In-flight radiation for pregnant women

The earth's atmosphere blocks most cosmic rays, but at higher altitudes the exposure to radiation increases. Nonetheless, pregnant women who occasionally travel by air can be assured that the harm to their fetus from cosmic radiation is negligible, according to recent research. However, on the rare occasion of solar flare it is possible to be exposed to a potentially harmful dose of radiation.The Space Environment Centre (SEC) of the National Oceanic and Atmospheric Administration, USA maintains a web site (www.sec.noaa.gov) with real-time data on when a solar flare is occurring. Pregnant women can check this web site and, if necessary, postpone their flight by a few hours until the high-dose period has passed. Also, the US Federal Aviation Administration (FAA) and the SEC has recently introduced an alert system that sends a warning to at-risk airlines to lower their altitude to a level with less radiation exposure. This is meant to protect those pregnant women who are already in the air when a solar flare occurs.At present, it is recommended that radiation exposure should not exceed 1 millisievert (mSv) over a 40-week pregnancy. Most research has suggested there is no evidence of fetal harm with exposure levels below 20 mSv. The radiation risk for pregnant women who fly on a more regular basis, such as crewmembers and frequent business travellers, requires a more detailed analysis, according to researchers from the Lenox Hill Heart and Vascular Institute in USA.

For these women, the FAA has created software, accessible on the Internet, which can calculate the in-flight radiation dose on a trip-by-trip basis. Coupled with the recommended dose limits, the software should help women decide how much flying they are comfortable with.