STOCKTON, Calif. — Utility worker Clarence Johnson began his Thursday at 7 a.m. in order to get a jump on what he knew was coming.

The temperature in Stockton was forecast for a high of 106 degrees.

"Day after day it can wear on you," said Johnson, finishing up his work laying underground gas line in downtown Stockton.

With 14 years on the job, Johnson knows what he needs to do to keep his cool.

"Basically stay hydrated, wear your protective equipment and basically cycle off, give each other breaks," he said.

It's good advice when temperatures soar, increasing the risk for heat-related illnesses. A high body temperature of 103 degrees or more can signal heat stroke, according to San Joaquin County Public Health Officer Dr. Kismet Baldwin.

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"Nausea, vomiting, headaches. You can also have ultra-mental status so maybe the person or yourself is confused or agitated," she said. "And then, all the way at the extreme end of that you can lose consciousness." 

In 2015, the latest year of statistics for heat stroke deaths, 335 people died in the United States, according to the Centers for Disease Control and Prevention.

And what should you do if someone is suffering from potentially deadly heat stroke?

"You should... call 911. That's the first thing to do. And then, try to get yourself or that person into a cooler environment. You can use some cool cloths or a cool bath," Baldwin said.

For Johnson, when it comes to the sun, he says his co-workers always have his back.

"If they see somebody that looks like they're getting overheated, they'll tap them on the shoulder and check on you and see how you're doing and make sure you're OK," he said.

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