The department of health shall take cognizance of the interests of life and health among the peoples of the state; shall make investigations into the causes of disease, the prevalence of epidemics and endemics among the people, the sources of mortality, the effect of localities, employments and all other conditions and circumstances on the public health, and do all in its power to ascertain the causes and the best means for the prevention and control of diseases or conditions detrimental to the public health, and adopt proper and expedient measures to prevent and control diseases and conditions detrimental to the public health in the state. It shall publish and circulate, from time to time, information that the director may deem to be important and useful for diffusion among the people of the state, and shall investigate and give advice in relation to those subjects relating to public health that may be referred to it by the general assembly or by the governor when the general assembly is not in session, or when requested by any city or town. The department shall adopt and promulgate rules and regulations that it deems necessary, not inconsistent with law, to carry out the purposes of this section; provided, however, that the department shall not require all nonprofit volunteer ambulance, rescue service, and volunteer fire departments to have two (2) or more certified emergency medical technicians manning ambulances or rescue vehicles.