This publication provides an introduction to air quality monitoring and control equipment, and auxiliary equipment, for boiler plants. It may interest to mechanical engineers, other professional engineers, and construction managers. Here is what is discussed: 1. AIR QUALITY CONTROL AND MONITORING, 2. AUXILIARY MECHANICAL EQUIPMENT, 3. STEAM DEAERATORS, 4. BOILER FEED PUMPS, 5. CONDENSATE PUMPS, 6. AIR COMPRESSORS, 7. BOILER FEEDWATER TREATMENT, 8. BLOWDOWN TANK, 9. BLOWDOWN HEAT RECOVERY, 10. STEAM COIL AIR HEATER, 11. STEAM COIL DRAIN TANK, 12. FANS, 13. HYDRAULIC ASH HANDLING PUMPS, 14. ELECTRIC COOLING WATER PUMPS, 15. BEARING COOLING WATER HEAT EXCHANGERS, 16. IGNITOR FUEL OIL PUMPS, 17. NITROGEN SYSTEM, 18. CARBON DIOXIDE (CO2) SYSTEM, 19. CHEMICAL FEED PUMPS, 20. LABORATORY, 21. SUMP PUMPS