Fires can be very dangerous and hard to put out. However, two US engineering students have been prototyping a way to put out fires with sound. This is a non-destructive and safe way to extinguish flames.

An article explaining the mechanics of the sound extinguisher http://physicsworld.com/cws/article/news/2015/apr/02/dousing-flames-with-low-frequency-sound-waves

Here is a video showing the 2 students, Seth Robertson and Viet Tran, and their fire eliminating device.

This relates to engineering because it is very complicated to make and takes precise measurements. Also, both of the students are in engineering and they had to make this from scratch.