Welders inhale gases and respirable particles. To investigate the relationship between fluoride exposure and respiratory symptoms in welders using basic electrodes containing calcium fluoride, 63 railroad track welders were interviewed. Fluoride was measured in post-shift urine samples. Seventeen welders reported respiratory symptoms related to welding fume exposures. Respiratory symptoms were somewhat more common with increasing concentrations of fluoride in urine. The association between welding fume exposure and respiratory symptoms seems related more to fluorides than to other particles among welders using basic electrodes.