Florida Power & Light Company (FPL) is the third-largest electric utility in the United States. It serves nearly 5 million customer accounts, which is an estimated 10 million people across nearly half of Florida.

"Hurricane Irma is unprecedented by almost every measure – its size, destructive power and slow movement. All 27,000 square miles and 35 counties of our service territory have been impacted by this devastating storm," President and CEO of FPL Eric Silagy said in a Monday news release.

A city worker places stop signs at intersections after Hurricane Irma knocked out power and traffic signals in Marco Island, Fla., Monday, Sept. 11, 2017. (AP Photo/David Goldman)

FPL estimates that there were more than 5 million power outages from Hurricane Irma. FPL estimates that 4.4 million customers were impacted by the storm and that some customers may have experienced more than one outage, according to the news release.

FPL has launched a massive effort to restore power to those impacted by Irma. There are nearly 19,500 FPL employees and workers from other utilities and electrical contracting companies joined in restoration efforts.

There are nearly 30 staging sites activated with restoration crews, trucks and equipment from across the United States and Canada, according to the news release.

Our trucks are rolling by the hundreds with a little help from our friends @FLHSMV. Thank you, Florida Highway Patrol! pic.twitter.com/mpl0zYAFrP

— FPL (@insideFPL) September 12, 2017

18,000+ workers are restoring power - every hour of every day – even as we assess full damage of #Irma pic.twitter.com/BC9MWUzDg2

— FPL (@insideFPL) September 11, 2017

"We have the largest restoration workforce in U.S. history responding to the worst storm in our company's history. Our crews are out restoring power, and every hour of every day more and more people are getting their lights back," Silagy said.

As of the issuing time on the press release, more than 1.1 million customers who were affected by Irma had their service restored.

FPL anticipates that this may be a lengthy restoration effort.

The electric system along Florida's east coast will require more traditional repairs. FPL said in a tweet that they predict it to be repaired by the end of the weekend.

In contrast, much of the electric system in southwestern Florida will require a complete rebuild. The rebuild could take a few weeks. FPL said in a tweet that they predict it to be restored by Sept. 22.

Utility groups from regions across the United States and Canada are traveling to Florida to help in this time of crisis. There are workers from about 30 states.

Our crews are fueling up in Orlando and headed to Lake Worth, FL to help @insideFPL restore power to millions of customers. #HurricaneIrma pic.twitter.com/b6pusPWb6w

— Consumers Energy (@ConsumersEnergy) September 11, 2017

Exelon sent more than 1,800 employees and contractors from its six utilities to assist in the massive power restoration effort. Exelon also donated an additional $100,000 for Harvey and Irma relief, which brings the total to $450,000, according to a news release.

“Exelon is committed to participating in the mutual assistance network to make sure that utility crews are there when help is needed,” Exelon President and CEO Chris Crane said in the news release.

“We are committed to being of service and putting our resources to work to assist our fellow utilities and communities in need.” #Irma2017 https://t.co/Q1gY3vUE42

— Exelon Corporation (@Exelon) September 10, 2017

In the event of an extended power outage, such as in the case of Irma, having a generator at home can be a huge advantage. But if used improperly, the devices can cause serious harm or even kill.

A Titusville family of eight and their two dogs were treated for carbon monoxide poisoning after keeping their generator inside a closed garage, according to Titusville officials.

Twenty more people, including five children, were taken to area hospitals Tuesday morning after a hazmat situation, as a precaution because of the threat of carbon monoxide poisoning due to the proximity of a generator, according to the Bonita Springs Fire Rescue.

One person died and three more people were treated for carbon monoxide poisoning from a generator inside a home, according to the Daytona Beach Fire Department.

Three people died and four more where injured due to carbon monoxide poisoning, according to the Orange County Sheriff's Office.

AccuWeather provides a number of safety tips to prevent these tragedies. These tips include keeping your generator at least 30 feet away from your home and only operating your generator in dry areas.