OSHA has updated its free heat illness app with some new features for iPhone users.

The app, which was launched in 2011, allows workers and supervisors to calculate the heat index for their worksite, and, based on the heat index, displays a risk level to outdoor workers. Then, with a simple "click," you can get reminders about the protective measures that should be taken at that risk level to protect workers from heat-related illness- reminders about drinking enough fluids, scheduling rest breaks, planning for and knowing what to do in an emergency, adjusting work operations, gradually building up the workload for new workers, training on heat illness signs and symptoms, and monitoring each other for signs and symptoms of heat-related illness.

Heat illness sickens thousands of workers every year, and severe cases can be fatal.

With an attractive, easy-to-use interface, the new version is optimized for the latest iPhones. The app automatically provides the current conditions and maximum heat at your location and can accept manual input if users don't have cell service.

Click here to get the app.