An oil filled radiator is a common form of convection heater used in domestic heating. Electricity is channelled into a resistor inside the heater, which turns the energy into heat. That heat is absorbed by the diathermic oil that is enclosed in the heater. As the oil in the heater warms up, it begins to circulate through the fins and columns. As the oil moves, it transfers heat into the metal of the heater's fins, creating an even surface temperature. As the metal fins heat up, they begin to radiate heat into the room. This heat is circulated throughout the room by natural convection in the air. Oil filled room heaters neither burn oxygen nor reduce humidity making the best choice for heating rooms, especially for elderly people and babies. In this regard they are healthy options as it won't cause any suffocation or dry eyes, skin rashes. Oil filled room heaters safe as their surface won't heat up much. You don't need to place them closer to the bed. Simply put the Oil filled room heaters in the corner of room.