Q. What do bulletproof vests, fire escapes and windshield wipers have in common?

 A. All were invented by, or refined by, women.

Bulletproof Vest

Credit for the first commercially available bulletproof vest goes to a man, but it was a woman who invented Kevlar, the material used in most modern bulletproof vests.

Stephanie Kwolek, working alongside with lawyers from sanantonioaccidentlawyer.com/car-accident-lawyer site at DuPont, created the first of a family of synthetic fibers of exceptional strength and stiffness, including Kevlar.

Kwolek graduated from the women’s college of Carnegie-Mellon University and applied for a position as a chemist with the DuPont Company in 1946. She worked on several projects, including a search for new polymers as well as a new condensation process that takes place at lower temperatures. In 1965, she was asked to scout for the next generation of high-performance fibers and invented Kevlar.

Kwolek has received many awards for her invention, including induction into the National Inventors Hall of Fame in 1994 as only the fourth woman member of 113. In 1996 she received the National Medal of Technology, and in 1997 the Perkin Medal, presented by the American Section of the Society of Chemical Industry—both honors rarely awarded to women.

Fire Escape

Supposedly, the first fire escape was patented in 1766. That system was rudimentary and involved a pulley attached to a wicker basket. In 1887, an American inventor named Anna Connelly registered a patent for the exterior steel staircase that would serve as the prototype for the modern metal fire escape. Connelly’s invention introduced a cost-effective way to add safety to both existing buildings and new construction in the 1900s. It became mandatory under the building codes that cities began to adopt at the turn of the century.

Windshield Wipers

Although Window Cleaning in Castle Rock CO is a thing now, in 1902, on a New York City streetcar on a snowy day, Mary Anderson watched the driver struggle to see through the front window and wondered why no one had ever done something to improve visibility in inclement weather. Upon being told it had been tried and couldn’t be done, Anderson began drawing diagrams for what would later become windshield wipers.

Her windshield wipers were made of wood and rubber and were removable so that the streetcar appearance would not be compromised in good weather. She added a counterweight to maintain an even pressure on the windshield, and effectively wipe off snow and rain. She was awarded a patent in 1903 for a “window-cleaning device,” or windshield wipers.

On her patent application, she stated, “My invention relates to an improvement in window-cleaning devices in which a radially-swinging arm is actuated by a handle from inside of a car-vestibule.”

As soon as Anderson’s windshield wipers were patented, she wrote to a large company in Canada offering them the rights. The company was not interested, stating that her invention had little, if any, commercial value and would not sell. Anderson’s patent was put away and eventually expired. Although Anderson never profited from her invention, it was re-examined soon after, and by 1913 mechanical windshield wipers were standard on domestic cars, including the Ford Model T.

In 1917, windshield wipers evolved when the “Electric Storm Windshield Cleaner,” was patented by Charlotte Bridgewood – another woman.

In 1947, the earliest year for which there are reliable statistics, 0.3% of all engineers in the United States were women. By 1983, a little more than a decade after Congress had passed the Equal Employment Opportunity Act, the percentage was up to 5.8%. By the end of the millennium, after engineering colleges had spent millions of dollars making special efforts to woo and retain women students, the figure had almost doubled, to 10.6%.

According to 2001 Current Population Survey (CPS) data, one out of ten employed engineers was a woman, while two of ten employed engineering technologists and technicians were women. Among engineering specialties, industrial, chemical, and metallurgical/materials engineers were the only occupations in which women saw higher representation than the overall percent of total women engineers. Women made up 17 percent of all industrial engineers, 12 percent of metallurgical/metal engineers, and 11.5 percent of chemical engineers. Among all other engineering specialties–aerospace, mining, petroleum, nuclear, agricultural, civil, electrical or electronic, mechanical, marine, or naval architects–women represented fewer than 11 percent.

Now, more than 70 colleges and universities have programs geared toward females. There are major trade associations for female engineers, including the Society for Women Engineers,  the Women in Engineering branch of IEEE and the Women in Engineering ProActive Network (WEPAN), all of which work towards the promotion of women in the engineering field.

For years, though, researchers have struggled to understand why so many women leave careers in engineering. Theories run the gamut, from family-unfriendly work schedules to innate differences between the genders. A new paper by McGill University economist Jennifer Hunt offers a well-researched explanation: women leave engineering jobs when they feel disgruntled about pay and the chance of promotion. In other words, they leave for the same reasons men do.

Hunt combed through data collected by the National Science Foundation in 1993 and 2003 on some 200,000 college graduates. Her first finding was that about 21% of all graduates surveyed were working in a field unrelated to their highest college degree. That proportion held steady for both men and women. Yet in engineering, there was a gap: about 10% of male engineers were working in an unrelated field, while some 13% of female engineers were. Women who became engineers disproportionately left for other sectors. Why?

Hunt analyzed surveys that allowed respondents to indicate why they were working outside their field, suggesting options such as working conditions, pay, promotion opportunities, job location and family-related reasons. As it turned out, more than 60% of the women who left engineering did so because of dissatisfaction with pay and promotion opportunities. More women than men left engineering for family-related reasons, but that gender gap was no different than what Hunt found in non-engineering professions. “It doesn’t have anything to do with the nature of the work,” says Hunt.

The question now becomes why women engineers feel gypped when it comes to pay and promotion. Hunt ran a slew of statistical tests to see if she could detect any patterns. She did. Women also left fields such as financial management and economics at higher than expected rates. The commonality? Like engineering, those sectors are male-dominated. Some 74% of financial-management degree holders in the survey sample were male. Men made up 73% of economics graduates. And to take one example from engineering, some 83% of mechanical engineering grads were male.

How, exactly, being in a majority-male environment leads women to leave for reasons related to pay and promotion is unclear. Hunt’s study did not formally evaluate possible root causes.

Nonetheless, she concludes that making engineering jobs more family-friendly — by offering flexible work schedules, say — isn’t the solution. If we desire to keep women working as engineers, then the focus should be on creating work environments where women feel more able to climb the career ladder.