Word for "distance in time"

When referring to 'distance in time', the best word is:

Interval

There is also:

Period
Spell

duration or period

The duration between building maintenance dates is about ten days.

or

The period between building maintenance dates is about ten days.

Alternatives include:

• time
• time span
• interval
• term
• spell
• interim
• tide
• space
• stretch
• spread
• gap
• interlude
• opening
• pause

Wouldn't time do in this case?

As in time between building maintenance dates is about ten days.

Update: If it is a column title and not a sentence as the OP mentioned in the comments, either Interval or Time Interval would be a better choice.

"timespan" ?