Cleanrooms are engineered spaces with relatively low levels of environmental pollutants, including dust, bacterial microbes, aerosol particles, vapors, and other contaminants. Cleanrooms are specifically used for equipment or process research, development, and manufacturing in the electronic, pharmaceuticals, aerospace, automotive, information technology industries, and more.
The demand for cleanrooms has increased as multiple industries emphasize quality inspections and controls, strict enforcement for defects, and restrictive manufacturing practices. Therefore, designing or setting up a cleanroom requires particular consideration for parameters such as temperature and humidity.
The Ideal Temperature & Humidity Levels in Cleanrooms
It is essential that cleanrooms must constantly maintain certain temperature standards. Otherwise, workers will sweat or shiver, causing more particle release, which can lead to contamination and jeopardize the quality of any production.
The ideal temperature varies depending on the products and equipment being manufactured. The optimum temperature for a standard cleanroom is 70°F (21°C) with a 2-degree variance either way. For aerospace cleanrooms, the best air temperature ranges from 67°F to 77°F (roughly 19°C to 25°C).
Like temperature control, the humidity in a cleanroom must also remain stable. Incorrect humidity levels can cause discomfort to the whole cleanroom area, especially for those working on it. This results in errors, low-quality products, and production delays. The ideal relative humidity (RH) range in standard cleanrooms is 30-40%. For aerospace, the best cleanroom humidity level is usually 40%-60%.
The Importance & Effects of Humidity Control in Cleanrooms
Humidity level control in cleanrooms is critical for meeting government and company requirements and for ensuring the quality of processes and products. Humidity levels beyond the ideal RH can cause microbial growth, evaporated solvents, corrosion, product spoilage, and water absorption. On the other hand, low humidity levels cause cracking, static buildup, and electrostatic discharge.
Here are some examples of the effects of high humidity in semiconductor and pharmaceutical cleanrooms:
Hygroscopic polymers — known as photoresists — used in microcircuits and microchips absorb moisture, resulting in the cutting or bridging of circuit lines. This often leads to circuit failures. Moreover, various problems can arise when the humidity level in a wafer fabrication area fluctuates. Issues include increased bake-out times and rapid evaporation of solvents resulting in condensing moisture from the air. This extra water can alter the developer properties and be absorbed by the semiconductor materials.
In high humidity, fine powders absorb moisture and clog the powder feed to the tableting press. This powder inconsistency results in crumbling tablets, which are unsuitable for use. Humidity fluctuations also mean complex modifications to bed temperature and spraying rates, causing heat damage and moisture intrusion. Lastly, humidity in air ductwork creates moist environments for bacterial colonies to grow, resulting in process contamination.
Using an Air Conditioning System To Control Humidity
Because relative humidity decreases as temperature drops, lowering the temperature in the cleanroom will reduce humidity. When dehumidifying a space with air conditioning, the system lowers the coil temperature below the dew point of the cleanroom space. As a result, water vapor condenses on the coil and dehumidifies the space. The air must then be reheated and pumped back into the cleanroom to keep the ideal room temperature.
Quality Cleanroom Environment Control Solutions From Air Innovations
Air Innovations specializes in designing and developing packaged cooling systems (self-contained and remote) to achieve precise temperature, humidity, and filtration control. Our humidity control systems can regulate humidity to ±0.5% RH from desiccant levels to 95% saturation. We work with various industries, including aerospace, semiconductors, cleanrooms, pharmaceuticals, military, oil and mining, and many others.
Our products include the following configurations:
AdvancAir® – Custom Cleanroom Air Conditioner
AdvancAir® custom environmental control units for cleanrooms provide increased capacity and improved performance while taking up less space. These systems are custom-built to your specifications and come in various configuration options. AdvancAir units can be used in semiconductors, microelectronics, aerospace, compact disc production, ultra-clean assembly, and metrology.
HEPAir® – Cleanroom HVAC Units
HEPAir® cleanroom HVAC units, which come in horizontal modules, are the ideal solution for maintaining a consistent temperature, humidity, pressure, and sanitation. They are used in cleanrooms and other industrial and commercial applications, such as compounding pharmacies, hospitals, facility additions, laboratories, mini-environments, and process isolators.
Contact Our Experts for All Your Temperature & Humidity Control Needs
Air Innovations has a dedicated division for designing and manufacturing unitary and custom HVAC systems for cleanrooms and critical environments. We also have a fully integrated modular environmental system specifically for the cleanroom industry. And, like all Air Innovations ecological control systems, we can customize our cleanroom air conditioning systems in terms of size, features, and functionality.