Firefighters wear Nomex or Kevlar suits. Both are fire-resistant fabrics that assist prevent the firefighter from becoming engulfed in flames or suffering burns while battling a nearby fire. Nomex and Kevlar are sometimes combined. For example, a combination jacket/pants set might be made out of Nomex with embedded kevlar fibers. There are two types of firefighting equipment used by firefighters: protective clothing and weapons. Protective clothing includes coats, pants, boots, and gloves. Weapons include axes, hoses, ladders, and tools. Firefighters must be careful not to injure themselves while wearing protective clothing. Axes can cause serious injuries if not used properly. Hoses can be very dangerous if not handled properly. Ladders can lead to injury if not used correctly. Tools can be very useful in treating patients or building structures. However, tools can also cause injury if not used carefully. For example, a tool called a "spike" can be used to stop blood flow to a vehicle's fuel tank to end its movement on the road if it is going to explode. Firefighters usually receive training on how to use their equipment before they go into action. Sometimes, new employees will be given a trial run with a non-live situation to make sure they don't have any problems operating certain devices.