Why we need wireguards for lighting fixtures in the vocational shop?
Is there any code requirement? NFPA or OSHA or other codes and
standards.

Howdy mokia-ga,

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Wire guards, or their equivalent, are required by OSHA (Occupational Safety
& Health Administration) regulations.
http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9882

"U.S. Department of Labor
Occupational Safety & Health Administration
...
Regulations (Standards - 29 CFR)
Wiring methods, components, and equipment for general use. - 1910.305
...
1910.305(a)(2)(iii)(F)

Lamps for general illumination shall be protected from accidental contact
or breakage. Protection shall be provided by elevation of at least 7 feet
from normal working surface or by a suitable fixture or lampholder with a
guard."

If you need any clarification, please feel free to ask.


Search strategy:

Google search on: "wire lamp guards" OSHA
://www.google.com/search?q=%22wire+lamp+guards%22+OSHA

Google search on: "accidental contact or breakage" OSHA
://www.google.com/search?q=%22accidental+contact+or+breakage%22+OSHA

Looking Forward, denco-ga - Google Answers Researcher