Aerospace & Defense cleanroom classifications regulate a cleanroom’s degree of cleanliness and are defined by the allowed amount of contamination by particle count and size, as well as the necessary air change rates depending on the cleanroom’s classification level. Aerospace and defense cleanrooms are typically regulated by the classification standards of two major organizations: The International Standards Organization (ISO) and the American Society for Testing and Materials (ASTM).

ISO Cleanroom Classifications for Aerospace and Defense Cleanrooms

The International Standards Organization developed the set of standards by which all cleanroom industries and applications must follow. ISO 14644-1 outlines the requirements for all cleanroom environments.

ISO 14644-1

ISO 14644-1 describes cleanroom cleanliness levels in terms of Classes 1-9, where Class 9 is equivalent to the cleanliness of room air and Class 1 represents the cleanest possible cleanroom environment. As the classification number falls, cleanrooms must comply with stricter standards to reach a cleaner, more controlled environment. The majority of aerospace and defense cleanrooms fall within ISO Classes 7-8, although some sensitive applications, such as the development of microchips or sensors may be governed by stricter classifications.

Understanding ISO Aerospace Cleanroom Classifications

ISO 14644-1 outlines cleanliness standards for aerospace and defense cleanrooms by determining the allowed contamination levels in each ISO class in terms of air particle size and count, air change rates or airflow velocity, and percentage of ceiling coverage for filtration. 

• Particle Count: Particle count refers to the number of particles of a certain size per cubic meter. Stricter ISO classes allow fewer particles, and also restrict the size of those particles. 
• Air Change Rate: The air change rate at is how quickly air is removed, filtered, and replaced within your cleanroom. 
• Ceiling Coverage: Ceiling coverage refers to the percentage of ceiling coverage for HEPA filter/fan units, or FFUs. 

Understanding the way these elements affect the cleanliness of your facility is the key to designing a successful cleanroom.

ASTM Standards for Aerospace & Defense Cleanrooms

American Society for Testing and Materials (ASTM) has also developed a set of International Standards, which test the cleanroom’s ability to limit contamination through the restriction of allowed particles in the cleanroom environment. They also deal with the more technical aspects of aerospace and defense applications, including the cleanroom’s ability to control mechanical, thermal, chemical, and electrical properties within the controlled environment.

Aerospace cleanrooms must comply with ASTM relevant to their application and use of materials. This could include regulation for the handling and disposal of combustible fuels, static control systems, and even processes for parts manufacturing. More extreme standards apply for highly sensitive applications, where airborne particle concentrations must be strictly controlled such as in the development of spacecraft hardware, fine electronics, or optical devices.

Blending Aerospace Cleanroom Classification Standards

Some aerospace and defense cleanrooms must be able to comply with different classifications for the different tasks or projects, or different stages within the same project, such as from manufacturing to assembly to packaging. 

Aerospace and defense cleanrooms need to be able to adapt to the circumstances of your work, and have everything necessary to evolve with project requirements and keep products and workers safe. This includes highly specific control over environmental factors and filtration needs, monitoring equipment to maintain strict particle count and temperature ranges, and proper solutions for supporting or storing equipment to effectively utilize the facility’s space.

Aerospace and Defense Cleanroom Design

Aerospace and defense cleanrooms require active filtration and complete control over temperature and humidity, as well as other environmental factors. The cleanroom design should address the three main areas of concern to reach strict aerospace cleanroom classifications:

• Particle count: Aerospace cleanroom design should include a special airflow pattern that makes use of filters in the most efficient and effective way possible to trap and remove particles, and replace the air in the room with air that is fresh and contaminant-free.
• Air change rate: While less stringent aerospace and defense applications may only require an air change rate of 5-48, defense cleanrooms with strict air quality standards may require hundreds of air changes per hour. In these cases, it’s expressed as air velocity, because air is constantly moving as it’s filtered out and replaced.
• Ceiling coverage: The more stringent your aerospace cleanroom classifications, the higher percentage of ceiling coverage required to filter air properly. Ceiling fan coverage is closely related to air change rate, as more FFUs are necessary to complete more air changes.

Modular Cleanroom Design for Aerospace and Defense Cleanrooms

Modular cleanrooms are ideal for the aerospace and defense industries — particularly applications with changing requirements as they can meet the needs of customized spaces, including those with oversized equipment and products. The two main types of cleanrooms used for aerospace and defense applications are HardWall cleanrooms and RigidWall cleanrooms.

• HardWall cleanrooms are the most common type of cleanroom used in aerospace and defense applications, as they offer a high level of control over environmental factors, so they can easily reach with the strictest aerospace cleanroom classifications. 
• RigidWall cleanrooms can also provide a suitable environment for aerospace and defense applications and can reach a variety of aerospace cleanroom classifications. They consist of clear panels that can easily be reconfigured as you need to make changes to the layout of your cleanroom, and offer many customization options.

Aerospace and defense cleanroom design should also include a powerful HVAC system as well as cleanroom lighting that integrates seamlessly with modular panels and facilitates proper airflow velocity. Additional features and cleanroom supplies can be added to customize the cleanroom to specific applications. Some of these additions might include air showers, a fire suppression system, laminar flow systems, and industry-specific equipment and furniture.

Aerospace cleanroom classification requirements can be complicated and difficult to reach without the right cleanroom design. When it comes to aerospace cleanroom design, you can trust Angstrom Technology to design, build, and install the best cleanroom for your unique application and classification. To get started, reach out to our professional design team today.

A new project means new requirements, new equipment, and maybe even new staff and higher stakes. If you need to redesign your aerospace cleanroom to meet the needs of a new project, you want to make sure to make the necessary changes thoroughly and efficiently so you’ll be ready to start the next endeavor off on the right foot. Let’s go over what you need to know when redesigning your aerospace cleanroom.

Aerospace Cleanroom Redesign Process

Before you start tearing into your cleanroom redesign, it’s important to start the process on paper. This means you need to make a plan for how your new cleanroom will operate, and then lay out the steps to get there. To do this, you’ll start with your cleanroom classification to figure out what’s needed, adjust the space to fit your new requirements, and make sure your systems can support the changes.

Consult Your Cleanroom Classification

Looking at your cleanroom classification, see if your new project requires more control over the environment than it currently has. If your new project is more sensitive to risks of contamination, requires more space to fit larger equipment or products, or more control to protect the safety of your workers, a cleanroom redesign is necessary. 

When consulting your new cleanroom classification, specifically look at the areas of particle count, air changes, and ceiling coverage as it relates to your ISO class number. If you need to meet new classification requirements, these are the main areas you’ll need to address. Keep in mind that if your cleanroom is changing size or layout, your airflow pattern will need to be adjusted accordingly in order to make sure all of the air is being filtered and replaced efficiently in your redesigned cleanroom.

Plan Your Cleanroom Redesign Needs

Once you have a basic roadmap of the changes you need to make to your cleanroom, take a look at your current space. Do you have enough room for your new project materials, products, personnel, and equipment? Does the cleanroom need to be reconfigured for a more efficient layout, or do you need a new cleanroom entirely? These are great questions to answer in the planning stage of your cleanroom redesign, as you don’t want to get halfway through the process to realize your current setup isn’t working. 

When addressing your space requirements, remember that too much space could also be an issue. If your cleanroom is too large for your new project needs, you’ll still be using the same amount of energy to heat, filter, and light the space. Downsizing or condensing your cleanroom can help cut operational costs — impressing your investors — and reducing the space you’ll need to keep clean.

Upgrade Your Cleanroom Systems

To handle increased air changes or filtration demands, your systems may also need to change to reach new requirements. For example, if your cleanroom is increasing its air change rate, you may need to increase the percentage of ceiling coverage by adding more filter/fan units. If your new project will be more sensitive to temperature or humidity changes, you may need to upgrade to a more powerful HVAC system for greater environmental control. 

Keep in mind that, since all the systems within your cleanroom work together, a change to one system will likely mean an adjustment for another. For example, increasing your filter/fan units may take up space that your cleanroom lighting used to occupy, so you’ll need to look for a new lighting solution that works around your filtration system.

Cleanroom redesign is also a good time to check in on your equipment and systems for service and upgrades. Since the cleanroom won’t be in operation for a short time, it’s a good idea to get cleanroom maintenance tasks out of the way during this window.

Customizing Your Aerospace Cleanroom Redesign

Once your cleanroom redesign addresses the essential functions of your new cleanroom, you can begin to customize it with other items. These are the things specific to your new project that will make it a success, which could include:

• Cleanroom furniture including workstations, tables, and storage solutions
• Pass through chambers and gowning rooms
• Extra systems like fire suppression or static control
• Additional environmental monitoring controls 

Your cleanroom redesign should cover the basic needs of your new project, such as meeting your new cleanroom classification, but also allow you to meet the new demands with a more efficient layout, upgraded systems and additional features. A successful aerospace cleanroom redesign will plan out all the changes first, and implement them efficiently so you can adapt to the changes seamlessly and hit the ground running with your new project.

Need to resize or reconfigure your aerospace cleanroom? Angstrom Technology has you covered. Our professional cleanroom designers can help assess your needs and space requirements to find the ideal layout and air flow pattern for your application. We also can help upgrade your HVAC and filtration systems to match your new cleanroom redesign. Get in touch with us today to get started.

Lighting is a critical part of cleanroom design. This system allows employees to properly view what they’re working on, improves the efficiency of your cleanroom operations, and can even help identify contaminants to help keep your cleanroom clean. Which cleanroom lighting is best for your application? Let’s explore your options to help you decide.

How to Choose Cleanroom Lighting

You’ll want to choose cleanroom lighting that is as illuminating as it is simple to maintain and clean. Additionally, consider the way your lights are mounted and how they work with your overall cleanroom design to help you reach your cleanroom classification. The cleanroom lighting you choose must be highly efficient and contaminant-free. The fixtures and any mounting mechanisms must be able to be cleaned effectively and ensure no contaminants can enter the cleanroom.

LED Cleanroom Lighting

LED lighting is known to be more durable and longer-lasting, require less maintenance, and use less energy than incandescent lighting. Plus, LEDs are extremely bright, which is a useful quality for aerospace cleanrooms where a lot of illumination is needed.

Cleanroom Lighting: Useful Measurements to Know

When choosing cleanroom lighting, you’ll need to understand how lights differ by comparing their measurements. Here are a few useful measurements to know:

Watts: measures how much energy is required to power the light

Foot-candles: measure the distance light reaches, by square feet

Lux: measure the intensity of light produced, as interpreted by the human eye

Lumens: measure light output

Depending on the use of light in your cleanroom, you will use these measurements differently. For example, if work in your aerospace cleanroom is task oriented and needs light to focus on small parts, you’ll require brighter, more intense lighting that allows significant illumination of the work area without causing employees to strain their eyes. Conversely, work over a broader area that isn’t detail-focused will need to prioritize area coverage, but not necessarily intensity.

Mounting Cleanroom Lighting

How lighting is mounted is another important part of choosing the right fixtures for your cleanroom. When comparing lighting systems, consider how much space the lighting system will occupy on the ceiling, a factor that is especially important when ceiling space must also be shared with filtration and fan units.

The way your cleanroom lighting is mounted will also determine how you access it to perform service such as replacing bulbs, fixing wiring, or cleaning the fixtures. Lighting can be mounted so that it is accessible from inside the cleanroom, but keep in mind this means all servicing of lights will interfere with cleanroom processes. Lights can also be installed from above. The advantage of this is that accessing lights does not mean as much of an interruption for the room below, and keeps contaminants from entering from the lighting space. However, this option requires more space above the ceiling for access.

Types of Cleanroom Lighting

Each aerospace cleanroom will have specific lighting needs and varying amounts of available ceiling space. Because of this, there are many different types of cleanroom lights to choose from. Here are a few common types of cleanroom lighting:

Flat Panels 

Flat panels are mounted flush with the ceiling. They provide a lot of light and are easy to clean. Because of their wide panel design, this cleanroom lighting type requires more ceiling space compared to other options, which makes it less than ideal for cleanrooms with stringent filtration requirements.

Teardrop Lighting

More stringent cleanroom classifications prioritize ceiling space for fan units and filters. Lighting, therefore, is a secondary concern and must work around the filtration system. 

Teardrop lighting extends below the ceiling to allow for precious ceiling space to be used for filtration. The teardrop shape allows an uninterrupted flow of air around the lighting without creating turbulence. The disadvantage of teardrop lighting is that it takes up valuable headspace within the cleanroom environment.

LED Lighting Grid

Batten lighting, or lighting strips, are linear LED lighting which is integrated with the ceiling grid system. This allows adequate space for fan/filter units around filters. Wiring for the lights is also built into the grid system so it provides consistent light throughout space without taking up a lot of room on the ceiling.

Recessed Lighting 

Recessed lighting units sit in the ceiling on a gasket to create an airtight seal. While they leave plenty of headroom, recessed lighting requires extreme care when servicing to ensure no contaminants are trapped when light is accessed. In cleanrooms with extremely stringent requirements, recessed lights and filtration can be combined in singular units for ultimate space-saving capabilities.

Expert Cleanroom Design and Lighting Help

An expert cleanroom designer will make choosing cleanroom lighting easier. They can work with you and your specific application to determine which types of lighting and mounting options will best complement your design needs. An cleanroom expert can:

• Help decide which lighting can be used to perform different tasks in your cleanroom — specific to your application and workers’ needs.
• Help design lighting to fit around other features of your cleanroom design, including filtration and mounted equipment.
• Allocate control panels where they are accessible and convenient for staff.
• Choose energy-efficient lighting fixtures that will maximize productivity while minimizing operational costs.

Cleanroom lighting is an essential part of your cleanroom design and should work with all the other elements to make a high functioning cleanroom for your application. If you’re still unsure which lighting option is best for you, talk to a cleanroom design expert about your concerns and specific project requirements.

Need a little help designing your cleanroom? Call the experts at Angstrom Technology. From lighting to flooring, we can help you make the best choices for your budget and your application. 

Aerospace cleanrooms require a high level of control. They can range from an ISO 14644-1 Class 5-7, which have vastly different requirements. At a minimum ISO Class 7, the cleanroom will require about 60-90 air changes per hour and need to filter out a range of particle sizes, including all but 352,000 of microns 0.5 or larger per cubic meter. The cleanroom’s filtration system, airflow pattern, and ceiling fan coverage all work together to reach these stringent cleanroom classifications. In addition to these components, there’s another system that is integral to maintaining control and supporting other factors of cleanroom design: the cleanroom HVAC system.

The aerospace cleanroom HVAC system effectively controls temperature, humidity, and ventilation within the space. It helps make sure all processes run smoothly and helps keep the cleanroom clean and efficient. Let’s explore the basic cleanroom HVAC requirements for environmental control of temperature, humidity, and ventilation, and how these three factors can play an important role in aerospace cleanroom operations.

Aerospace Cleanroom HVAC Temperature

A cleanroom HVAC system is crucial for controlling temperature within your aerospace cleanroom. It’s important to manage temperature, not only to keep employees comfortable but to maintain a stable environment. Some processes within aerospace cleanrooms generate significant heat and need to be balanced with proper cooling to prevent both staff and equipment from overheating. 

Temperature fluctuations could affect cleanroom operations if some equipment, parts, or materials are temperature sensitive. Some sensors or electronics will not function effectively in an unstable environment. Also, expanding and contracting as a response to temperature changes could affect manufacturing equipment or products and lead to failure.

The cleanroom HVAC system can fine-tune temperature to optimal levels and make adjustments as needed depending on operating needs and project requirements. NASA recommends an optimal temperature of 67-77°F in aerospace cleanrooms ISO Class 5-8. For less restricted aerospace cleanroom applications, higher temperatures up to 80°F are allowed.

Aerospace Cleanroom HVAC Humidity

Humidity can affect aerospace cleanroom operations from minor to major ways, from changes to paint drying time or consistency to the disruption of fine electrical parts or sensors. At a minimum, humidity in aerospace cleanrooms should be controlled to prevent condensation on surfaces, which could not only affect the performance of hardware within the cleanroom but also could attract surface particulates and contaminate products.

The HVAC system is responsible for regulating appropriate humidity levels within the controlled cleanroom environment. Humidity in an aerospace cleanroom should be 30% at minimum, and not exceeding a maximum of 50%.

Aerospace Cleanroom HVAC Ventilation

Proper ventilation is key to meeting stringent air change or air velocity requirements in an aerospace cleanroom. Optimal and consistent ventilation is essential for supplying the cleanroom with clean air, and is the foundation for all other systems to function effectively. Proper ventilation powers the cleanroom airflow pattern, limits airborne particles with the support of filters, and prevents surface particles from settling and contaminating the cleanroom environment.  

Airflow also creates a pressure differential. Positive pressure in aerospace cleanrooms helps prevent contaminants from entering the controlled environment, especially through small spaces in the structure around doorways, between panels, or other weak points. To achieve positive pressure, the cleanroom HVAC system will push more air into the cleanroom than is allowed out. Only a slight degree of pressurization is needed to achieve positive results.

Choosing the Right Cleanroom HVAC

Depending on your application, your aerospace cleanroom will have to meet a classification as well as specific industry requirements. These also stipulate control over environmental factors that could interfere with cleanroom operations. In addition to proper filtration and ceiling coverage of FFUs, your cleanroom HVAC system is important to maintaining a controlled environment. Establishing complete control over environmental factors like temperature, humidity, and ventilation, your cleanroom’s HVAC is a vital part to achieving project success. 

Depending on your application’s unique needs and cleanroom classification, a more powerful HVAC system might be required. Your capabilities within your cleanroom are determined by your collective systems’ ability to manage the environment, effectively change the air, and consistently remove particles to keep the space clean and contaminant-free. 

Is your existing cleanroom HVAC system powerful and efficient enough to meet your needs? Whether you’re shopping for a new HVAC or looking to update your existing one, Angstrom Technology can help! We understand aerospace cleanroom HVAC requirements and can help you get the most out of your system for full temperature, humidity, and filtration control. To have our experts assess your HVAC or go over your requirements for a new system, give us a call or reach out online.