By Al Henkel, NBC News producer

Before they step onto the fire line, every wild land firefighter in the country straps on a fire shelter, a small tent-like object, coated with aluminum reflective material which they hope they never have to use. If you can't get away from an approaching fire front, you ditch your pack and tools, climb into the shelter and wait it out. The shelter can shield whoever is inside from about 95% of radiant heat. It begins to delaminate, and melt at about 500 degrees. Shelter deployments are rare, but every firefighter is trained to get inside it in less than 20 seconds. Watch a demonstration.

This week, 12 orange County Fire Authority firefighters were forced to deploy their shelters at the Santiago Fire in Southern California. They were chasing a spot fire that was headed towards a small mountain community, dragging hose through waist high brush. The winds were whipping, and small fire grew very quickly. They were trapped on a ridge in sight of a highway, and in sight of a Los Angeles Times photographer who shot an amazing series of photographs. Photographer Karen Tapia-Anderson told us that she thought she was watching firefighters die right in front of her lens. "My heart was breaking for those men. Through my shroud and my goggles I can honestly say I began to cry myself because I felt like they weren't going to make it. And I began to pray for those guys. I did.  I prayed for those guys that they would be ok, I really did"

We met 5 of the 12 at their deployment site. In the typical firefighter manner, there were no tears, no wistful words, just a matter-of-fact explanation of what happened. Firefighter Brett Cowdell found the depression he scooped in the dirt to find clean air. "I deployed my shelter, put my face to the ground right here and jumped inside. We're already huffing and puffing cause we climbed the hills as fast as we could get up here I'm in the ground and I've got protection on my mouth, but it is burning as it's coming in." 

They were lying down on the ground that a fire had just passed over inside a foil pup tent, trapping all that heat inside. Estimates of the ground temperature: between 300 and 500 degrees. Imagine lying down inside your oven.

All 12 walked down the hill. All 12 were checked out by paramedics. All 12 wanted to go right back out on the line. You see, the fire was still moving towards people and houses. All of them wanted to do keep doing their jobs.

When I was a young reporter, I was interviewing a firefighter and he took his helmet off. Inside, next to a picture of his wife and kids, was written this verse: Isaiah 43:2. "When you pass through the waters, I will be with you; And through the rivers, they will not overflow you. When you walk through the fire, you will not be scorched, nor will the flame burn you." He told me you would be hard pressed to find a firefighter without that verse written somewhere in his gear.

That verse has been in my helmet ever since.

Don Teague and I will bring you the story of the Santiago Fire story tonight.