Since ether is heavier than air it can collect low to the ground and the vapour may travel considerable distances to ignition sources, which does not need to be an open flame, but may be a hot plate, steam pipe, heater etc. Vapour may be ignited by the static electricity which can build up when ether is being poured from one vessel into another. The autoignition temperature of diethyl ether is . A common practice in chemical labs is to use steam (thus limiting the temperature to ) when ether must be heated or distilled. The diffusion of diethyl ether in air is (298 K, 101.325 kPa).