As the mercury and humidity level race each other upward, keeping cool becomes both more difficult and imperative.

Working outside during a punishing stretch of summer is not for everyone, and those who can take the heat have ways of protecting themselves from the perils of the sun and thermometer.

Mandy Wolford, a Butler Post Office mail carrier, walks 10 to 17 miles per day in Butler and Butler Township.

At this time of year, all carriers have to cover parts of their vacationing coworkers’ routes in addition to their own.

On Thursday, Wolford pounded the pavement on the West End to cover for a vacationing carrier in addition to delivering to her regular mailboxes in the city and township.

“You have to stay hydrated,” she said. “I drink two gallons of water per day.”

Wolford had loosened her official postal shirt and tied a sweatband around her head, which sported a high ponytail.

Luckily, the post office issues shorts for its carriers.

“Hot, humid days like this are brutal,” Wolford said. “You go home and you want to sit down, but if you do, you won’t get your housework done.”

She appreciates her caring customers, many of whom show their kindness on very hot, humid days.

“You just don’t know how much it’s appreciated when there’s a cold bottle of water or Gatorade on the porch for me,” Wolford said. “It makes my day.”

All in all, the trim and fit postal worker wouldn’t trade her job, even on a hot day.

“I look at it this way: I get paid to exercise,” Wolford said. “I’d rather deliver in the heat than the cold.”

Brian Duffield of Export, Westmoreland County, expertly troweled the wet cement poured into a form on Thursday on the corner of Main and Diamond streets as part of the city’s traffic signal replacement program.

Duffield has worked for Bruce and Merrilee’s Electric Co. for 16 years.

“It’s better than being in the office any day,” Duffield said. “The sun is shining and there’s fresh air and it’s beautiful.”

Duffield also counseled staying hydrated to stay upright.

“I drink 15 to 20 bottles of water each day,” he said.

After working outside for 10 hours, Duffield said it’s hard to remain energetic after a cool shower and a meal at home.

“I don’t care what anyone says, working in the heat is hard on the human body,” he said.

Bob Stirling, owner of Stirling Landscape & Nursery in Center Township, said he keeps a refrigerator full of water, flavored water and pop in the nursery so his six-person crew can grab some cold beverages for consumption under the sun.

He recalls five years ago, when a crew member passed out in the heat and had to be taken to the hospital.

“He could not handle the heat,” Stirling recalled. “He moved to Seattle and took an office job.”

Stirling advises his crew members to wear a short-sleeved shirt, sunglasses and a hat when working in the heat.

“And just don’t overwork and overheat,” he said.

Lots of patrons, young and old alike, took advantage of the splash feature, curly slides and diving boards on Thursday at the Alameda Park Pool.

Under the watchful eye of her mother and vigilant lifeguards, Haisley Lynch, 4, splashed around in the shallow end of the cool blue water outfitted in goggles and water wings attached to a life jacket.

“The pool is cool and relaxing,” Haisley said. “I also like the nachos and cheese.”

Her mother, Harmony Hepler, said she meets with family at Alameda Park Pool each Thursday and Saturday.

“The weather is beautiful and I get to spend time with family,” she said. “We get out of the house and make some memories.”

When not at the pool, the family stays cool in the house by building puzzles and playing games.

Summer Andrzejewski, 6, plays on the rock-climbing wall at Alameda Park Pool before jumping off the diving boards to cool down.

She has two other ways of staying cool on hot summer days.

“Ice cream and smoothies,“ Summer said.

Her brother Eli, 7, said the cool, clear pool is his favorite way to beat the summer heat.

“When you jump in, it’s cold at first,” Eli said. “Then you get used to it.”

He called Alameda pool and all its features “awesome.”

“I like swimming and the fast slide,” Eli said.

Rob Mitchell also finds himself at Alameda Park quite often during the week, but not to swim.

Mitchell is works in maintenance for the county parks and recreation department.

On Thursday, he zipped around outside the pool on an oversize riding mower.

“It doesn’t bother me,” Mitchell said of the heat.

He advises using common sense to stay safe during hot and humid weather.

“You have to keep yourself hydrated, and if you get hot, go in the shade,” Mitchell said.

The National Weather Service is predicting highs of 88 degrees both Saturday and Sunday.