The effect of conventional factors on the free radon production rate above 0 degrees C has been widely studied, but rarely explored under frozen conditions. In order to investigate the effect on the free radon production rate of uranium tailings under frozen and non-frozen conditions, uranium tailings from southern China were selected for screening, and temperature, water-solid mass ratio and particle size were used as influencing factors for research. The stable radon concentration and the free radon production rate of uranium tailings of varying particle sizes at different temperatures (20 d...