Sharp vision depends on many factors. The parts of the eye work together to bend (refract) and focus light rays.

Maintenance-free respirators are one of the most common types. They are worn to capture particles.

You are the only person responsible for your thoughts and actions. This simple idea is your most powerful tool for managing stress.

Learning to manage stress doesn't happen overnight. It's a process. The more you keep at it, the more you'll feel in control of daily events.

Focusing the mind helps provide stress relief. Taking 5 to 10 minutes to practice relaxation each day helps you feel more refreshed.

If you don't use a respirator, respiratory hazards can damage your respiratory system.

Even severe heat stress can appear suddenly, so learn the warning signs and how to treat them.

In hot environments, your body may have trouble keeping its temperature at a safe level. As a result, your body temperature rises to unsafe levels. This is heat stress. Heat stress can develop quickly. It can also be very dangerous to your health.

How much do you know about protecting your hearing? Take the quiz to find out.

Learn about how earplugs and earmuffs can protect you from hearing damage.