Blue Collar and White Collar workers

[pussycat]

Where did the terms "Blue Collar" and White Collar" workers originate?

[ruby27]

http://en.wikipedia.org/wiki/White_collar

Not everyone trusts wikipedia sources but this looks a fairly unremarkable and a plausible explanation.

I thought white indicated shirt and collar so office based and blue was due to the overall worn, hence manual.

[abstibus]

I thought it had something to do with how often they needed to be washed.

[Ethel]

Until recent years, police inspectors and above wore white shirts, and sergeants and constables wore blue.

I don't think that is the origin, but is a clear representation of the situation