Don't know about the Canadian rule but, down here if all energized parts are enclosed it is accepted.
Many small panels 8 circuits or less do not have doors.
Alan--
I know a lot of commercial panels I have sold when I worked at the supplier HAD doors, and most of the resi-panels you could order a door kit if you required them.. They are still allowed to be " doorless" as far as I know, and FPE is the only one off the top of my head that has no doors on their residental panels, but has a door kit option availible...
That panel in the picture, was it a "used" panel???? I have only seen FPE panels with that colour enclosure, and that "old style" main breaker (150 - 200A I believe) manufactured in the early to mid 80's... The " black and white" breakers I think came out in the 80's as well, versus the earlier ones like whats in the bottom right corner, that are black handle, black body....
A.D
Once upon a time, an awful lot of panels did not have doors- just a cover that protected you from touching anything inside. This was common with both fuse boxes and early breaker boxes.
I can't say "why" they disappeared... they just did! The NEC is silent on this point- though it is quite possible that NEMA standards would have something to say.
It appears that this might be a Panelboard located backstage at Hustler Magazine's
"Interplanetary Topless Extravagant Contest 2006".
The Image found just below the Panelboard shows last year's winner
Scott35