As most of the country thaws after a deep freeze, workers are dressing for the outside as they’re sitting inside at their desks.

Karen Ericson told The Associated Press, "I'm still shivering," as she wore two long-sleeved shirts, a sweater, a fleece jacket, two scarves and two pairs of socks.

“Living in the Midwest, I’m well-trained to dress warmly and in layers, but this deep freeze has been difficult to endure, especially when I expect to be comfortable - or at least not shivering - inside.”

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Erickson, who is a graphic designer in Des Moines, Iowa, said her office inside was in the mid-60s as the outside temperature hit 19 below zero.

But Iowa residents aren’t alone and frozen at their desks.

Rebecca Miller said her office was barely above 50 while it was 20 or lower outside her Nashville, Tennessee office.

Miller wore two sweaters, a scarf, ear coverings, gloves and a blanket while working.

“But I’m still having a hard time working. I’m shaking cold, and it’s hard to focus. The gloves make it hard to type, and the bulky layers make it difficult to move around,” Miller said.

But why do workers freeze when they’re inside?

One reason is office complexes have centralized heating and cooling systems for the overall building, but aren't necessarily adjustable for individual tenants in a large building, Khee Poh Lam, an architecture professor at Carnegie Mellon University in Pittsburgh, told the AP.

Thermostats are also hidden in difficult-to-reach places in false ceilings or air ducts so workers can’t adjust them.

Some offices can have fake thermostats that appear to give control to workers, but are not tied into any system.

A study in 2012 found that about 40 percent of workers are fine with the office temperatures, but design standards say that the rate should be much higher, and come in at 80 percent.

While many people are focusing on freezing during the winter, many workers complain of too much air conditioning in the summer, or a furnace that works too well, forcing workers to open a window when it’s cold outside.

Experts say that the best working temperature is between 72 and 79 degrees, or 10 degrees higher than what many offices are set at, AP reported.

Click here to read more about how temperature affects worker productivity.

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