by Andy Slote - Dec 01 2021
As the threat from COVID-19 continues to persist, close contact between people remains a concern for virus transmission. Internet of Things solutions can detect and alert human activity in indoor spaces, providing valuable information for beneficial policies and strategies. Ideally, any implementation should be sensitive to privacy concerns for both detection and use of the data.
Of course, the number of people within a particular space is significant. Occupancy level measurement can use different technologies like infrared sensing, for example. Another way is to install monitoring devices at entry and exit points to a building or room, keeping count as the crowd grows. Determining a limit with good enforcement might make the venue safer.
Focusing only on occupancy, though, assumes that all similar-sized indoor spaces are equal. It also doesn’t address the closeness of interactions, which may also be a threat. We know the impracticality of equipping everyone with proximity alarms, triggering when someone gets too close. In addition, the acceptance rate of this kind of monitoring would be zero in most places.
For airborne viruses, a sensor able to detect the presence would be a game-changer. A complete monitoring capability would be more helpful, possibly with a “heat map” showing where the danger zones exist. Unfortunately, there are currently no devices capable of detecting the presence and levels of Covid-19 in the air.
There is, however, a case for overall indoor air quality being a focus. And, if we can’t detect the virus, is there another substance in the air that can tell us something about the climate in a room, potentially providing actionable data?
Evidence shows the level of carbon dioxide (CO²) can be one of these valuable data points. As humans fill a room, the amount in the air naturally rises due to exhalation. In addition to the number of occupants, a low exchange rate of fresh for stale air will contribute to this escalation. So, the CO² level indicates an environment possibly enabling Covid-19 to spread rather than a high virus presence.
An IoT indoor air quality monitoring solution with CO² sensing can provide continuous monitoring, alerts when it reaches a specified level, and historical data with relationships to specific events or times of the day. An alert could be another trigger to limit the size of the crowd, but there are other potential immediate and longer-term mitigations. For example, opening doors and windows may be possible in some situations. More importantly, the data could trigger an evaluation of the HVAC system to identify changes to improve the indoor climate permanently.
In addition to potentially limiting the spread of Covid-19, these responses to high CO² can create a better environment for occupants. For example, high levels can make people drowsy or cause headaches. Extremely high levels can be more impactful to health.
Adding other sensors can improve things even more, providing detection of:
As with any IoT project, a good solution design is critical. Sensors need to be the correct type with sufficient levels of accuracy. Proper placement in the monitored spaces with the right connectivity to ensure available data is also essential. Finally, turning the data into useful information with optimal visualization for users makes it a beneficial capability with a positive impact on the health of everyone involved.|