NBC suit
An NBC (nuclear, biological, chemical) suit, also called a chemsuit or chem suit or chemical suit is a type of military personal protective equipment. NBC suits are designed to provide protection against direct contact with and contamination by radioactive, biological or chemical substances, and provides protection from contamination with radioactive materials and some types of radiation, depending on the design. It is generally designed to be worn for extended periods to allow the wearer to fight (or generally function) while under threat of or under actual nuclear, biological, or chemical attack. The civilian equivalent is the Hazmat suit. The term NBC has been replaced by CBRN (chemical, biological, radiological, nuclear), with the addition of a new threat, radiological, meaning radiological weapon.
Logo of NBC
In 1953, a stylized xylophone and mallet was introduced, accompanied by the NBC chimes, which were first heard on NBC radio in 1927 as a seven-tone sequence. The current tones – which were first adopted in 1929 as a simplified cue for identification of its radio affiliates because of issues with orchestrating the seven notes properly – are only three notes, G, E' and C' (contrary to popular belief, the selection of the three notes was not intended to represent the initials of the network's eventual owner, the General Electric Company, which was an early shareholder in RCA, which itself founded NBC by creating it as a subsidiary). There is some indication that the xylophone logo was used at 5:32 p.m. Eastern Time on December 17, 1953 to announce the Federal Communications Commission's (FCC) approval of the new color standard, which would go into effect 30 days later. This logo debuted in December 1953, during the Tournament of Roses Parade.