirmed.
7. How to Check Your Own Fridge Door Seal With a Sheet of Paper
You can test whether a door seal still grips. Close the door on a sheet of paper so that the paper sticks out. Then slowly pull it. If it slides out with almost no resistance, the seal may be worn or dirty at that spot. A UK gasket maker describes this same test, using paper or a banknote. [2] Try it at several places around the door and compare the top, bottom, and sides.
Do it with a grown-up, keep it quick so the food stays cold, and don't leave the door open. Never climb inside a fridge or freezer, even as a game. If your family is getting rid of an old fridge, follow the warning above: take the doors off first.