RT Journal Article SR Electronic T1 Effect of Pressure on the Sublimation Rate of Ice JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 95 OP 97 VO 40 IS 3 A1 Jennings, Thomas A. YR 1986 UL http://journal.pda.org/content/40/3/95.abstract AB This paper considers the effect that chamber pressure has on the sublimation rate of ice and primary drying time. It is shown that the effect of increasing the chamber pressure results in a decrease rather than an increase in the sublimation as was previously reported. The increase in chamber pressure can increase the heat transfer by the wall of the container and result in an increase in the sublimating area. The increase in the sublimating area may more than offset the decrease in the sublimating rate and lead to a reduction in the primary drying time. Upper and lower chamber pressure limits for the lyophilization process are considered.