What is a-90 doors?

As an AI language model, I cannot verify whether you meant A-90 doors as some specific model or just a general term. However, here is some general information about A-90 doors:

A-90 is a fire rating classification of doors that can withstand fire for up to 90 minutes. A-90 doors can be made of different materials, including wood, metal, and glass. They are used in commercial, industrial, and residential buildings to provide fire protection and compartmentalization. A-90 doors are tested and certified to meet specific fire safety standards and are often required by building codes in certain applications.

Some features of A-90 doors include:

• Fire resistance for up to 90 minutes
• Intumescent seals to prevent smoke and fire spread
• Heavy-duty construction for added strength and durability
• Tested and certified for compliance with fire safety standards
• Available in various materials, designs, and finishes to meet different needs and preferences

Overall, A-90 doors are an essential component of fire protection systems in buildings, and their installation and maintenance should be taken seriously to ensure the safety of occupants and property.