Accesses air % in boiler?
Power plant boilers normally run about 10 to 20 percent excess air. Natural gas-fired boilers may run as low as 5 percent excess air. Pulverized coal-fired boilers may run with 20 percent excess air. Gas turbines runs very lean with up to 300 percent excess air. But actually it depends on the fuel consumption rate and the output rate of the boiler and is controlled precisely by damper.
