Steady State Efficiency Charts
It is very important to keep in mind that Steady State Efficiency readings will only be reflective of fuel consumption when the O2, stack temperature and CO readings are within the manufacturer's specifications and when the stack temperature has stabilized.
Always check with the appliance manufacturer to determine the specific acceptable ranges of O2, CO and stack temperature.
Good unit converter program
http://www.webcom.com/~legacysy/convert2/unitconvertIE.html
L.P. and Natural Gas Orifice Sizing Chart
B-Vent Letters Letters from 4 B-Vent manufacturers allowing the drilling of their product for combustion/carbon monoxide/draft testing