Columbia, SC (WLTX) -- All middle school football games were canceled Wednesday for Richland Two School District.

The famously hot heat is to blame.

Richland Two athletic trainers used what's called a "Wet Bulb Globe Thermometer" to make the call. News 19 set out to learn more about the device and how it protects athletes across the state.

Wednesday's high was 96 in Columbia. It felt like 97. But how hot is too hot to play?

That's where the Wet Bulb Globe Thermometer comes in.

"It's a device that measures whether or not it's safe enough for our student-athletes to be out there for both practice and competition," said Skip Lax, Associate Commissioner for the South Carolina High School League who specializes in sports medicine health-related issues.

Since last year, all members of the South Carolina High School League are required to use the device before students take the field.

With it, athletic trainers can figure the Wet Bulb Globe Temperature, which measures heat stress in direct sunlight (which takes into account temperature), humidity, wind speed, sun angle and cloud cover (solar radiation).

Trainers and coaches can use the chart below for guidance.

Wet Bulb Globe Temperature Monitoring
South Carolina High School League

If the numbers read between 82 and 92, certain modifications can be made.

We watched Airport High School's football practice last month, where they stripped the shoulder pads because of the scorching heat.

"When it gets to a certain point, we make certain changes such as taking equipment off or shortening the time of practice," said Airport High School Athletic Trainer, George Harkness.

For sports with no equipment, modifications may be additional water breaks or rest breaks.

If the reading is higher than 92.1, practices or games will be canceled.

"During this time of year, you want to try to avoid the times of day where heat and humidity is greatest," said Lax. "So for many that means either practicing or playing their games later in the evening or early in the morning to avoid those periods of extreme heat and humidity."

Last month, a student in Atlanta died after collapsing during basketball drills outside in a heat index well over 110 degrees.

"Unfortunately across our country, and South Carolina is no exception, every year there are heat-related illnesses and in some cases heat-related fatalities that occur with our young athletes," said Lax. "The vast majority of heat-related illnesses are preventable."

Medical experts say proper hydration is key during these summer months.

Richland Two officials say this was the first time they've canceled middle school games district-wide due to sweltering heat.