From the outside of our new hospital, one of the first things people notice are the windows. Lots of them. That’s because every patient room has its own large window measuring 8 feet, 11 ½ inches x 11 feet, 10 ⅞ inches.

During the planning process, patients and families conveyed that windows were important to them. After all, windows let in natural light, making rooms more cheerful. They also offer views of nature and the surrounding area, providing a more home-like feel. Studies show that natural light can aid the healing process, too.

Deciding to incorporate windows was easy; choosing the right ones required time and effort. Low-iron glass was picked for its clarity. Designers also needed to ensure that the glass would block out harmful UV rays. Natural light was a plus, but there had to be a way to keep it from disrupting patients’ sleep during the day.

Then, in the midst of planning our new children’s hospital, a tornado struck Joplin, Missouri. A hospital there took a direct hit, and damage was significant. As a result, planners decided to ensure that the windows of our new hospital were the most durable available. The glass in each window weighs 1,780 pounds, or nearly one ton. And that’s only the glass. A two-inch sandwich of glass, ballistic plastic, and air comprises each window.

Our construction team worked with certified testing facilities to measure the strength of our windows. Before testing began, a consulting firm analyzed tracks of tornados in Iowa City from 1950 until 2010. They evaluated the speed and direction of winds in relation to the shape and location of the new children’s hospital.

Next, rigorous testing was conducted in two different states. An airplane engine was used for a water penetration test. It directed significant pressure on the exterior of the window. While pressure was applied, hoses sprayed water towards the window. This test was designed to ensure that the windows were waterproof, even during a severe storm.

A second test involved projecting a 2 x 4 piece of lumber from a specially configured cannon at the window. The speed at which the wood traveled simulated wind speeds up to 249 miles per hour. That equates to the wind speed of an EF3 tornado. The goal was to ensure that the glass, although damaged, would not shatter completely, causing harm to anyone in its path.

The testing was a success. The windows are strong enough to withstand simulated EF3 tornado conditions. For added precaution, each patient room window is equipped with two shades. One is a complete blackout shade; a second one allows some light in. Patients can adjust both shades to meet their needs. In case of an emergency, one button can lower both shades in every room to provide added protection to all those inside our new children’s hospital.