Not to mention getting grease all over your nice clean black stagehand uniform . .

This is a motorized counter-weighted grand drape curtain system that has no guards on the chain drive. Note that the operation buttons are right UNDER the wire-guided counterweight arbor, too. You can also see that the guide wire on the left is significantly deflected from the guide spool on the arbor carraige, which indicates that the system is misaligned, thus increasing the rate of wear on the guide spool and/or the guide wire. Also, you have to lean over and reach past all of the equipment to get to the power disconnect on the wall.
Excerpt from OSHA Regulations:

1926.307(f) "Gears, sprockets, and chains" -

1926.307(f)(1) "Gears."

Gears shall be guarded in accordance with one of the following methods:

(i) By a complete enclosure; or

(ii) By a standard guard as described in paragraph (o) of this section, at least 7 feet high and extending 6 inches above the mesh point of the gears; or

(iii) By a band guard covering the face of gear and having flanges extended inward beyond the root of the teeth on the exposed side or sides. A disk guard or a complete enclosure to the height of 6 feet shall be required where any portion of the train of gears guarded by a band guard is less than 6 feet from the floor.

1926.307(f)(3) "Sprockets and chains."

All sprocket wheels and chains shall be enclosed unless they are more than 7 feet above the floor or platform.

An ANSI Standard formatted sign is also recommended: