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Company name: Africonnect Ltd

Business Sector: World Health

NHDS Product: Messenger 62

Application: Temperature monitoring of freezers containing Malaria vaccines

As research into a suitable vaccine to fight Malaria continues in Ghana, Africa, we had a requirement to provide a freezer monitoring system to ensure vaccines are not destroyed by temperature fluctuations. We approached NHDS who have provided a bespoke solution that informs research centre staff immediately, via sms text messages to their existing GSM phones, if the freezers deviate by +/-5C from their normal operating temperature of 80C. With staff located 30 minutes from the centre it is critical that the alarm information is both accurate and in real time. Dick Elleray, Africonnect Ltd.

Freezer Monitor


To monitor temperatures of medical freezers containing malaria vaccines and a refrigerator containing blood samples. If the freezer temperature, usually set at between 75C and 80c, rises by more than 5C it is recorded by the Messenger M62 and an alarm is sent as an SMS text message to the research staffs existing mobile phones. The information received is date and time stamped and also reports which freezer has an alarmed state. The refrigerator had no temperature probes present therefore a "fridge top" box was designed and built to continually record both the temperature in the fridge and freezer compartments. The unit has a user interface to allow configuration of alarm thresholds. When an alarmed condition is present this is recorded by the Messenger M62 and forwarded to staff mobiles as with the freezers. The Messenger unit also reports mains power failure and restoration.

Operational Benefits Reduced risk to patients of ineffective vaccination Remote staff immediately informed of temperature alarms and power failure Existing mobile phones are utilized Only one Messenger M62 unit required for up to eight freezers