Infection Prevention and Control (CAMCAH / Critical Access Hospitals)
Q. My organization uses the “penny in a cup” method for monitoring refrigerator/freezer temperature. Does this meet Joint Commission standards?
"Penny in a Cup"
Current | November 28, 2008
A. Healthcare organizations commonly freeze a small cup of water, place a penny on top of the ice, and keep the "penny in a cup" in the freezer compartment of a refrigerator/freezer unit. They surmise that as long as the penny remains on top, indicating that the ice has not melted, the refrigerator/freezer unit has remained within an acceptable temperature range.
The Joint Commission standards recognize the importance of maintaining appropriate temperature ranges for both medications and nutritional products. The integrity and potency of medications, as well as the safety of nutritional products, can be compromised by temperatures that exceed recommended ranges. The "penny in a cup" method will not be meet the intent of Joint Commission standards for the following reasons:
- Sensitivity-The sensitivity of this method is not proven. The temperature range of the refrigerator or freezer may be significantly above recommendations before the penny sinks. Furthermore, the penny will not recognize temperatures below the desired range.
- Variability-The design of the refrigerator/freezer unit, as well as its maintenance, may vary significantly. A large unit, or one with a well-insulated freezer compartment, may keep the penny afloat even though the refrigerator becomes too warm. Also, surveyors commonly find freezer compartments packed with inches of ice because they have not been adequately defrosted. This thick layer of freezer ice could protect the "penny in a cup" from warming refrigerator temperatures.
- Availability of technology-Reliable alarming and recording thermometers are readily available. Also, wireless thermometers are also available that send updates to a central computer. Other options such as min/max thermometers should also be considered.