暖通空调应用媒的安全.pptVIP

“The alternative refrigerants are actually safer than the refrigerants they replace.”“新的制冷剂比被替代的制冷剂更安全” U.S. EPA 美国环保署 Are Toxicity and Safety the Same Thing? 1 lb lead (Pb) 1 lb lead (Pb) Indentical Toxicity 1 Lb lead Block 1 Lb lead Powder Very different safety risks ASHRAE Standard 34 Classifications Only uses chronic toxicity to determine safety Does not indicate that “B” chemicals are toxic Likelihood of reaching the 400 ppm is not considered American Industrial Hygiene Association Workplace Environmental Exposure Limit (WEEL) set at 50 ppm for R-123 R-123’s AEL 10 ppm 30 ppm 50 ppm 1991 1993 1997 Refrigerant Safety Data Summary Refrigerant Selection “He reasoned if he could find a suitable organic compound, which was a liquid at ordinary temperatures and atmospheric pressure, the system would operate under a vacuum and any leakage would be air into the machine instead of refrigerant out. Such a machine would be safe to operate in theatres and other areas where people congregate,and the need for cooling is great.” R-11, R-123 “Recollections of Willis H. Carrier,” ASHRAE Journal, October 1994,Carlyle M. Ashley lliedSignal Honeywell GSA Code Writing Agencies U.S. AIR FORCE DU PONT CHEMICAL Naval Facilities ALL STATE AGENCIES ALL FEDERAL AGENCIES Army Corp of Engineers ICI Chemical Johnson Controls YORK H R A E A S A Lower AEL is an indication of Relative Toxicity, not Relative Safety There is a lower risk of getting to the lower AEL numbers with lower pressure refrigerant than the higher AEL numbers with a higher pressure refrigerant. Can Exposure to Refrigerants Cause Tumors? Summary of PAFT Testing Results for R-123 HCFC-123 has low acute dermal and inhalation toxicity. HCFC-123 caused an increased incidence of benign, but not life-threatening, tumors in animals following long-term exposure. HCFC-123 is not a developmental toxicant. HCFC-123 does not affect reproductive performance. HCFC-123 is not genotoxic. Programme for Alternative Fluorocarbon