Thermal Comfort: Temperature and Humidity Control in Buildings

Optimizing occupant comfort isn’t just a matter of preventing complaints. Building occupants feel healthier and perform better in environments that offer sufficient thermal comfort. Temperature, humidity, and ventilation have been found to profoundly impact productivity and cognition, and improving thermal comfort is one of the most affordable employee-related investments companies can make. That’s why controlling thermal comfort within office buildings and other structures in which people work is a top priority for savvy businesses.

Customizing Climate: Thermal Comfort, Temperature and Humidity

In indoor environments, thermal comfort is affected by: 

• Air circulation
• Air temperature
• Relative humidity 

In smart buildings, Internet of Things (IoT) devices continuously measure these variables while intelligent building management platforms evaluate conditions and make adjustments to keep conditions within particular parameters. 

Air and Ambient Temperatures

Indoor air temperature results from the temperature immediately surrounding a person’s body, while ambient temperature stems from a heat source within the environment, such as the sun shining through a window, machinery in operation, or heating elements. Both these temperature measurements help determine thermal comfort. 

IoT temperature sensors fall into these four general categories: 

• Negative temperature coefficient thermistors work well in extreme environments where temperatures can drop rapidly, as they provide considerable resistance at lower temperatures, reflecting falling temperature accurately and quickly
• Resistance temperature detectors offer the most accurate measurements, using a wire or film wrapped around a glass or ceramic core to measure how much resistance occurs between the element
• Semiconductor-based sensors incorporated into integrated circuits record temperature changes by using temperature-sensitive voltage to compare current conditions
• Thermocouples consist of two wires made from different metals, which are placed at various points so that they are able to detect temperature changes through associated changes in voltage. 

HVAC controls can be automated to respond to sensor data to ensure comfort.

Humidity

Relative humidity is a ratio of the maximum amount of water vapor air can contain at current temperatures and the actual amount of water in the air. When relative humidity falls between 40-70%, thermal comfort isn’t significantly affected. However, when HVAC units aren’t operating optimally, humidity levels can rise to uncomfortable levels. Temperature and humidity are invariably linked, as higher relative humidity levels make temperatures seem warmer while lower levels of humidity make them seem cooler.

Commonly used humidity sensors include: 

• Capacitive sensors use a porous insulating substance at their center with two electrodes to monitor water vapor in the air, measuring humidity levels as a change in voltage occur when vapor reaches the electrodes
• Resistive sensors operate similarly to capacitive sensors, though they are less sensitive, using ions in salts to measure relative humidity via changes in resistance on their electrodes
• Thermal sensors are paired to conduct electricity between them that measure their differences to determine humidity levels in the air, with dry nitrogen coating one to measure air temperature and the other measuring ambient air 

These sensors are particularly important in hot, humid environments. High humidity levels affect how the body deals with heat, as when humidity reaches levels of 80 percent or more, less sweat evaporates from the body. It is this evaporation of sweat that reduces body temperature, so when humidity levels are too high, heat-related conditions such as heat stroke or heat exhaustion are more likely to occur. 

Air Circulation

The movement of air makes air temperatures seem cooler, The faster air moves, the faster a body loses heat. In simple terms, this is why fans help keep people cool even without temperature changes. Additionally, indoor environments with still or stagnant air that’s been heated artificially may cause stuffiness that increases discomfort. Smart building management platforms use IoT data to manage air circulation and filtration, while other sensors that analyze traffic and occupancy ensure enough fresh air reaches an area to deal with the number of occupants present.

Integrating IoT Devices for Thermal Comfort, Temperature and Humidity 

An intelligent building management platform, like onPoint, utilizes machine learning algorithms to optimize thermal comfort. With onPoint, HVAC and other building equipment doesn’t just respond to an arbitrary schedule or even to real-time information; it can respond based on both actual and anticipated conditions to keep occupants as comfortable as possible at all times. It can even be used to customize conditions by room, floor, or zone so each area suits the exact needs of occupants. onPoint also allows you to implement predictive maintenance to prevent malfunctions and downtime from affecting comfort.

A master systems integrator will help you make the most of smart technologies for thermal comfort, temperature, and humidity control. Not only will they ensure sensors are placed correctly, they will also ensure building systems work together optimally. With their guidance, your building will become a better, safer, and more productive place to work. 

Buildings IOT offers the state-of-the-art services and products you need for outstanding thermal comfort, temperature, and humidity control. Contact our team of experts to learn more about what we can do for you.