This metric is based on the GRI G4 indicator G4-LA6. The GRI's Sustainability Disclosure Database is a good place to find companies that report according to the GRI standard. If you search for the company you want to research on this site, you should find a page like this that links to a HTM/PDF version of the company's report, and a link to an index that should tell you where data for each indicator can be found.
Within the source document (usually a CSR report) there should be a clear statement or table entry reporting the reduction in energy consumption. You can often look up the indicator G4-LA6 in the Global Reporting index of the CSR report to see which page you need to look at.
The G4-LA6 indicator calls on companies to:
Report types of injury, injury rate (IR), occupational diseases rate (ODR), lost day rate (LDR), absentee rate (AR) and work-related fatalities, for the total workforce (that is, total employees plus supervised workers), by:
Report types of injury, injury rate (IR), occupational diseases rate (ODR), lost day rate (LDR), absentee rate (AR) and work-related fatalities for independent contractors working on-site to whom the organization is liable for the general safety of the working environment, by:
Report the system of rules applied in recording and reporting accident statistics.
This metric is asking for the company's Total Recordable Incident Rate (TRIR) - a standardised measure of workplace injuries used by many companies.
See this page for more information about how TRIR is calculated.