The Guide to Occupancy Sensors

What are occupancy sensors, how do they work and how can you make your building smart?

What are occupancy sensors?

An occupancy sensor is an electronic device that is able to detect motion and recognize when a person has entered a room. There are various occupancy sensing technologies, but the most common are passive infrared, microwave, ultrasonic, and video image processing.

Typically ceiling mounted, the sensors are usually connected to a building's Internet of Things (IoT) network and feed data back to building management systems and booking systems that can automate systems for lighting, HVAC, and ventilation control whilst providing data for occupancy analytics systems to understand desk usage, meeting room efficiency and space utilization.

How do occupancy sensors work?

An occupancy sensor typically works by detecting motion and changes in its environment; each sensing technology does this in a different way. For example:

  • Sensors that use basic passive infrared (PIR) technology detect movement and changes in their field of view. These sensors are simple, providing basic occupied or unoccupied data. A common example of a PIR sensor is a desk sensor that is typically placed on the underside of a desk and is used to detect and report desk occupancy.
  • Ultrasonic sensors emit high-frequency sound waves outside of the human hearing range and use the doppler effect of returning sound waves to detect people.
  • Time of flight infrared sensors use a similar principle as ultrasonic sensors; however, instead of sound, they use infrared light. By emitting invisible infrared light, AI onboard these sensors learns their surroundings and detects changes when people pass by. These are advanced occupancy sensors that count people and can provide accurate data for occupancy levels and space utilization.
  • Camera-based occupancy sensors have a camera onboard for image processing. Typically, the camera is activated to record when motion is detected. Naturally, this type of equipment may trigger security and privacy concerns for occupants.

Advanced type sensors are usually installed in strategic locations to pick up motion in high-traffic or isolated areas. Designed to be discreet, they are typically ceiling-mounted devices that detect individuals and groups entering or exiting a zone – building, floor, room, etc.

The data collected is then transmitted to a cloud-based platform where AI algorithms can calculate real-time occupancy levels and space utilization. From here, reliable data can be integrated with other systems, such as lighting, HVAC, or booking systems when predetermined levels are reached.

What are the best occupancy sensors?

The smart building technology you invest in will largely depend on the needs of your organization. Are you looking to optimize your space utilization, implement desk hoteling, improve energy efficiency, manage your meeting room sizes or enhance employee productivity? 

There are various options on the market, and each offers different levels of data and integration capabilities with varied installation requirements. Accuracy, efficiency, and compliance with data protection policies through collecting anonymous data should be amongst your top priorities when selecting an occupancy sensor

A passive infrared (PIR) sensor, for example, will only tell you whether a zone is occupied or not – not the number of individuals in it. Therefore, this type of sensor is aligned for facilitating desk hoteling. However, it wouldn't be suitable for enabling meeting room management or for understanding space usage for space planning decisions. 

Irisys True Occupancy is a complete building occupancy monitoring solution that provides essential occupancy data for everywhere that matters to you, from desks to rooms and open areas to buildings. 

The solution gives you accurate, real-time, anonymous occupancy data enabling you to:

  • Know when spaces are occupied and how this space is being used.
  • Identify underutilized spaces, such as if you have the right size meeting rooms for the average number of people that use them. 
  • Identify high footfall locations and ensure that these zones are well managed from a hygiene and utility perspective.

How can a bathroom occupancy sensor improve the hygiene of your building?

Office hygiene is a considerable challenge for businesses around the world – in the UK, businesses lose £13.7 billion annually due to the problem. 

Bathroom occupancy sensors give your facilities management team anonymous insight into washroom usage, allowing for cleaning staff to be deployed when a certain quota of visitors is reached. By receiving automatic notifications, your ablution facilities will be regularly attended to, and users can rest assured that their health and hygiene are prioritized. 

Effective management of washrooms reduces maintenance costs, ensuring that these facilities are sanitized when necessary and before issues become hazardous.  

Businesses and managers of public environments are increasingly conscious of the detrimental effects that poor washroom facilities could have on an organization's reputation.

Prospective employees or patrons will feel disinclined to accept a role or support a business that does not place importance on the hygiene and wellbeing of the occupants who frequent its premises. Deciding to proactively monitor usage levels can make a huge difference in how stakeholders perceive your organization.

To comply with privacy laws and avoid unwanted issues, ensure you are not using camera-based sensors in washroom spaces.

Benefits of occupancy IoT sensors

More and more businesses and organizations are growing increasingly conscious of the inefficiencies that their buildings may exhibit. With mounting concerns about energy consumption, hygiene, and occupants' user experience, incorporating occupancy IoT sensors into your facilities management systems can significantly improve the performance and utility of your buildings.

With the help of this real-time data, you can action the best and most effective processes to:

  • optimize your space in order to design practical workspaces that meet the needs of your employees. 
  • improve your energy efficiency profile by reducing wastage.
  • keep on top of hygiene and maintenance throughout your estate.
  • save money on energy by controlling the lighting and temperature in vacant spaces.
  • manage desk and meeting room usage that will enable better experience for your staff and help to improve their productivity by gaining visibility over conference room or workspace availability.

What is a vacancy sensor, and how is different from an occupancy sensor?

Occasionally, you may come across the term vacancy sensors. While, just like occupancy sensors, they aim to conserve energy, vacancy sensors need the occupant to manually turn a light on and will then turn it off once motion is no longer detected in a space. In contrast, occupancy sensors can automate the turning on and off of lights in response to someone entering or exiting a space. 

Vacancy sensors aren't a practical solution for all spaces. There are several reasons for this. Firstly, they increase physical contact with surfaces as the occupant has to touch the light switch. Secondly, if your building has enclosed spaces that aren't exposed to natural light, it may be difficult or even dangerous for occupants to enter these areas and have to locate the light switch. In such instances, it's better to have a sensor that will detect occupancy and automatically turn the lights on. 

The connection between occupancy sensors, occupancy analytics and smart buildings

Smart building technology is driven by the demand for more sustainable building management practices, energy efficiency goals, and the necessity to create dynamic, responsive, and optimized environments for occupants.

The electronic hardware you choose to install throughout your smart building needs to effectively integrate and feedback into your existing platforms so that you can experience the long-term benefits of making such an investment. True Occupancy sensors collect and store data in a cloud platform that allows different stakeholders to view and analyze this information remotely or whilst on-site. 

Ultimately, smart building technology will have a transformative effect on operations, enabling key stakeholders to monitor and assess essential data about how a building or space is being used. Increasingly, occupants, employees, and facilities management staff expect some aspects of a building's functionality to function automatically. 

As you embrace more of these smart building technologies into your standard operations, choosing solutions that can scale with your growing requirements is essential. True Occupancy offers seamless integration through pre-built connections and standard protocols to connect reliable occupancy data with desk and meeting room booking systems, cleaning scheduling tools, building management systems, and more.

How can you use occupancy detection sensor data to prove ROI?

The real value in installing occupancy detection sensors is the data you can collect and analyze to help you make more practical and ROI-based decisions. 

As traditional office environments transform to accommodate remote and hybrid workers, businesses will have to review their office layout and optimize or reduce space that is no longer required as a result of fewer employee numbers using the building.

Your decisions to renovate, improve, or enhance a space need to be fact-based. With the implementation of occupancy sensor technology, you can have access to data that:

  • Helps you understand exactly how occupants use your building.
  • Verifies underutilized spaces.
  • Captures the flow of occupants throughout a space. 

With the help of this data, you can action the best and most effective processes to manage usage, hygiene, maintenance, and energy consumption.

Occupancy sensor data can help you create optimal working conditions for your employees by providing insights into how they interact with the space you provide them. This will help your business remain flexible and easily adapt when new challenges arise.

View our case studies and resources here for more information on how we've helped our partners get results from their occupancy sensors.

How our occupancy sensors work

Our True Occupancy solution is one of the most comprehensive solutions on the market.

Our occupancy sensors connect to an intuitive dashboard that gives your property and facilities management teams immediate insight into a building's real-time utilization. From there, decision-makers can analyze the data, track performance against KPIs, and make adjustments at the most effective times. 

These sensors are non-intrusive, protect the privacy of occupants, and provide a cost-effective means of scaling your monitoring strategy as and when you need to.

Our sensors can be found globally in office spaces, restaurants, washrooms, meeting rooms, universities, and a host of other on-site facilities. We are trusted by many well-known organizations to assist with space planning, cost-saving initiatives, occupant wellbeing, and employee productivity strategies. To book a free demo and experience the benefits of True Occupancy for yourself, get in touch with us today.


Tom Bell

Product and Marketing Manager

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