People argue that women aren't strong enough to be firefighters. Here's why they're wrong.

On April 18, five women graduated from New York City’s Fire Academy.

This brings the number of women serving in the Fire Department of New York to 72, the highest in its history.

The FDNY’s 2018 graduating class also includes the first son to follow his mother into the profession. She was one of the 41 women hired in 1982 after the department lost a gender discrimination lawsuit and was ordered to add qualified women to the force.

Despite these milestones, women still make up less than 1% of New York’s 11,000 firefighters.

The city trails Minneapolis, San Francisco, Seattle, and Miami, where in recent years, fire squads have been more than 10% female. The national average hovers around 5%.

Approximately 10,300 women nationwide worked as full-time firefighters in 2016, according to the most recent data available from the Department of Labor. In 1983, there were just 1,700.

I interviewed over 100 female firefighters for an academic study of women in traditionally male industries. My research reveals how women are changing firehouse culture and transforming how Americans see heroism.

Though women have only served in the FDNY since 1982, they have been putting out fires in the U.S. for 200 years.

In 1815, Molly Williams joined New York City’s Oceanus Engine Company No. 11. Williams was a black woman enslaved by a wealthy New York merchant who volunteered at the firehouse. Williams would accompany the merchant to the station to cook and clean for the all-white, all-male crew.

One evening, the fire alarm rang but the men were incapacitated by the flu. So Williams grabbed the hand-pumped hose and answered the call alone. Her strength so impressed the men that they offered her a job.

In 1926, 50-year-old Emma Vernell became New Jersey’s first female firefighter when her husband died in the line of duty. Many more women took their husbands’ places in America’s volunteer fire service during World War II. By the mid-1940s, two Illinois military fire departments were “manned” entirely by women.

But the profession really opened up to women after the passage of the 1964 Civil Rights Act, which made it illegal for employers to discriminate against applicants based on sex, race, religion, or nationality.

Despite this history, I still hear claims that affirmative action for female firefighters is diluting standards and putting communities at risk.

Even my liberal colleagues have asked me whether women can really carry an unconscious victim out of a fire while wearing 100 pounds of gear.

The answer is yes. In 2008, almost 70% of all aspiring female firefighters passed the national Candidate Physical Abilities Test, which tests for endurance, strength and cardiovascular health. The same year, 75% of male applicants passed.

Female success rates rise when departments offer specialized preparation programs for women to work out together, get hands-on experience with firefighting equipment, and follow individualized strength-training routines.

Critics have suggested to me that there aren’t more female firefighters because women are not interested in such a dangerous and “dirty” job. Yet women are much better represented in fields that require a comparable level of strength and stamina, including drywall installation, logging, and welding (though they remain a minority).

So why are just 5% of firefighters female?

Based on research on gender integration in the U.S. military, I believe the main obstacle facing women in firefighting is its traditional culture.

Like soldiers, firefighters are viewed as proud warriors working on dangerous front lines. That image comes with powerful stereotypes about who’s best suited to do the work. Female soldiers and firefighters both challenge a cultural standard that men are heroes and women are onlookers or even victims.

The military first added women to its ranks in 1948. But today, women still account for just 15% of active military personnel.

Firefighting too is a traditional field. Over the past decade, numerous departments have been found guilty of discriminating against applicants of color and ordered to retool entrance testing that had a disparate impact based on race. Women are in some ways even more disruptive newcomers to firefighting because they entirely upend societal gender norms.

Women are also discouraged from pursuing firefighting because those who do face severe harassment on the job.

One woman I interviewed found her oxygen tank drained. Another confided that her male colleagues are so hostile she fears they’ll leave her alone in a fire.

Female firefighters also contend with ill-fitting gear. The long fingers of male gloves affect their grip, they report. Boots and coats are too large. Oversized breathing masks push their loose helmets forward, blocking their vision during fires.

Station houses often lack of private spaces for women, including bathrooms, changing areas and dormitories. In 2016, 34 years after women joined New York City’s fire department, the city boasted that all of its 214 active firehouses finally had gender-separated facilities.

For three decades, some of New York’s bravest went to the bathroom in neighborhood diners. Many others just went ahead and used the men’s room.

Despite what they're up against, female firefighters still succeed.

Several hundred have risen to the level of lieutenant or captain. Another 150 hold the highest rank of fire chief. That includes Chief JoAnne Hayes-White, whose historic 2004 hiring made San Francisco the world’s largest urban fire department led by a woman.

Meanwhile, these women are transforming how Americans imagine heroism.

One Wisconsin firefighter said people are surprised when her all-female crew pulls up to a blaze. But, she told me, “No one cares if you’re a woman when their house is on fire.”

A woman in San Francisco said she intentionally stands outside the station during down time so that neighborhood children realize that black women can be firefighters.

“You have to see it to be it,” she said.

This story originally appeared on The Conversation and is reprinted here with permission.