TWIN FALLS, Idaho (KLIX) – Do not post promotional flyers or signs on utility poles. That’s the message of Idaho Power, according to information provided by the utility company.

“For the safety of our employees who access these structures, protruding nails and other foreign objects left behind can cause injury,” reads information on the company’s website. “Also, according to state codes, it is illegal in Idaho and Oregon [to post anything on utility poles] without prior authorization from the utility.”

The message is clear: the next time you have a garage sale or something else you want to promote, don’t post it on a power pole. That’s a big no-no.