On 11 June, 2008: SHELL TIMUR Sdn Bhd celebrated their Global Safety Day with a theme : Small Change, Big Difference. I was invited to give a talk on Ergonomics and Productivity.
On that day, all SHELL staff submitted their own pledge on safety based on the the above theme. One of the worker created his pledge : I will not drive if I drink.
Based on the theme, this pledge is Small Changes which the worker able to carry out and it has big impact on safety of the worker - Big Difference.
So you can adopt the idea and ask your employee to create their own pledge.