The United States has revised the medical requirements that allow a commercial airline pilot to fly safely. This was decided by the Federal Aviation Administration (FAA), which recently expanded the acceptable range for heart rhythms based on "new scientific evidence" that emerged during the pandemic.

In particular, the agency has increased the maximum "PR" interval for first-degree atrioventricular block to 300 milliseconds for pilots of all ages (previously it was 210 only for those under 51), while for intervals longer than 300 milliseconds, the FAA will decide on the suitability of the pilot on a case-by-case basis.

The agency said it followed "standard processes based on data and science" to determine that it could "safely increase the tolerance used to screen for a given heart condition" and notified certified aero-medical examiners of the change.