An employee walked through a darkened hallway and tripped. It came up at a safety meeting and the decision was that the building owner needed to put a motion operated light in the hall.

There are already 3 way switches at both ends of the hall. It seems the motion light is only needed because the employee can't be trusted to turn the light on.

Is it reasonable for employees to not be required to turn lights on when they enter a darkened room?

IMHO, a definite no!

Motion sensors are a good idea, and in most cases can save energy, but just installing them because someone neglected to flip a switch??

Egress lights are required to be illuminated when the building is occupied. That's part on the purpose of "night" lighting

Good point.

The hall is a back entrance to the building which the employee was accessing after hours. During normal hours, the lights are left on. The rest of the building does have night lights.

Egress lights need not be illuminated just because the building is occupied. They're only required to operate when the power fails.

Reno,
You are refering to emergency lighting, to illuminate the egress path to the public way. Commonly via battery, some on a emergency generaator, occasionally both.

Keep in mind the OP is in Canada,

As the hall is described as a 'back door' it may be considered as a 'exit' which would require an exit sign & em. Lighting. Depending on the use/occupancy general illumination may be required. (USA general regs)

Battery units are powered 24/7, may be on the nite light circ., may be on the local lighting circuit before switch, or may be on a dedicated circuit if 3 or more lighting circuits in one open area.

I do not know the Canadian codes, but they may be similar.

I'd have to agree with Hotline here.
The idea of a need to provide a motion detector, just because an employee (who should know where the light switch is) tripped, is bordering on the rediculous.

Just another example of that old adage...

"You can't fix stupid"

I may be late with this response but why not add the motion sensitive switches, those are pretty cool ..

Mark:
The point of the OP was IF the motion is required.

As there are switch locations at both means of entering the area, there is no issue.

A motion may be installed, but it would be a design issue, ad not 'code' required.

The subject drifted into egress lighting.