Feb. 10, 2009— -- Pagers have been as synonymous with the medical community as scrubs, stethoscopes and lab coats.
But cell phones -- their electronic cousins -- have historically been persona non grata with the hospital set.
Electromagnetic interference from cell phones and other transmitting communication devices was thought to affect the performance of medical equipment.
Now, as technology improves, more hospitals in the United States and the United Kingdom are relaxing and lifting long-standing bans on cell phones.
But though the door is unlocked, it's not swinging all the way open. Experts caution that though the interference risks are low, they are still significant enough to warrant some limitations on cell phone use in health-care facilities.
In 2007, researchers at the Rochester, Minn.-based Mayo Clinic published one of the first reports to dispel the widespread notion that cell phones negatively affect patient care equipment.
Previous tests in 1997 and 2000 found that cell phones, especially older analog phones, could interfere with heart monitoring equipment and other sensitive medical instruments. In one case, a cell phone signal caused a ventilator to shut off.
But the most recent tests, on medical equipment better shielded against interference from wireless communication devices, showed researchers that the threat had dimmed.
In five months, the researchers performed 300 tests in patient rooms and determined that the normal use of cell phones resulted in no noticeable interference with medical equipment.
"When we watched the monitors, we didn't see anything that seemed clinically significant," Jeff Tri, one of the authors of the cell phone study, told ABCNews.com.
Those results -- combined with patient requests for cell phone use and the difficulty in enforcing a total ban -- not only persuaded the hospital to change its policy, but prompted it to encourage other hospitals to do the same.
"We said we don't think the incidence of interference is great enough to warrant the policy staying where it is," Tri said, adding that the two exceptions to the policy were the surgery and pediatric and neonatal units, as studying those areas would have required a different process.