Humidity and Temperature Sensors: Essential Tools for Facilities Management

In the modern age of facilities management, maintaining optimal environmental conditions is essential for comfort, safety, and efficiency. That’s where humidity and temperature sensors have become a valuable tool for monitoring and controlling environmental conditions accordingly.

They provide facilities management with real-time data, enabling facility management to ensure proper ventilation and optimise energy usage. Integrated with IoT devices, these sensors let you make informed decisions, prevent damage to sensitive equipment, and reduce energy costs. If you want these management facilities integrated, you can consult a smart building solution provider.

In this blog, we’ll learn about various types of humidity and temperature sensors, their working and what factors you should consider while choosing them. We’ll also provide you with some of the recommended sensors sold by Forest Rock. So, let’s get started!

What are Humidity and Temperature Sensors?

Humidity and Temperature Sensors are essential tools used to monitor environmental conditions by measuring two key factors: humidity and temperature. These sensors are widely deployed in facilities management, as they help maintain optimal conditions for buildings and equipment. Here’s an overview of each sensor:

Humidity Sensors

Humidity sensors, also known as hygrometers, measure the amount of moisture in the air. This is typically expressed as relative humidity (RH), which is the ratio of the current amount of water vapour in the air to the maximum amount that the air can hold at a given temperature. There are different types of humidity sensors, including:

• Capacitive Sensors: Use a humidity-sensitive material between two conductive plates. As humidity levels change, the material’s dielectric constant changes, altering the capacitance.
• Resistive Sensors: Measure changes in electrical resistance as humidity levels change.
• Thermal Conductivity Sensors: Compare the thermal conductivity of dry air and humid air to calculate humidity.

Temperature Sensors

Temperature sensors measure heat in an environment and can be used to monitor, control, or regulate temperatures. They are used in various systems, such as heating, ventilation, and air conditioning (HVAC), manufacturing processes, and food storage. Common types of temperature sensors include:

• Thermistors: These sensors use materials whose resistance changes with temperature. They are highly sensitive and provide accurate readings.
• Thermocouples: These sensors generate a voltage based on the temperature difference between two different metal wires.
• Resistance Temperature Detectors (RTDs): These sensors change their resistance in response to temperature changes, usually made of platinum for high accuracy.

In facilities management, the combination of both sensors helps maintain the optimal environment. It ensures the comfort of occupants, protects equipment and adheres to safety regulations.

How do Humidity and Temperature Sensors Work?

Humidity and Temperature Sensors operate through different mechanisms depending on the type of sensor used. Here’s a breakdown of how each sensor works:

Working of Humidity Sensors (Hygrometers)

Humidity sensors measure the amount of moisture in the air and typically provide readings as relative humidity (RH). The three main types of humidity sensors are capacitive, resistive, and thermal conductivity. Here is how they function:

1. Capacitive Humidity Sensors

These sensors measure changes in capacitance, which is influenced by the moisture content of the air. When the air becomes more humid, the capacitance of the sensor increases.

Operation:

• Made of two metal plates with a non-conductive polymer layer between them.
• As the humidity level changes, the polymer absorbs or releases moisture, altering its electrical capacitance (the ability to store electrical charge).
• The sensor measures this change and converts it into a humidity reading. Capacitive sensors are widely used due to their accuracy and stability over a wide humidity range.

2. Resistive Humidity Sensors

Resistive sensors use materials that change their resistance based on changes in humidity. As the air becomes more humid, the resistance of the sensor decreases.

Operation:

• Use a hygroscopic (water-absorbing) material between two electrodes.
• As humidity levels change, the material’s resistance to electrical current changes as well. This variation in resistance is measured and converted into humidity levels.
• These sensors are common in industrial applications due to their simplicity.

3. Thermal Conductivity Humidity Sensors

These sensors measure changes in thermal conductivity, which is influenced by the moisture content of the air. When the air becomes more humid, the thermal conductivity of the sensor decreases.

Operation:

• It compares the thermal conductivity of dry air versus humid air. Since water vapour has different thermal properties than dry air, the sensor detects changes in the heat transfer rate.
• These are used in environments with extreme temperature or humidity conditions.

Working of Temperature Sensors

Temperature sensors detect heat by monitoring changes in the physical properties of certain materials. There are various types of temperature sensors, with the most common being thermistors, RTDs (Resistance Temperature Detectors), and thermocouples:

1. Thermistors

Thermistors are similar to RTDs but often have a more significant change in resistance with temperature.

Operation:

• Made of ceramic or polymer materials that change resistance based on temperature.
• In a Negative Temperature Coefficient (NTC) thermistor, resistance decreases as the temperature increases, while in a Positive Temperature Coefficient (PTC) thermistor, resistance increases with temperature.
• Thermistors are highly sensitive and are ideal for precise temperature measurements.

2. Thermocouples

These sensors generate a voltage based on the temperature difference between two dissimilar metals. The voltage output is directly proportional to the temperature difference.

Operation:

• Composed of two different metals joined at one end. When heated, they generate a small voltage based on the temperature difference between the metals.
• Thermocouples are robust and can measure a wide range of temperatures, making them suitable for industrial and high-temperature environments.

3. RTDs (Resistance Temperature Detectors)

RTDs change their resistance based on changes in temperature. As the temperature increases, the resistance of the RTD also increases.

Operation:

• Made from pure metals like platinum, which have a predictable resistance change with temperature.
• As the temperature increases, the resistance in the metal also increases. This change is measured and converted into temperature readings.
• RTDs offer highly accurate temperature readings and are used in industrial and scientific applications.

How do They Work Together?

In facilities management, combined sensors are often used, integrating both humidity and temperature measurements in one device. These sensors often use microchips to process the signals and provide digital or analogue outputs. That makes it easy to monitor both parameters simultaneously. Here is how they work:

• These sensors work by continuously measuring both the ambient humidity and temperature.
• The data is processed, often by a microcontroller or a dedicated sensor module, and can be transmitted to building management systems (BMS) for monitoring, controlling HVAC systems, or triggering alerts when environmental thresholds are breached.

Benefits of Installing Humidity and Temperature Sensors

Installing Humidity and Temperature Sensors in facilities management offers numerous benefits, helping you keep environments optimised, maintain safety, and improve efficiency. Here are the key advantages:

• Precise Control: Humidity and temperature sensors ensure that indoor environments are kept within the ideal range for specific operations. This is crucial in settings such as data centres, hospitals, manufacturing facilities, and offices.
• Protect Equipment: Sensitive equipment, like servers and electronics, can be damaged by high humidity or extreme temperatures. Sensors help prevent this by enabling automatic climate control adjustments.
• Ensure Product Quality: In industries like pharmaceuticals and food storage, maintaining proper humidity and temperature is essential for preserving product integrity, preventing spoilage, and extending shelf life.
• Optimised HVAC Systems: By monitoring environmental conditions, sensors help adjust heating, cooling, and ventilation (HVAC) systems dynamically. That minimises energy waste by only using energy when necessary, resulting in lower utility costs.
• Prevent Overcooling and Overheating: Continuous monitoring prevents the overuse of air conditioning or heating systems, ensuring that only the required amount of energy is used to maintain comfortable conditions.
• Automated System Adjustments: Integration with traditional and IoT-based building management systems (BMS), allowing real-time adjustments based on sensor data, further optimising energy use and reducing the carbon footprint.
• Reduce Maintenance Costs: Monitoring humidity and temperature in real-time helps to manage and maintain equipment. That prevents breakdowns caused by extreme environmental conditions.
• Early Warning Systems: Many humidity and temperature sensors can be programmed to trigger alerts when environmental conditions approach critical levels. That allows facility managers to take action before damage occurs.

By installing humidity and temperature sensors, facility managers can significantly improve the management of environmental conditions. It enhances energy efficiency and overall system performance while also safeguarding equipment and maintaining occupant comfort.

Applications of Humidity and Temperature Sensors in Facilities Management

Humidity and temperature sensors play a vital role in facilities management, ensuring optimal conditions for various processes and activities. Here are some key applications:

HVAC Systems

Humidity and temperature sensors are key tools for managing energy use in buildings. By working together, these sensors help us understand the heat content of the air, known as “enthalpy”. Here’s how they can be used to save energy:

1. Monitor Conditions:
Place sensors around the building to keep track of temperature and humidity levels in real-time.

2. Understand Air Quality:
The data from these sensors helps us understand the amount of moisture in the air. This is important because both temperature and humidity affect how comfortable we feel and how much energy we need to heat or cool the space.

3. Adjust HVAC Systems:
With this information, we can make smart adjustments to the heating, ventilation and air conditioning (HVAC) systems.

4. Optimise Energy Use:
By continuously monitoring and adjusting based on the sensor data, we can maintain a comfortable indoor environment while using less energy. This not only cuts down on energy bills but also supports sustainability efforts.

This approach helps facilities run more efficiently and comfortably, all while being kinder to the environment.

This leads to improved energy efficiency, reduced energy consumption, and enhanced indoor air quality. By monitoring humidity levels, HVAC systems can help prevent mould and mildew growth, ensuring a healthier and more comfortable environment for occupants.

Building Automation Systems

Integrated with Building Automation Systems, humidity and temperature sensors allow remote monitoring and automated adjustments of environmental controls. That optimises energy use and maintains indoor air quality.

Modern sensors often communicate with Internet of Things (IoT) devices, allowing for real-time data collection and control over multiple environmental factors like lighting, security, and ventilation.

Indoor Air Quality (IAQ) Management

Indoor air quality is a critical concern for building occupants. Humidity and temperature sensors play a vital role in maintaining healthy IAQ. High humidity levels can contribute to mould growth, which can have serious health consequences. By monitoring humidity levels, facilities managers can identify and address potential mould issues quickly.

Plus, maintaining a comfortable indoor temperature and humidity level can improve occupant well-being and productivity. Sensors can also help ensure compliance with various IAQ regulations and standards.

Data Centre Management

In traditionally designed centres, where sensitive electronic equipment is kept, maintaining optimal humidity and temperature levels is crucial. Excessive humidity can damage equipment and lead to costly downtime.

Maintaining optimal temperature and humidity levels is indeed crucial for reducing the Power Usage Effectiveness (PUE) of a modern data centre, especially those built to the ASHRAE standards. Here’s how these factors play a role:

Temperature and Humidity Control

• Temperature Management:
  • Adiabatic Cooling: This method uses the evaporation of water to cool the air, which is highly energy-efficient compared to traditional mechanical cooling. By maintaining the correct temperature, adiabatic cooling helps reduce the energy required for cooling systems, thereby lowering the PUE.
  • Heat Recovery: In data centres like BladeRoom and Arc, the heat generated by servers is recovered and reused to maintain optimal temperatures. This reduces the need for additional heating, further improving energy efficiency.
• Humidity Control:
  • Optimal Humidity Levels: Maintaining the right humidity levels prevents static electricity buildup and condensation, both of which can damage sensitive electronic equipment. Proper humidity control ensures the longevity and reliability of the equipment, reducing the risk of downtime and associated costs.
    

Impact on PUE

• Energy Efficiency: By using adiabatic cooling and heat recovery, data centres can significantly reduce the energy required for cooling. This directly impacts the PUE, which is a measure of how efficiently a data centre uses energy; specifically, the ratio of total building energy usage to the energy used by IT equipment.
  
• ASHRAE Standards: The ASHRAE 90.4 standard provides guidelines for energy efficiency in data centres, including recommendations for temperature and humidity ranges. Adhering to these standards helps data centres optimise their environmental controls, leading to lower PUE values.
  

Examples: BladeRoom and Arc Data Centers

• BladeRoom: Utilises modular data centre designs with advanced cooling techniques, including adiabatic cooling and heat recovery, to maintain optimal conditions and achieve low PUE.
• Arc Data Centers: Implements similar strategies, focusing on energy-efficient cooling and precise environmental control to enhance performance and reduce operational costs.

By integrating these advanced cooling and environmental control techniques, using temperature and humidity sensors, modern data centres can achieve significant energy savings and maintain high operational efficiency, ultimately reducing their PUE and environmental impact.

Healthcare Facilities

In healthcare facilities, maintaining the right temperature and humidity is crucial for patient recovery and overall comfort. Here’s how humidity and temperature sensors can aid in patient recovery:

1. Comfort and Healing:
Proper temperature and humidity levels help create a comfortable environment, which is essential for patient recovery. A comfortable environment can reduce stress and promote better sleep, both of which are important for healing.

2. Infection Control:
High humidity levels can promote the growth of mould, bacteria, and dust mites, which can lead to infections. By monitoring and controlling humidity, healthcare facilities can reduce the risk of infections, especially in vulnerable patients.

3. Respiratory Health:
Patients with respiratory conditions, such as asthma or COPD, can be particularly sensitive to changes in humidity and temperature. Maintaining optimal levels can help prevent exacerbations of these conditions and improve overall respiratory health.

4. Medication and Equipment Storage:
Certain medications and medical equipment require specific temperature and humidity conditions to remain effective. Sensors ensure that these conditions are maintained, preventing degradation and ensuring that patients receive the best possible care.

5. Real-Time Adjustments:
Sensors provide real-time data that can be used to make immediate adjustments to HVAC systems. This ensures that any fluctuations in temperature or humidity are quickly corrected, maintaining a stable environment for patients.

By using humidity and temperature sensors, healthcare facilities can create a safer, more comfortable environment that supports patient recovery and well-being.

Food Processing and Storage

The food industry relies heavily on humidity and temperature sensors to maintain product quality and safety. By accurately monitoring and controlling these environmental factors, facilities can prevent food spoilage.

1. Cold Storage Facilities:
In cold storage warehouses, maintaining the right temperature and humidity is crucial to prevent food spoilage. Sensors continuously monitor these conditions to ensure they stay within the optimal range. If the temperature rises or humidity levels become too high, the sensors trigger alerts, allowing for immediate corrective actions to prevent bacterial growth and spoilage.

2. Baking Processes:
During baking, precise control of humidity and temperature is essential to achieve the desired texture and quality of baked goods. Sensors help maintain the right conditions throughout the baking process. For instance, too much humidity can make baked goods soggy, while too little can cause them to dry out. By monitoring and adjusting these factors, sensors ensure consistent product quality.

These examples highlight how critical humidity and temperature sensors are in maintaining food safety and quality throughout the production and storage processes.

How to Choose the Right Humidity and Temperature Sensors?

Selecting the right humidity and temperature sensors for your specific application requires careful consideration of several factors. Below are the key factors to consider when choosing humidity and temperature sensors:

Accuracy and Precision

The accuracy of humidity sensors is critical, especially in environments like healthcare, manufacturing, or data centres where even slight deviations can affect operations. Sensors typically offer accuracy ranges between ±1% and ±5% for relative humidity.

Check the sensor’s accuracy rating, which indicates the maximum deviation from the actual value. Precision refers to the sensor’s ability to consistently provide the same reading under the same conditions. Choose sensors with high accuracy and precision to avoid discrepancies.

Measurement Range

Different environments require sensors with varying measurement ranges. For example, cold storage facilities may need sensors that operate in sub-zero temperatures. Conversely, greenhouses require sensors that can measure high humidity and temperature levels.

Evaluate the sensor’s measurement range to ensure it can monitor the environmental conditions in your specific facility. Choose a sensor that covers both the minimum and maximum expected temperature and humidity levels.

Response Time

In environments where conditions can change rapidly, such as data centre manufacturing settings, a sensor’s response time is crucial. A faster response time allows facility managers to take immediate action, minimising potential damage.

Choose sensors with a fast response time, especially in areas where quick fluctuations in temperature or humidity occur. If you get a quicker response, that could lead to saving equipment failure, product spoilage, or compromised safety.

Environmental Durability

Humidity and temperature sensors must be durable enough to withstand the specific conditions of the environment. For instance, sensors in industrial settings may be exposed to dust, chemicals, or extreme temperatures, while sensors in outdoor facilities must withstand weather changes.

Consider checking the Ingress Protection (IP) rating, which indicates resistance to solid particles and liquids. Robust sensors will last longer and maintain accuracy in challenging environments.

Connectivity and Integration

The ability of the sensors to connect and integrate with existing building management systems (BMS), HVAC controls, or IoT platforms is valuable for real-time monitoring and automation.

Opt for sensors that support modern wireless technologies such as WiFi, Zigbee, or Bluetooth. That will enable wireless integration with your other systems. Compatibility with smart building systems allows for remote monitoring and centralised control of multiple sensors across various locations.

Cost and Budget

While higher-end sensors offer more features and greater accuracy, they come at a premium. It’s essential to balance the cost with the accuracy and reliability you need. Evaluate the total cost of ownership, including the initial purchase price, installation, maintenance, and calibration costs.

Sometimes, investing in more expensive high-performance sensors with long lifespans can result in savings in the long run by reducing energy costs and minimising maintenance requirements.

By considering these factors, you can choose humidity and temperature sensors that align with the specific needs of your facility. It will help you ensure reliable operation, energy efficiency, and better environmental control.

Recommended Humidity and Temperature Sensors

Delta O3 Edge Standalone Sensor Array

This sensor integrates temperature, humidity, light, and motion detection. It also supports audio feedback and can communicate via BACnet and MQTT protocols, making it versatile for smart building applications.

Key Features:

• Integrated temperature, humidity, light, and motion sensors
• Configurable LED ring and audio tone feedback
• Supports BACnet and MQTT protocols
• Bluetooth BLE5.0 for custom app development
• Dual Ethernet ports for daisy-chaining with power failure tolerance

Elsys ELT-2 Outdoor LoRaWAN® Wireless Sensor

Designed for harsh outdoor environments, this sensor can monitor temperature, humidity, and a variety of external sensors. That makes it suitable for industrial IoT applications using LoRaWAN.

Key Features:

• Outdoor-rated with a rugged design
• Supports temperature and humidity monitoring
• LoRaWAN communication for long-range transmission
• Works with external sensors for enhanced monitoring
• Low power consumption for long-term use

Elsys ERS Eye Indoor Environment Sensor

Ideal for indoor spaces, this sensor tracks temperature, humidity, and motion. It is perfect for energy-saving solutions and optimising indoor air quality with LoRaWAN communication.

Key Features:

• Tracks indoor temperature, humidity, and motion
• LoRaWAN communication for easy integration
• Energy-efficient design
• Detects room occupancy and light levels
• Small and discreet for indoor environments

ALTA Industrial Wireless High Temperature Sensor

This industrial-grade sensor is built to withstand high-temperature environments. It wirelessly transmits temperature data, which is ideal for industrial monitoring with extended range and reliability.

Key Features:

• Monitors high temperatures in industrial settings
• Wireless transmission of data over long distances
• Industrial-grade durability for harsh environments
• Long battery life for reliable monitoring
• Extended wireless range for flexibility

ALTA Wireless Humidity Sensor (AA)

A wireless humidity sensor that offers accurate and real-time monitoring of relative humidity. It features a long battery life and wireless range, making it suitable for building automation or environmental monitoring applications.

Key Features:

• Measures relative humidity with high accuracy
• Wireless with extended transmission range
• Long battery life, powered by AA batteries
• Ideal for building automation and environmental monitoring
• Configurable for various industrial and commercial applications

O3 HUB2

A multi-functional sensor hub with capabilities like temperature and humidity monitoring, PIR motion detection, and light sensing. It features audio and visual user feedback with customisable settings and supports integration with both BACnet and MQTT.

Key Features:

• Monitors temperature, humidity, motion, and light
• Customisable LED and audio feedback
• Supports BACnet and MQTT for easy integration
• Bluetooth BLE5.0 for app customisation
• Dual Ethernet for flexible network setup

These were some of the humidity and temperature sensors we recommended. If you would like to explore more such products for smart buildings, explore our IoT shop.

Final Thoughts

Humidity and temperature sensors are vital components in modern facilities management. They ensure that buildings maintain optimal environmental conditions for both people and equipment. By providing accurate, real-time data, these sensors enable smarter decisions around climate control and energy efficiency.

These sensors have a range of real-world applications, from commercial buildings to data centres. With the integration of IoT devices, these sensors allow facilities to make better decisions regarding environmental control. You can choose any of the humidity and temperature sensors based on your preferences and requirements.

If you need such integrations made into your building management system, contact our experts today. With their experience in IoT devices and various integrations, they can help you streamline facilities management.