NORFOLK, Va. (WVEC) -- As brutal as the heat has been out there, it is especially hard for the people who have no choice, like members of the military, who often have to be outside to complete their missions.

By the middle of the day, with the air temperature at 95 degrees, and a heat index of 107, it should come as no surprise that at naval installations throughout the region, black flags came out. It's part of an area-wide tiered warning system.

In this case, if the flag is black, that means all non-mission essential strenuous exercise or physical activity must be restricted.

"Unless it's an operational commitment, and there's no way to get around it, then you really should not be outside working, exercising strenuously," saidNaval Support Activity Hampton Roads Fitness Director Kim Wood

For those who do have work outside, the guidance is to be smart and take it as easy as you can, said Wood.

"You should seek shade when possible, take a break when possible, drink lots of water, two to three cups every fifteen minutes are ideal," she said.

The men and women at the NSA MWR gym were working hard. But it was in air conditioned comfort.

Everyone seemed to have a bottle of water at the ready.

While the Navy is concerned about its sailors as individuals, it is also focused on fulfilling mission, which you can't do if you have a bunch of people falling out because of the heat.

"If we have a large number of people that are out of work, out of pocket, that can impact national security," said Wood.

The bad news, for the Navy and everyone else, is Hampton Roads is looking at at least two more days of this heat wave, until a possible break this weekend. So, there'll likely be more black flags to come.