Nonfunctional or poorly performing vaccine cold chain equipment (CCE) can put temperature-sensitive vaccines at risk of potency damage. PATH conducted a multicountry assessment of CCE to better understand how and why WHO-prequalified vaccine refrigerators fail to meet WHO PQS temperature performance requirements outside of laboratory testing conditions.

This document details the assessment methodology that was used by PATH to gather a comprehensive set of inventory, physical, and functional data on vaccine refrigerators and freezers, including the data fields recorded, the procedure used to collect these data, and the equipment required to do so. This methodology is most suitable for the systematic collection of data from multiple refrigerators when statistical analysis of CCE is of interest. It may also be useful in assessing immediate or root causes of failure, assisting in repair and maintenance, evaluating equipment design and longevity, or other purposes.