The sound level of the signal would be 40 dBHL. The dBHL unit is used to specify sound levels relative to an individual's hearing threshold, while the dBHL unit is used to specify sound levels relative to a standard reference sound pressure level. When the sound level in dBHL is equal to the sound pressure level in dBSL, the sound level of the signal is the same as the signal level presented.
That depends how close you measure to the mouth speaker. The closer - the louder! The distance is very important if you measure with a sound pressure level meter. A conversation in 1 meter distance may have 60 decibels.