Bluetooth LE-powered hand sanitization monitoring solution to help healthcare workers improve hygiene compliance after Covid-19 

Nordic Semiconductor today announces that Sani nudge, a Høje Tåstrup, Denmark-based healthcare solutions company, has selected Nordic’s nRF52832 Bluetooth® Low Energy (Bluetooth LE) System-on-Chip (SoC) and its nRF51822 Bluetooth LE SoC to provide the wireless connectivity for its ‘Sani nudge’ hygiene monitoring solution. Developed by Poland-based electronic design firm, Grinn Global, Sani nudge is designed to help healthcare institutions improve hand hygiene compliance and processes, critical as the world looks to quickly recover from the Covid-19 pandemic and mitigate against further outbreaks.

“Before Covid-19 hand hygiene was one of the quality metrics ranked with the least importance and healthcare workers saw it more as a task that ‘just had to be done’,” says Dr. Marco Bo Hansen, Medical Director, Sani nudge. “Now in the eye of the hurricane hand hygiene compliance is at the top of the quality list.”

In operation the nRF52832 SoC-powered ‘Sani sensor’ is fitted to new and existing gel, soap and foam hand sanitizer dispensers that are placed in key ‘hygiene zones’, for example at patients beds in healthcare facilities or at the entrance to a laboratory. Facility staff meanwhile are issued with an nRF51822 SoC-powered ‘Sani ID’ beacon that is attached to their identification badge. 

Whenever a healthcare worker or facility staff member use the dispenser, the Nordic-powered Sani sensor credits the closest staff member’s Sani ID badge with an effective hand hygiene ‘event’. In addition to identifying contact, the device also records the time each healthcare worker spent in proximity to the Sani sensor. This data is relayed to a centralized gateway using Bluetooth LE wireless connectivity provided by the nRF52832 SoC, and in turn sends it to the Cloud via a low power wide area network (LPWAN) protocol.

 

The nRF52832 SoC’s high link budget 2.4GHz radio offers a maximum receive (RX) sensitivity of -96-dBm and a maximum transmit (TX) output of +4-dBm, and a total link budget of >100dBm. Combined with Bluetooth LE’s robust frequency hopping, this enables the Sani sensor to receive and transmit RF signals in challenging healthcare environments where machines are often located.

 

A web-based dashboard provides both employees and management with at-a-glance performance metrics, enabling them to improve compliance, and for management to generate customizable compliance reports to ensure staff are meeting set compliance goals. The data also enables hospital management to track which staff members have been in contact with infected patients and determine who else might also be infected with staff to patient back-tracking data.

 

The Sani sensor is powered by four AA batteries and provides a battery life between replacement of at least 18 months, thanks in part to the ultra low power characteristics of the Nordic SoC. The nRF52832 has been engineered to minimize power consumption with features such as the 2.4GHz radio’s 5.5mA peak RX/TX currents and a fully-automatic power management system. The Sani ID meanwhile is powered by a CR2032 coin cell, that also delivers a battery life in excess of 18 months.

 

Nordic’s nRF52832 multiprotocol SoC combines a 64MHz, 32-bit Arm® Cortex® M4 processor with floating point unit (FPU), with a 2.4GHz multiprotocol radio (supporting Bluetooth 5, ANT™, and proprietary 2.4GHz RF protocol software) featuring -96-dB RX sensitivity, with 512kB Flash memory and 64kB RAM. The nRF52832 SoC is supplied with Nordic’s S132 SoftDevice, a Bluetooth 5-certifed RF software protocol stack for building advanced Bluetooth LE applications. The S132 SoftDevice features Central, Peripheral, Broadcaster and Observer Bluetooth LE roles, and supports up to twenty connections. 

 

Nordic’s nRF51822 is ideally suited for Bluetooth LE and 2.4GHz ultra low power wireless applications. The nRF51822 is built around a 32-bit Arm® Cortex® M0 CPU, 2.4GHz multiprotocol radio, and 256kB/128kB Flash and 32kB/16kB RAM. The SoC is supplied with Nordic’s S130 SoftDevice, a Bluetooth 4.2 qualified concurrent multi-link protocol stack.

 

“From a Sani nudge perspective, it was important that the hardware developers at Grinn Global were familiar with Nordic SoCs and their implementation,” says Morten T. Egholm, CTO, Sani nudge. “They had already developed multiple products with Nordic solutions and had a lot of knowledge of what is possible with Nordic’s SoCs and how to rapidly prototype, test, and implement both hardware and software on the Sani nudge solution.

 

“Beyond that, the Nordic community is aimed at all technical levels—developers, system designers, and non-technical people—and that is great. It makes it easier for everyone to stay updated on what is possible now and into the future with Bluetooth LE. This is essential to me as Sani nudge CTO.”