Classification and Difference of Fire Door Grades

Time:2020-03-04 16:03:57Clicks1070Source

Fire door is a kind of door that can meet the requirements of fire resistance stability, integrity and heat insulation in a certain period of time.

Fire doors are mainly located in fire compartment, evacuation stairwells and other fire-proof separation objects with certain fire resistance. Fire doors not only have the function of ordinary doors, but also have the function of preventing the spread of fire and smoke. Fire doors can prevent the spread of fire within a certain period of time and ensure the safety of personnel.


In 2009, the state had a new national standard for fire doors, dividing the fire prevention degree of fire doors into different levels. It is divided into Class A fire door, Class B fire door and Class C fire door.

 


Then why should steel fire doors be divided into these three grades? How is it divided? What is the difference between fire doors of different grades?


First, the division of fire doors 


1. According to the fire resistance limit and heat insulation performance, Class A fire door shall not be less than 1.5 hours; Class B fire doors shall not be less than 1.0 hours; Class C fire door shall not be less than 0.5 hours. We can choose according to different needs, but now Class A and Class B fire doors are widely used. 


2. According to the material classification of fire doors: there are many kinds of fire doors, and the materials used are widely stainless steel fire doors, glass fire doors, steel fire doors, etc.

  

Second, the difference between class a fire door and class b fire door 


1. Material Difference: Different fire prevention materials, the material difference lies in the thickness of the built-in fire prevention rock wool board inside, the thickness of rock wool board for Class A fire doors is 52mm, and the thickness of rock wool board for Class B fire doors is 46 mm. As a result, Class A fire doors have longer fire prevention time than Class B fire doors, and the fire prevention performance of Class A fire doors is better. 


2. Difference of uses: Class A fire doors are generally used in important fire exits such as machine rooms, warehouses, oil depots and flammable and explosive public places, while Class B fire doors are generally used in more common fire exits such as some common buildings. The use of Class B fire doors is wider than that of Class A fire doors.

 
In addition, in the actual production process, the same type of fire doors, manufacturers use the same materials. For the same labor, the same materials and the cost paid by the fire door manufacturers are all the same (quotation format and precautions for fire doors).

In the process of production, the only difference is the amount of internal filling materials. If more fire-proof materials are filled, the fire-proof door will have a higher fire-proof rating, while if less filling materials are used, the rating will drop. Therefore, the small price difference among different grades of steel fire doors arises from here.