Volume I - Section III - Evaluation of Results and Recommendations 
Page III - 23 
Figure 3.27 Comparison of Mean Cage NH 3 Concentrations (ppm) 
Figure 3.28 Comparison of Mean Breathing Zone NH 3 Concentrations (ppm) 
The NH3 concentrations follow the trends shown by the CO2 concentrations. The 5 ACH NH3 
results are not directly comparable with those for the other flow rates. This is due to the 
extremely low supply discharge temperature 6.6 °C (44 °F) required to extract the heat produced 
by the mice and the change station, which required the moisture content of the air to be reduced 
compared to the other flow rates, the standard value used in the simulations represented well 
over 100 percent humidity. It is also recognised that this low temperature is difficult, if not 
impossible, to achieve in commercial heating and ventilation systems. 
