Types of Occupancy Sensors for the Workplace

The adoption of sensor technology within the real estate industry is rapidly growing and with good reason. Not only do sensors help monitor space occupancy, but they also help property managers and workplace tenants improve the utilization of space, assets, and energy, increasing workplace productivity, improving safety, boosting employee experience, and bettering the bottom line.

The accurate and reliable data, which sensors can provide on building usage, is one potential solution for increasing workplace efficiency from the 40% office utilization we saw in 2018.

With interest in traditional office spaces dwindling, employers and building management companies are attempting to make their work environments more dynamic by the day. This effort is being driven by trends in Activity Based Working (ABW), shared spaces, and free addressing. All of these strategies necessitate obtaining better data on how buildings are used day-to-day and new technologies to unlock this data.

It’s not a small problem. For large corporations, the annual spend on real estate represents their second largest cost center (only trailing employee salaries). And with the annual price of leasing and operating corporate space continuing to rise, managing this cost is an ever-present challenge.

Over the last few years, numerous sensor technology vendors have entered the market with a variety of different sensor-based solutions to meet this growing need, ranging from PIR motion sensors, BLE beacons, WiFi AP data, badge scans, and more modern computer vision-based technologies.

The technology is complex, and with many different options on the market, it’s important to understand the capabilities (and gaps) with each solution type. Like anything, it’s about matching the best tool for the job.

Before setting out on your own buyer journey with sensor technology, our recommendation is to start with a list of specific goals.

• What, exactly, are you looking to accomplish with sensors?
• Are you looking for analytics or occupant experience?
• Is the building a new construction environment, or existing space?
• Are you looking to monitor conference rooms, desks, lounge areas, entrances/exits, or all of the above?
• Or are you more concerned about data quality/accuracy?
• And finally, what the heck are you planning to do with all his valuable data?  

From vision sensors to lighting-integrated sensors, each technology has pluses and minuses and is designed to address different needs. Below, we lay out the key categories that we are seeing in the market and where they are or are not applicable.

What is an Occupancy Sensor?

Occupancy sensors work by detecting motion and changes in an environment, showing workplace strategists how much or how little each space in an office is used. Workplace sensors can gather occupancy data from individual desks up to entire buildings, and they can help reduce costs related to real estate and energy expenditures — which benefits the environment, too.

Vision Sensors

True to their name, vision sensors replace a camera for vision with a sensor to take low-resolution images that report precisely how many people or even assets (desks, printers, etc.) are actively in a room.

These sensors are composed of a computer processor, replacing the need for a camera as it detects objects that have variable positions or shapes. This drastically lowers the cost of needing a high priced camera system. It also mitigates privacy issues by only utilizing low-resolution imagery on the devices themselves.

The VergeSense sensor-as-a-service platform is made up of these types of sensors. Equipped with the latest computer vision and AI technology, these sensors not only go beyond occupancy by measuring an accurate person count for any space but the same hardware can also be expanded to deliver future use-cases with new AI models.

Combined with analytics, vision sensors are optimal for knowing how many people are in, or assets are being used within, a room at any given moment. For instance, if there’s an emergency that impacts a building, these sensors can instantly pull a people count of every person in the building for first responders. These sensors also have the power to drive facility optimization by classifying spaces on how messy they are rather than just having a team clean all spaces every night.

There are two categories of products in this area —  wireless vision sensors (battery operated), and wired/PoE options, which get power from a cable in a similar way to how a wireless router is installed. For existing buildings, wireless sensors are typically the best option, as they can be deployed rapidly without the need for accessing their location based on a nearby power source. Learn how wireless IoT sensors can provide data-driven insights to the workplace.

BLE Beacons

Bluetooth Low Energy (BLE) beacons aren’t to be confused with the original Bluetooth beacon. When you typically think of Bluetooth, you may picture your AirPods syncing with your iPhone or connecting your cellular device to your automobile. Those instances use the classic Bluetooth beacon, and it uses a lot of power to transmit over long ranges.

BLE beacons don’t use as much power as the classic use case because they only transmit a small amount of data over a short range.

So, how does it work? BLE beacons transmit a universally unique identifier to nearby devices with a compatible application. The connection can be used to track customers, pinpoint where a device is, or even send across push notifications based on location. BLE beacons can help businesses strategize in regards to marketing and help convert potential buyers to actual customers.

What’s extremely important to note here is that the devices being sent the unique identifier have to have a specific application downloaded on it. The functionality is in place for security reasons, so the beacon can’t access everyone’s device with Bluetooth on it.

PIR Occupancy Sensors

When looking to analyze how an entire room is being utilized, passive infrared (PIR) sensors can be a good option. These sensors are mounted on a ceiling and have a wide outlook of the room. Using passive infrared technology, PIR sensors detect heat and movement and have a very high accuracy rate of about 92 percent.

This accuracy rate, however, is decreased when people are stationary for extended periods. That means that while these sensors are great for determining how to optimize the office, they can struggle to detect the specific amount of people in a particular space in real time.

Therefore PIR sensors may not be a great help when it comes to ensuring worker safety during office emergencies or with analyzing specific conference room usage. Compared with vision sensors, PIR occupancy sensors are much less accurate for the coverage area.

Keep in mind that the placement of PIR occupancy sensors is very particular. If you do go the route of using PIR you need to make sure you don’t place the sensors too close to a vent or in direct sunlight because it might misread the heat and movement you’re trying to detect.

PIR Desk Sensors

Desk sensors are used to keep track of how often a desk is being utilized. These sensors typically fall under the PIR technology umbrella and are placed underneath desks to monitor if a person is at the desk through body heat and motion. Desk sensors are linked to Wi-Fi and work in real time, which helps employers to gain valuable information quickly.

The main benefit of these sensors is that they can measure occupancy for such a precise location, whereas occupancy sensors track the entire room. While this can help optimize office spaces, research has shown that some employees are a bit anxious with these sensors under their desks. It’s important to explain to employees what the sensors are used for to try and increase employee comfort.

Ultrasonic Sensors

Ultrasonic sensors emit pulses of ultrasonic waves and measure the reflection of a moving object. They are a type of motion sensor that are used primarily for security purposes. 

Very often, ultrasonic sensors are used as an alternative to PIR sensors in the workplace.

They use sound waves at a higher frequency than humans are able to hear— usually in the range 30kHz to 10MHz. A sound pulse is sent out at a given frequency, and as it bounces off objects in its way, it is reflected and captured by th receiver.

So, if you're in an empty room, the reflections will bounce from the opposite wall and the time taken for the reflection to be received will be in proportion to the distance between the sensor and the wall. If a human enters the room, the pulses will reflect from them and therefore the time taken to receive the reflections will be less. 

Door-Counting Sensors

Door-counting sensors are very similar to desk sensors, except that they track movement through a specific doorway. These are typically used to see how many people are in a room with a single entry and exit point, such as conference rooms.

While these types of sensors work great for say an auditorium where you are tracking the number of people entering or exiting through a single door, they don’t work very well in the modern office given the growing reliance on open concepts that limit the number of doorways.

These sensors can typically be installed overhead or horizontally within door areas and also typically offer both battery powered and wired options. First generation door counting sensors may only track all activity at the door, while most door counting sensors today can monitor both entry and exit to give a real-time count of people in a room (assuming they are tracking each entry/exit point).

Errors are also relatively common, which can be quite frustrating when sifting through the records. Door-counting sensors work best for rooms that have one doorway and are used pretty infrequently.

Lighting-Integrated Sensors

Lighting-integrated sensors control lights based on movement. These are great when it comes to reducing energy costs and increasing sustainability as lights only turn on when there’s movement in the room.

While this doesn’t matter as much for open office spaces, this works amazingly well for conference rooms and executive offices that are not always utilized. These sensors are fantastic for energy savings, but they don’t track the number of people in a space very accurately, which doesn’t help with efforts to optimize office utilization.

So, what will it be? The type of sensor technology you invest in will ultimately come down to your business needs and goals. If your goal is to increase sustainability and cut energy costs, then invest in lighting-integrated sensors. If your goal is to increase workplace engagement by knowing the exact number of people in a room at any given time, then vision sensors are probably the best bet.

How VergeSense Helps

With services such as people counting, desk utilization, and beaconing, VergeSense’s sensors will help you optimize your workplace with our AI-powered utilization analytics. Our sensors are 100 percent wireless and operate independently of your existing IT network. These sensors can be installed in less than a minute and can cover up to 10 desks simultaneously in an open office area. To learn more, go to www.vergesense.com today.