Width of a fire door vision panel?

[Guest LarryCu]

Is there a standard for the minimum width of a fire door vision panel?

[Tom Sutton]

A particular door leaf design will have a maximum permissible size of glazing aperture based on full-scale test evidence on that specific door construction.

It must not be assumed that this maximum approved size may be automatically applied to another door leaf construction. Each door assembly requires its own specific test evidence, or assessment evidence related to test data.

There is no standard for the minimum width of a fire door vision panel it all depends on the test data when the door set was tested.