#office climate

Getting people’s feedback

Some researchers have proposed asking officemates to basically vote on what the temperature should be. Using a phone app or website, building occupants say whether they’re too hot or too cold, and what would make them more comfortable. An algorithm then analyzes the groups’ answer and calculates a temperature estimated to be most acceptable to most people.

Some systems let users vote on whether they are comfortable, and what would make them more so. Carol Menassa, et al., CC BY-ND

However, that method has two significant limitations: To work best, it requires near-constant input from people who are supposed to be working – and still doesn’t factor in whether someone who is uncomfortable could help themselves by putting on or taking off a sweater. It also doesn’t take into account how people’s bodies experience temperature, which is closely tied to how cool or warm they prefer their environment to be.

Monitoring temperature remotely

In previous research, our group placed multiple temperature sensors around an office, and combined their data with information from wristbands that sensed occupants’ skin temperature and heart rates and apps that polled workers about how they felt. We found that adding the data about how people’s bodies were reacting made the algorithm more accurate at calculating the room temperature at which people occupying a given space would feel most comfortable.

A multi-sensor system monitors the environment and room occupants, and adjusts the room heat and cooling accordingly. Carol Menassa, et al., CC BY-ND

Our current project, seeks to make things even easier and less intrusive for people, eliminating the wristbands and apps, and only using remote sensing of people’s skin temperature to measure how comfortable they are. We developed a method using regular cameras, thermal imaging and distance sensors to detect occupants’ presence in a space, focus on their faces and measure their skin temperature. From that data, our algorithm calculates whether – and how – to change the temperature in the room regardless of the number of occupants in the space. When we tested it in an office occupied by seven people, they complained less about feeling uncomfortably cold or warm.

Face detection software coupled with temperature-sensing cameras can evaluate whether a person is warm, cold or just right. Carol Menassa, et al., CC BY-ND

This method is most effective in multi-occupancy spaces, like open-plan offices, meeting rooms and theaters. It can accommodate, and account for, differences in temperature between people in different areas of a room, whether they are standing or sitting or moving around. And it can adjust on the fly without requiring active human feedback. Our group will continue to explore this and other non-intrusive methods to help people feel more comfortable – and be healthier and more productive.

About The Authors:

Carol Menassa is Associate Professor of Civil and Environmental Engineering, at the University of Michigan; Da Li is a Ph.D. Student in Civil and Environmental Engineering at the University of Michigan, and Vineet Kamat is a Professor of Civil and Environmental Engineering, also at the University of Michigan