A Class 1, or Class A, fire rating means that the building material is highly resistant to fire and does not spread flames quickly. In the flame-spread rating test, a score of 0 to 25 constitutes a Class 1 rating. The score is relative and balanced between asbestos cement sheet, with a score of 0, and pure red oak, with a score of 100.Continue Reading
Building materials with a Class 1 fire rating are often man-made or nonorganic substances. The most extreme example is asbestos cement sheet, which is extremely resistant to fire but hazardous to humans in other ways. True AC sheets are banned in many countries, though it is possible to find a safer version that uses cellulose instead of asbestos. Other Class 1 building materials include brick, tile and cement. Some carpets also have a Class 1 fire rating.
In personal dwellings, experts recommend using materials with a Class 1 rating, but it isn't mandatory. In the United States, public buildings such as nursing homes, prisons, schools and hospitals must conform to the highest fire-safety standards and are often required to use Class 1 materials.
Pure wood used straight from the tree has different ratings depending on the type of tree. Some trees have a Class 2, or Class B, fire rating. The wood of most trees has a Class 3, or Class C, rating. Composite materials such as plywood and particle board also fall into the Class 3 category.Learn more about Government & Politics
Motorhome sizes are rated by class, including class A, B and C. Class B motorhomes are the smallest with Class C being the next size up and Class A having the largest models available. The class of a motorhome is also defined by its construction and drive train design.Full Answer >
One advantage of HardiePlank siding is that it has a class A fire rating, which means that it resists fire as well as brick does. Using this siding in a home may reduce the cost of insurance. In addition, this siding resists damage from termites, wood peckers, hail and water. One disadvantage of HardiePlank siding is that its installation process is very difficult, and only an experienced technician can do it.Full Answer >
There are several theories about why fire engines are red. One theory suggests that fire trucks were first painted red back in the 1800s when fire brigades took so much pride in their trucks that they wanted them to stand out and feature the most regal and expensive color, which at the time was red.Full Answer >
A modern four-alarm fire refers to the number of units dispatched to the scene of a fire. Most major cities define a unit as a vehicle such as a fire truck, fuel truck, ladder truck, the department SUV or a civilian vehicle. The exact number of dispatched units and firefighters on the scene varies from department to department and rises as the number of alarms increases.Full Answer >