OSHA (Occupational Safety and Health Administration) publications are public domain and are great resources. You can go here for more:
https://www.osha.gov/publications/all
Most OSHA State Plans adopt federal standards and are the same, however, some states have stricter standards. Please check yours at:
https://www.osha.gov/stateplans
You can also learn about OSHA’s free on-site consultation and cooperative programs by going to:
https://www.osha.gov