Mutual aid
The Great Baltimore Fire in 1904 burned for 30 hours straight and decimated a major part of central Baltimore, including over 1,500 buildings. Mutual aid companies from as far away as Washington D.C., Philadelphia and New York City were called in to assist. The fire led to uniform national standards in fire fighting equipment and protocols. As with other large fires of the time, it was a predecessor to the stringent fire codes of today.