Is there an Ozone meter I can purchase so I can know when to safely enter my room after running the BIG BLUE on a timer?

There are certainly Ozone meters on the market that will give you a readout in parts per million (PPM), but there’s no need to spend money on an ozone detection system. Your nose will tell you when it is safe to enter. Ozone has a very distinct smell; if you’ve ever been caught in a lighting storm you will remember an acrid, caustic smell produced by the lightning – that’s ozone. Ozone can also be smelled on fresh photocopies. Ozone smells like pool chlorine. Some people also describe it as having a metallic smell. If you smell ozone you should wait to re-enter the room. If you have an exhaust fan now would be a good time to turn it on. Once the distinct smell of ozone is gone, it is safe to enter.