Abstract-This paper presents a simplified method for absolute
determination of the perfornance correction for air density variations
in a convenient ready to use form. It was developed through
the use of computer analysis of data for 14 widely differing vacuum
cleaner motors. By acknowledging that a 1-percent error in the
vacuum correction factor was acceptable, a single curve was developed.
A wattage correction factor curve was also developed.
Because of the variance in efficiencies between motors, however,
this curve has an error range of 4 5 percent. The curves were then
verified experimentally by more than 1000 tests taken in environmental
and altitude chambers in the ambient range from 50 to
100°F and 24 to 30 inches of mercury barometric pressure.
For a better common understanding, the following are also discussed:
1) factors involved in air density calculations, 2) establishment
of standard reference air density, 3) determination of greater
accuracy correction factor, and 4) means of direct air density
measurement