AAPS PharmSciTech

, Volume 12, Issue 1, pp 331–336 | Cite as

Practical Considerations in the Measurement of the Internal Relative Humidity of Pharmaceutical Packages with Data Loggers

  • Eric D. Nelson
  • Henry Huang
Research Article


The utility of temperature/humidity data loggers are evaluated as a low-cost approach to enrich practical understanding of the actual time dependent humidity that a pharmaceutical product is exposed to. While this approach is found to have significant utility in general, small systematic biases in the measurements due to the presence of the data logger are observed. Taking these biases into account enables more productive extrapolation of measured time/humidity profiles.


data logger humidity moisture stability water activity 



Dr. Rajiv Mahajan and Dr. Rey Chern are thanked for many hours of helpful discussion of the underlying technical significance of water activity and packaging science. Prof. Carl Nelson is thanked for thoughtful feedback and input into the theoretical background discussed in this manuscript.


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Copyright information

© American Association of Pharmaceutical Scientists 2011

Authors and Affiliations

  1. 1.Johnson & Johnson Pharmaceutical Research and DevelopmentRaritanUSA

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