NIOSH provides a free sound level meter app which can be used to determine if your testing environment should be compliant. You can download the app from the app store on an iOS device.
Using the app, measure the ambient noise in your room. If the number in the LAeq [dB] field is under 45, your room should be ok for testing.
Measurements of 45dB or less do not guarantee that a room will be compliant when third octave band measurements are taken with a type 2 sound level meter. In addition, rooms with values greater than 45dB may be compliant when third octave band measurements are taken with a type 2 sound level meter. The LAeq measurement should simply be taken to generally determine if a room could be considered for testing. Final verification will have to be done with the Salux Calibration device prior to testing daily.
If you’re having trouble finding a room with an acceptable ambient noise level, move to a room without excessive HVAC noise and away from any nearby machinery. Conference rooms and guest offices are usually good choices.