IRON MOUNTAIN -- All over the U.P., most people have been venturing outside only if they have to.  In the kind of cold we've been facing recently, safety actually becomes an issue.  Freezing temperatures had schools and other area businesses shut down on Thursday.

Empty parking lots, canceled classes, deserted ski slopes--the cold weather has put a freeze on many activities in the Iron Mountain area.  Pine Mountain Ski Resort was shut down due to the safety risks involved in operating in extreme temperatures.

"At nine degrees below zero, a 25-mile-per-hour wind translates to roughly 30 to 40 degrees below zero," said hill manager, Charlie Hassell.  "You're looking at freezing facial tissue in no time at all; less than a minute."

The ski hill is open during below-zero weather, however, one major consideration prompted their decision to shut down on Thursday:  the windchill.  Arctic windchills were also the reason behind shutting down area schools.

If you do have to go out in freezing weather, bundle up and make sure that you have a hat on, since 70 to 80 percent of body heat escapes through the scalp.  If you happen to get wet, change into dry clothing immediately to avoid hypothermia.  Employees at the Iron Mountain Department of Public Works suggest carrying a spare set of clothing with you.

It's not just people that suffer from the cold, however.  At D&L Plumbing Heating & Air Conditioning, business has been booming due to broken furnaces and frozen pipes.

There are some simple ways to prevent these problems.

"Even clothes or anything, boots, keep them away from registers and especially the return air so you have that full flow of air," recommended Guy Daugherty, owner of D&L.

Daugherty also suggested leaving cabinet doors open to allow a little more air flow inside to help avoid frozen pipes.