Blast shutter

From Memory Alpha, the free Star Trek reference

Blast shutters are a feature of the cockpit windows of a Class F shuttlecrafts and Danube-classrunabouts, that can be closed to protect the inhabitants from external threats.

In 2374, after the USS Rubicon entered a subspace compression anomaly, Chief O'Brien closed the blast shutters due to a rise in the phenomenon's gamma radiation. (DS9: "One Little Ship")