Fire Resistance Rating of Container Houses

The fire resistance rating of container houses depends on their construction materials. Compliant products should meet Class A fire resistance standards, while illegally modified houses may not meet these standards.

Fire Resistance Ratings of Compliant Container Houses

According to fire safety regulations, container houses used for residential or office purposes must use Class A fire-resistant panels (such as rock wool panels, fire-resistant cotton, and magnesium oxide boards). For example:

• Rock wool panels/fire-resistant cotton: These materials achieve Class A non-combustible standards, with high fire resistance limits, effectively preventing combustion and slowing the spread of fire.
• Magnesium oxide boards: Made from magnesium oxide cement and glass fibers, these materials meet the Class A1 non-combustible standard of GB8624-2012, with a fire resistance limit of ≥5 hours, smoke toxicity of AQ1 (non-toxic emissions), and structural integrity maintained even at 1350°C.

Fire Safety Issues in Illegally Modified Container Houses

Some illegally modified container houses use flammable sandwich panels such as polystyrene and polyurethane foam to reduce costs, resulting in non-compliant fire resistance ratings and serious safety hazards:

• Rapid combustion: Flammable materials melt and deform at 80°C, causing secondary combustion and rapid fire spread.
• High toxicity: Combustion releases thick black smoke and toxic gases, making it difficult for trapped individuals to escape and increasing the risk of casualties.
• Difficult firefighting: Fire spread can lead to container collapse, and the iron sheet wrapping obstructs water cannon spray, increasing rescue difficulty.

Basis for Determining Fire Resistance Ratings

The fire resistance rating of container houses is determined by the combustion performance and fire resistance limits of building components (such as walls, floors, and roofs), and must comply with the requirements of the Code for Fire Protection Design of Buildings (GB 50016—2014):

• Class A non-combustible materials: Such as rock wool and magnesium oxide boards, with high fire resistance limits, suitable for crowded places.
• Class B1 difficult-to-ignite materials: Some compliant products may use these, but their use scenarios must be strictly restricted.
• Class B2/B3 combustible/flammable materials: Houses using these materials illegally have extremely low fire resistance ratings and are strictly prohibited for residential use.