[en] When high energy electrons are accumulated in a storage ring for the production of synchrotron radiation, the main source of concern for radiation protection, apart from accidental loss of the e^- beam, is the production of high energy gamma rays from bremsstrahlung interaction of electrons with residual gas in the vacuum chamber along the straight sections of the ring. Synchrotron radiation (SR) beams from insertion devices are extracted at the end of the straight sections so that the gas bremsstrahlung is channelled through the beamlines. However, even at third generation synchrotron radiation facilities, bending magnets are used as SR sources: the related extraction line is generally at a certain angle from the straight section. Gas bremsstrahlung is also produced along the curved trajectory of the electrons in the bending magnets and is channelled along the SR beam line. Safety measures similar to those for the straight lines are to be considered for the bending lines. We propose an expression for evaluating the dose from gas bremsstrahlung produced in a bending magnet. (author)