['To investigate the ability of electromagnetic (EM) field pre-exposures to induce protection in chick embryos against subsequent ultraviolet (UV) light exposure.', 'Chick embryos in the 4th day of gestation were exposed for 20 minutes (short term) or 96 hours (long term) to 60 Hz, 8 microT magnetic or sham fields (controls) followed by 30 minutes rest. They were then exposed to UV radiation of either low (30J/m2) or high (45J/m2) intensity (long term was exposed only to 30J/m2) for 75 minutes. Mortality measurements were made every 30 minutes following UV exposure.', 'At both UV intensities, short-term, EM field-exposed embryos showed significantly higher post-UV survival (p<0.05) at each time point as compared to controls. Long-term EM field exposures, however, offered no protection against low intensity UV light, in fact, 96 hour-EM field-exposed embryos were significantly less protected than non-EM field-exposed controls (p<0.05).'] Do short-term magnetic field exposures ( 60 Hz ) induce protection against ultraviolet radiation damage?