We were staring at the graph on the screen. We looked at each other. It was bad…much worse than we had expected.
As an experienced R&D engineer with decades of experience, I was used to looking at performance data, analyzing it, interpreting it and giving the results to my clients without judgement, for them to use to evaluate and improve designs. But this was different, these results actually impacted me personally.
We had just finished analyzing and plotting the data recorded over days of motorcycle ride testing. Our goal had been to accurately measure and record the sounds inside a motorcycle helmet. From these recordings, we can derive in-ear sound pressure levels (SPL) – the actual physical measurement of the pressure intensity of the sound wave.
Measuring SPL is a fairly simple idea, but it has to be carefully measured and the microphones, recording devices etc. must be carefully calibrated and traceable back to a standardized pressure.
For this particular data set, I had been the test rider – so the helmet, and the bike were mine. Seeing SPLs that were so extreme really hit home for me, as this was my ride and my ears that were being affected by the intense sound levels.
While this data confirmed our worst fears of our own personal hearing damage, it also gave us the necessary information to design a system that would be able to counter and protect the rider’s hearing.