What is the difference between dart rate and severity rate?

DART rate is a calculation of your company's Days Away/Restricted duty/Transfer CASES.

Severity rate is a calculation of how severe your accidents are as it takes into account number of DAYS away from work for each case.

So in summary, you can have a low DART rate by having very few injuries where employees are missing work, having restrictions or transferring to other departments. You can have a low severity rate by having a DART cases where the employee only misses a few days from work per case.