Dear Everyone

I am trying to collect  all necessary devices to prepare performance testing. Can you recommend what device type do you use? Do you usually rent it or buy?  For now I have the biggest problem with NO2 and CO.

Also a question... there are very wide measurement range for some devices. As example luxometer is up to 50 000 lux. Such level is extremaly high and we expect to have it below 1000. Is it realy necessary to have such wide range device? In my opinion if my range would be 5000 that would be enough.

Best Regards