Question

What was the status of U.S. workplace safety laws in 1900?

Answer 1

In 1900, there were NO "workplace safety laws"!

Explanation:

At the beginning of this century, workers in the United States faced remarkably high health and safety risks on the job.
https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4822a1.htm

A century ago in 1900 about three hundred out of every one hundred thousand miners were killed on the job each year.
[Industria] developments occurred within a legal and regulatory climate that diminished employer’s interest in safety. As a result, Americans developed production methods that were both highly productive and often very dangerous.
http://eh.net/encyclopedia/history-of-workplace-safety-in-the-united-states-1880-1970/