Term for people who are somewhere between blue collar workers and white collar workers [closed]

Solution 1:

Interesting question. I couldn't think of anything off the top of my head so I did a quick search and found this article. The new types of 'collars' certainly seems to be a response to the changing labor landscape and increase in the need for and prevalence of technical skills.

To your point, railroad engineers or technicians would be likely be 'grey collar'. I would classify the FD/PD as blue collar though.