MDHHS Guidance on Digital Data Loggers

MDHHS Guidance on Digital Data Loggers
This handout provides guidance on digital data loggers. The Michigan Department of Health and Human
and Services (MDHHS) follows the recommendations set forth by the Centers for Disease Control and
Prevention (CDC) on digital data loggers. Thermometers are a critical part of good storage and handling
practice and an accurate temperature history is imperative to effective vaccine management.
Keep These Key Points in Mind
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Digital data loggers come in a variety of shapes, sizes, and styles, with many different features
o Most digital data loggers are battery operated
Digital data loggers are accompanied with special software that is installed on a computer
o Software allows user to set frequency of temperature readings, download data and calculate
temperature averages, minimums and maximums
MDHHS recommends Digital Data Loggers with a detachable probe in a buffered material (e.g.,
glycol) with continuous temperature monitoring capabilities; temperature should be easily readable
from outside of the unit and include CDC’s recommended additional features
Storage Unit Temperatures
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Required temperature ranges for storage units are:
o Refrigerator should maintain temperatures at 35oF to 46oF (2oC to 8oC)
 Aim to stabilize temperature at 40oF (5oC)
o Freezer should maintain temperatures at -58oF to +5oF (-50oC to -15oC)
 Set temperature mid-range to achieve average of about 0°F (-18°C)
Why the Digital Data Logger?
MDHHS recommends the use of digital data loggers because:
 Digital Data Loggers provide a complete history of continuous temperature monitoring of each
storage unit and all temperature excursions are captured
 It is a more accurate and comprehensive way to monitor temperatures
 CDC strongly recommends clinics routinely closed for 2 or more consecutive days with staff not
present to monitor temperatures while closed, use digital data loggers with continuous monitoring
What Features Should a Digital Data Logger Have?
CDC recommends that Digital Data loggers include the following features:
 A detachable probe with glycol buffer with continuous temperature monitoring capabilities
 Temperature should be easily readable from outside of the unit
 Alarm for out-of-range temperatures
 Be capable of showing current temperature as well as minimum and maximum temperatures on an
active display
 Be within +/- 1°F accuracy (+/- 0.5°C)
Resources: CDC Storage and Handling Toolkit, May 2014 at: www.cdc.gov/vaccines/recs/storage/toolkit/default.htm
MDHHS guidance for storage and handling can be found at: www.michigan.gov/immunize
July 16, 2015
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Low battery indicator
Memory stores at least 4,000 readings; device will not write over old data and stops recording when
memory is full
User programmable logging interval (or reading rate) of every 15 minutes
o If no interval setting of 15 minutes, use an interval less than 15 minutes
NUALLY: How Do You Place a Data Logger In a Storage Unit?
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Place probe in storage unit, centrally located directly with vaccines; monitor display should be placed
on outside of storage unit
If you are using a pharmaceutical-grade storage unit there is often a built-in port in wall of unit,
designed to allow probe to enter unit and remain in glycol among vaccines
If your storage unit does not have a built-in port for temperature monitoring, probe should enter
through door of storage unit
o The wire should enter refrigerator/freezer on hinge side high in the corner
o Be careful to monitor wire and ensure that frost does not build up
Key Points to Remember
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VFC providers are required to follow the guidelines within the VFC resource book. The resource
book can be found at www.michigan.gov/vfc
Temperature needs to be assessed and recorded on temperature log by office staff twice daily, along
with maximum and minimum temperatures every morning
o Ensure the minimum and maximum temperature is reset every AM
Digital data loggers and all thermometers must be calibrated with a Certificate of Traceability and
Calibration Testing that is not expired
Data logger data should be downloaded and reviewed weekly
All temperature data should be stored for at least 3 years, including temperature logs
If vaccines are exposed to a temperature excursion, do not discard vaccine! ALWAYS, call the
vaccine manufacturer; if Vaccines for Children (VFC) vaccine is involved, contact your Local Health
Department (LHD) for guidance
Consider an alarm/notification system; these systems alert staff to temperature changes
o Digital Data Loggers do not phone staff to alert of out-of-range temperature
Remember storage units can “die” slowly; if thermostat must be turned colder and colder or you
notice a pattern in temperature data, it may be time to look at equipment
It is important to research, ask questions about any storage equipment you are purchasing
As with other vaccine storage equipment there will be a cost to maintaining the digital data logger
o Cost can vary with equipment you purchase, check with the manufacturer
VFC providers that have received a digital data logger through the VFC program may be required by
their Local Health Department (LHD) to put them into use
Know the resources; review MDHHS guidance & CDC’s Storage and Handling Toolkit for current
information; utilize CDC trainings “You Call the Shots” and “Keys to Handling Your Vaccine
Supply” or MDHHS Immunization Nurse Education (INE) “Vaccine Management” module
For guidance regarding VFC data loggers refer to: “MDHHS Tip Sheet on VFC Digital Data Logger”
and “Tip Sheet for Steps on VFC Data Logger Use” at MDHHS website.
Resources: CDC Storage and Handling Toolkit, May 2014 at: www.cdc.gov/vaccines/recs/storage/toolkit/default.htm
MDHHS guidance for storage and handling can be found at: www.michigan.gov/immunize
July 16, 2015