The definition of a confined space can be unclear and confusing.  A confined space is not just an area where it is difficult to move.
When deciding the classification of spaces on a work site you should aim to be:

• Consistent Realistic
• Practical (consult employees)
• Knowledgeable (confined space trained)

Before wasting time debating the classification, identify the potential hazards and decide on realistic controls for the space. Then compare the controls you have selected to the requirements of the confined space regulations... they may be the same.

Some sites use the definition "Restrictive Space".  This is used to describe an area that may become a confined space under certain conditions.

If confined space planning and preparation seems time consuming or too hard, maybe your site procedures need streamlining.  KEEP IT SIMPLE

See Article - aioh_conference_paper