Chemical Corps affiliation with the corps. The Chemical Corps branch insignia consists of a cobalt blue, enamel benzene ring superimposed over two crossed gold retorts. The branch insignia, which was adopted in 1918 by the fledgling Chemical Service, measures .5 inches in height by 1.81 inches in width. Crossed shells with a dragon head was also commonly used in France for the Chemical service. The Chemical Warfare Service approved the insignia in 1921 and in 1924 the ring adopted the cobalt blue enamel. When the Chemical Warfare Service changed designations to the Chemical Corps in 1946 the symbol was retained. The regimental
Au pair Au pair An au pair (; plural: au pairs) is a domestic assistant from a foreign country working for, and living as part of, a host family. Typically, au pairs take on a share of the family's responsibility for childcare as well as some housework, and receive a monetary allowance for personal use. Au pair arrangements are subject to government restrictions which specify an age range usually from mid-late teens to mid to late twenties; some countries explicitly limit the arrangement to females. Arrangements differ between Europe, where the concept originated, and North America. In Europe, au pairs are only