Survey study on Chinese commercial kitchen exhaust fume systems in Tianjin

Abstract Exhaust fume system plays an important role in ensuring indoor and outdoor environment in the Chinese commercial kitchens (CCKs). To investigate the current status of exhaust fume systems in CCKs (CCKEF), on-site survey of cooking appliances, components of CCKEF including exhaust hoods, purification equipment, exhaust fans, discharge form and replacement air, outdoor grease accumulation, and indoor environment, was conducted in 41 CCKs in Tianjin. Results showed that: (1) the diversity and number of cooking appliances was related to kitchen area. 76.19% of stir-frying stoves were located at the end of the appliance lines. (2) Most of the CCKEFs were composed of wall-mounted canopy hood (94.12%), terminal static purifier (98.04%), centrifugal fan (100%), roof-located discharge (66.67%) and transfer air (100%). 47.06% of canopy hoods were equipped with baffle filters, including 29.41% tube-type, 9.80% plate-type and 7.85% strainer-type. The nameplate purification efficiency of purifiers met the fume emission standard. 81.08% of purifier manufacturers were from Beijing. (3) Outdoor grease accumulation was serious. 72.73% had much or a lot of grease accumulation. Cleaning period and the number of burners were the major influence factors. For systems with over 4 burners, the cleaning period was better within 2 months. (4) 70.8% of chefs were dissatisfied with the thermal comfort in CCKs. Thermal and wet sensation varied with seasons and summer was the most unsatisfactory season. Over 80.0% of chefs felt fumes overflowing and interfering noise. The indoor environment in CCKs needed improvement. Survey results can provide reference for the designing of CCKEF in China.