Current limits for exposures to nonionizing electromagnetic fields (EMF) are set, based on relatively short‐term exposures. Long‐term exposures to weak EMF are not addressed in the current guidelines. Nevertheless, a large and growing amount of evidence indicates that long‐term exposure to weak fields can affect biological systems and might have effects on human health. If they do, the public health issues could be important because of the very large fraction of the population worldwide that is exposed. We also discuss research that needs to be done to clarify questions about the effects of weak fields. In addition to the current short‐term exposure guidelines, we propose an approach to how weak field exposure guidelines for long‐term exposures might be set, in which the responsibility for limiting exposure is divided between the manufacturer, system operator, and individual being exposed. Bioelectromagnetics. © 2020 Bioelectromagnetics Society