If you work in an office or know someone who does, you have probably already heard that the patriarchy has set the thermostat too low. A recent study by two Dutch researchers seemingly provided proof of this institutional sexism and promptly set off an Internet firestorm. The study claims that the model that ties thermal comfort to the air temperature used for the control of air conditioning systems relies only on data from men. Moreover, because the metabolic rate of males and females are different, the approach provides too much cooling for female occupants, leaving them to suffer in frigid conditions while their male counterparts are comfortable. The study is unfortunately wrong on two counts: air temperature settings are based on data from equal amounts of men and women, and both men and women suffer from temperatures that are too cold.
If You Can’t Measure It, You Can’t Manage It
Controls for air conditioning need to be set to something that can be measured. Thus, air temperature, which can be measured and is highly correlated to thermal comfort, is used to manage the operation of air conditioning equipment. The specific temperatures engineers use for systems are set by the American Society of Heating, Refrigerating, and Air-Conditioning Engineer’s (ASHRAE’s) Standard 55, Thermal Environmental Conditions for Human Occupancy. In a press release, ASHRAE reiterated the fact that Standard 55 is based on the preferred temperature of more than 1,000 subjects with an equal amount of men and women. Unlike paychecks, Standard 55 does not have a gender bias.
The problem highlighted by response to the Dutch study is that temperature and comfort are related but not identical. How comfortable a person feels in a building depends on how much cooling they need (what they are doing, what they are wearing, how old they are, and their body fat) and the state of the air that is provided (temperature, humidity, volume, and speed). Controlling a system that depends on a dozen variables by a single variable leads to both women and men being uncomfortable. Saying that the average person is comfortable at a certain temperature is akin to describing a person with a chicken and a person without a chicken as two people who have an average of half a chicken.
Utopia with the Dialogue of Comfort
Wouldn’t it be great if air conditioning was controlled by comfort rather than temperature? Historically, this dream has been technologically unfeasible. To truly measure comfort, the feelings of building occupants need to be gathered. Not only are engineers bad with feelings, but there isn’t a sensor that can measure them. Nonetheless, air conditioning systems are moving toward comfort-based control.
The Leadership in Energy & Environmental Design (LEED) building certification program, which rates buildings based on their indoor environment and ecological impact, credits building operators for assessing how comfortably occupants actually are through a survey. Building Robotics, an Oakland-based startup, closes the comfort control loop with its Comfy software. Rather than relying on exclusively on sensors, Comfy has occupants provide direct feedback via a web or smartphone app and changes temperature and airflow accordingly. As better technology enables better building controls, women and men alike will be able to find comfort in the built environment.
Tags: & Air Conditioning, ASHRAE, Building Innovations, Intelligent Building Management, LEED
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