In some earlier postings, it was suggested that a beekeeper breathe through a tube to
keep the exhaled CO2 from attracting of aggravating more aggressive bees such as the
AHB.
 
It would be quite simple to design and build a gas mask that would use LiOH to absorb
the CO2 on the exhale cycle.  The material is used in oxygen rebreathers and medical
equipment, and is supposed to be quite cheap. I think there may be other materails that
could be used to absorb the CO2, but the LiOH does not produce dangerous gas when wet.
 
Just a thought