Clean Room FAQs: Questions to Ask Before Designing Your Industrial Clean Room

Welding, cutting, coating, or even prototyping and R&D — short-term industrial projects require clean air to ensure employee safety and production efficiency. Retractable clean rooms, custom-configured with multi-layered industrial air filtration, are built to create clean air environments wherever they are needed, which allows operations to balance long-term work in the facility with short-term projects. Modular clean rooms are an optimum efficiency solution.

Given the many design and operating regulations, specifying an industrial clean room can seem complicated, but it doesn’t have to be.

You can get started by addressing these four primary criteria:

1. How will the clean room be used? The process taking place inside a clean room will determine its design and construction materials.
2. Are there any humidity and temperature requirements?
3. Do you need a positive pressure clean room to keep contaminants out of the manufacturing space or a negative pressure clean room to keep the contaminants from escaping into the surrounding space?
4. What space is required to accommodate your activity? Air Changes per Hour (ACH) is a key aspect of clean air filtration, and it is calculated based upon the cubic feet of the clean room space (height, width and length).

First, focus on these key questions that will provide the information needed to design the most effective industrial clean room.

What is the Work Being Done in the Clean Room?

How the clean room will be used establishes whether you need a positive pressure clean room or a negative pressure clean room. A positive pressure clean room provides clean air to the people and the process inside the unit while protecting them from outside contaminants. If you must provide clean air inside the unit and keep the contaminants from escaping into the surrounding space, you will need a negative pressure clean room.

You also must know if the work process generates any particulate or gases that need to be removed from the enclosure and captured within a filtration chamber.

The number of personnel, their frequency of access, and necessary application equipment also are among the factors that could influence clean room design.

Is Clean Room Classification Required?

Industrial clean rooms often are used even if they are not required for a specific process or application. Clean rooms keep employees safe, equipment clean, and productivity at a high level.

But if a clean room is a requirement for the task, do you know what level of clean room you require? Clean room classification design is based on the amount of HEPA filtration and the number of air changes per hour (ACH), which is how often it passes through the filter system. A class 100,000 clean-room allows 100,000 particles at 0.5 micron within a cubic meter. A class 10,000 allows only 10,000 particles at 0.5 micron within a cubic meter and is therefore double the filtration and double air changes per hour.

For contrast, the ambient outdoor air in a typical urban area contains 35,000,000 particles for each cubic meter in the size range 0.5 μm and bigger.

In order to reach an ISO goal, a manufacturer must factor in the size of the room, the number of filters, and the frequency of the ACH. They also need to determine how many cubic feet of air must be filtered per minute to limit the number of particles to 10,000 or 100,000 per cubic foot in that size room? How often must filters be changed?

What Space Do You Need for the Clean Room? How Much is Available?

Working space can be a significantly limiting factor when designing your clean room. Available ceiling height, for example, will influence ventilation, air conditioning costs, and the ease of replacing air filters.

Additionally, some operations require gowning before workers enter the clean room; space constraints may dictate either an internal or external gowning room. An air shower may even be needed, depending on how clean the environment needs to be.

The size of the clean room will impact the ACH required to meet your air cleanliness goal. The lower the ISO class, the more often you will need to pass the air through the filter. A conventional office building or home system usually makes two to four air changes per hour, but a clean room can range from 10 to 250 or more depending upon the requirements.

Will Heat Load Be Consistent Through Operations?

Many factors impact the temperature in a building, let alone an enclosure. What will impact the heat load inside the clean room? For example, ovens, lighting, transformers, and computer servers emit heat.

Heat load for small equipment such as laptops can be considered negligible, but if there are 40 laptops, then it probably needs to be accounted for. Servers, however, generate larger heat loads that will have an impact.

Is the heat load consistent over a working 8-hour shift or 24-hour period? If the heat load is not constant and is process based (i.e. welding or brazing), what is a typical shift schedule including setup/working/tear down/reset time?

Other design-related considerations include:

• Does the ambient air need to be amended to ensure your clean room meets your process specs?
• Will the enclosure be within direct sunlight?
• Is the system required to provide humidification as well as de-humidification?
• Is the system required to provide heating as well as cooling?
• What power is available on site?

Learn More About Industrial Clean Rooms

Duroair modular clean rooms can be placed anywhere in a manufacturing facility without having to install supplementary ductwork — or pay for ongoing air make-up costs. Our portable, retractable enclosures with non-vented air filtration can be custom-engineered for large or small self-contained work environments to help guarantee worker safety from toxic dust and fumes, while reducing operating expenses and increasing productivity.