Some people think the Federal Communications Commission updates its cell phone radiation rules every few years. It does not. The basic limit that decides how much radio energy a phone can put into your head has not changed since August 1996. That is the year the FCC adopted the 1.6 watts per kilogram number, averaged over any one gram of tissue. It is called the specific absorption rate, or SAR. Every phone sold in the United States is tested against that same 1996 limit before it can be sold.

In 2019 the FCC did a formal review of its radio-frequency exposure rules. It looked at the science, read comments from the public and from industry, and then decided to keep the existing limits. Nothing got stricter. Nothing got looser. The 1.6 watts per kilogram number stayed. The testing method stayed. The agency said the current limits were good enough to protect the public.

The review did not end the debate. Some groups wanted lower limits, especially for children. They pointed to studies that suggested possible health effects from long-term phone use. They argued that the 1996 limits were designed for a time when phones were used less and carried differently. The FCC did not agree. It said the existing limits already had a large safety margin built in, and that the scientific evidence did not show a need for change.

Those groups then sued the FCC. In 2021 the D.C. Circuit Court of Appeals gave a mixed ruling. It upheld the FCC on the question of whether radio-frequency energy from phones causes cancer. The court said the agency had reasonably concluded the evidence did not support that link. But on other questions, such as whether the agency had properly considered effects on children, the court said the FCC had not explained its reasoning well enough. The court sent those issues back to the FCC for a better explanation. It did not order new limits. So the 1996 numbers are still the ones the FCC enforces today.

Every phone model sold in the US must pass a SAR test. The manufacturer runs the phone at its highest power level while it is pressed against a model of a human head or body. The test measures how much energy the tissue absorbs. The result must be at or below 1.6 watts per kilogram. That number is based on an older standard that most of the rest of the world does not use. Many countries follow the guidelines of an international commission called ICNIRP, which allows 2 watts per kilogram but averages it over ten grams of tissue instead of one. That difference in averaging changes the numbers more than the headline figures suggest. A larger averaging mass smooths out hot spots, so the two standards are not directly comparable.

If you want to know the SAR value for your phone, you can find it in the phone’s settings or in the paperwork that came with it. The full test results are on file with the FCC under the device’s FCC ID number. That tells you the phone met the 1996 limit when it was tested. It does not settle the larger health argument. That argument continues among researchers, regulators, and the public.

There is a fuller write-up at the-1996-limit.pages.dev.