Definition , function and function requirements

A door is solid barrier that is fixed in an opening in a wall to hinge , pivot or slide open ( or to close ).

The primary function of a door when open is to allow safe means of access and egress.

Characteristics of doors which provide safe means of access and egress.

• A door opening should be sufficiently wide and high for reasonably comfortable access of people.
• Before selecting a door size , consideration should be given to the width of the corridor in which the door is to be positioned.
• Double left doors are commonly used for access to large spaces or room and for convenience in busy corridors.
• Where the door is an entrance door allowing disabled access , glazed panels should be used.

The functional requirements of doors are specified , relating to both the component parts and the whole of the door sets or assemblies (装配；程序集；集会；衣片)