What employees themselves said:

• I don't want to get hurt.
• I don't want to let my family down by getting hurt and not being able to work.
• I worry about what my family would do if I got killed.
• I don't want my fellow employees to get hurt.
• I don't want fellow employees to get stuck with extra work if I get hurt.
• I don't want to be the one to ruin the company's safety record.
• I don't want to mess up my own good work record.
• I'll get in trouble with the boss if I get hurt.

What employers said they've found that works:

• Setting the example -- wearing PPE, following the rules.
• Enforcing the safety rules: having a written disciplinary policy and using it.
• "Let them know I'm watching what they do."
• Describe the bad things that can happen when something goes wrong.
• Listing the cost for workers compensation premiums on the pay stubs. (PDF)
• Explain the Golden Rule: "It's my gold, and I get to make the rules."