For a flash fire, the danger zone is:

For a flash fire, the danger zone is:

• A. Within the flammable cloud
• B. In the control room
• C. Upwind of the fire
• D. In the nearest shelter

Answer: (A)

In a flash fire, the danger lies in the flammable vapor cloud itself. When a flammable release mixes with air and an ignition source is present, the flame can flash through the entire cloud in an instant. Because any part of that cloud can ignite and the cloud can spread with the wind, the immediate risk area is the cloud, not a specific fixed location like a room or a shelter. So you’re most exposed if you’re within the flammable cloud, whereas spaces that are free of vapors—and away from any ignition sources—are the safer targets for evacuation or protection.

In a flash fire, the danger lies in the flammable vapor cloud itself. When a flammable release mixes with air and an ignition source is present, the flame can flash through the entire cloud in an instant. Because any part of that cloud can ignite and the cloud can spread with the wind, the immediate risk area is the cloud, not a specific fixed location like a room or a shelter. So you’re most exposed if you’re within the flammable cloud, whereas spaces that are free of vapors—and away from any ignition sources—are the safer targets for evacuation or protection.