Cascading Cleanroom Pressure: Explained

Cascading Cleanroom Pressure: Explained

You probably already know how important proper air filtration is in meeting your cleanroom’s ISO requirements. But what you may not realize is how important some other environmental factors are as well. Things like temperature, humidity, static, and pressure all need to be controlled in order to ensure a clean, hazard-free space for your sensitive operations. 

In this article, let’s take a closer look at airflow design and pressure — specifically cascading pressure. We’ll discuss what it is, why it matters, and when it’s needed. 

An Overview of Cleanroom Airflow Design & Pressure

If you have a baseline knowledge of cleanrooms, you may already know about airflow design and the two most common types of cleanroom pressure: positive pressure and negative pressure. If you don’t, we’ll break these concepts down for you: 

  • Positive pressure means the air pressure inside your cleanroom is greater than the pressure outside of it. Achieved by pumping filtered supply air into your cleanroom, this helps prevent harmful particles from entering and disturbing sensitive applications. The general rule of thumb here is that more supply air is coming into the cleanroom than is being exhausted out of it.  
  • Negative pressure means the air pressure inside your cleanroom is lower or less positive than the pressure outside of it. This prevents harmful particles from escaping or exiting to other critical spaces and damaging external environments. The general rule of thumb here is that more air is being exhausted out of the cleanroom than is being supplied and coming into it. You may think of it like a vacuum working to remove hazardous particles.   

Find more details on the difference between positive and negative cleanroom pressure here

What Is Cascading Pressure in a Cleanroom?

Most facilities and cleanroom suites require a specific airflow design, specifically known as cascading pressure. Cascading pressure means the most stringent cleanroom zone has the highest level of pressure, and the least stringent cleanroom zone has the lowest level of pressure. This is to ensure the flow of contamination is from clean to less-clean. In other words, there are pressure differentials in each of the zones within a cleanroom suite, based on how strict their cleanliness requirements are. 

Why Is Cascading Pressure Needed in a Cleanroom? 

Proper airflow design and pressurization is essential for facilities with cleanroom suites, or cleanrooms that have multiple rooms and/or zones within them, to control contamination. Typically, the tasks that are carried out within these zones require different levels of cleanliness and environmental control. Therefore, cascading pressure is needed to ensure air flows in a way that prevents particles from entering the cleaner zone, or most controlled space, in the suite. 

That said, airflow design is an important consideration for you to make before your cleanroom and associated technologies are installed. Talk with your cleanroom manufacturer to figure out the most effective, safe process flow for your applications and how best to monitor the airflow within the cleanroom. They’ll work with you to determine which zones should accommodate certain tasks, and how pressure should flow throughout them to best protect personnel and material processes. 

How to Monitor Cleanroom Airflow and Pressure in Between Zones

So you’ve designed your cleanroom suite to accommodate optimal airflow and pressure — but your work isn’t over yet. In order to ensure consistently controlled operations, you need to regularly measure and monitor airflow and pressure levels. 

Luckily, there are a few tools and technologies that make this process an easy one, including: 

  • Differential pressure gauges, which measure and visualize the difference between two pressure points within your cleanroom suite. 
    • Magnehelic or analog gauges, which have a needle pointer or dial that senses the differential in air pressure and responds to the change in pressure between the adjacent spaces. The pressure reading is displayed. 
    • Digital pressure gauge, which senses the differential in air pressure and responds to the change in pressure between the adjacent spaces, and is then converted to an electronic signal, shown using a digital display.
  • Distributed sensor modules (DSMs), which are network-accessible modules used to monitor room differential pressure, and in some cases temperature and humidity as well. The output of the sensor is an analog signal that can be fed to a console or interface card for monitoring and control. One great benefit of these modules is that they can be connected to your building management system (BMS), so measuring and monitoring cleanroom airflow and pressure is in one cohesive system where all the readings are in one place.

Need Help With Your Next Cleanroom Project? Contact Us

If you have questions related to pressure or any other cleanroom-related topic, don’t hesitate to contact us at Angstrom Technology. Our team is full of skilled, friendly experts who are happy to provide the answers you need. And as an industry leader in cleanroom design and installation, we’re able to tackle whatever specifications your cleanroom project may require. 

4 Microelectronics Manufacturing Applications that Rely on Cleanrooms

4 Microelectronics Manufacturing Applications that Rely on Cleanrooms

Microelectronics manufacturing often involves delicate materials and occasionally toxic substances that require special care for handling and storage. Manufacturing equipment is also highly sensitive and generates heat which must be controlled. 

For applications in microelectronics manufacturing to be successful, a high level of control is required over the manufacturing environment. A cleanroom allows regulation of environmental factors like temperature, relative humidity, air quality, static electricity, and more. They are often necessary for microelectronics manufacturing applications to ensure quality and consistency.

Lets look at 4 specific applications of microelectronics manufacturing and how a specialized cleanroom can help achieve their goals.

#1 Semiconductor Cleanrooms

Semiconductors are used to make nearly every piece of technology we rely on today — from cell phones to coffee machines to vehicles. To make the complex microchips these devices need to function and respond with the speed and accuracy modern life demands, they require semiconductors to be meticulously manufactured and assembled. 

As the demand for technology continues to rise, semiconductor manufacturers must produce more without sacrificing quality. That’s where a semiconductor cleanroom proves its worth. A strictly controlled environment streamlines the manufacturing process and significantly reduces risk to safety and productivity by limiting particle count and size, temperature fluctuations, relative humidity, and other factors that commonly threaten semiconductor production.

#2 Silicon Wafer Manufacturing Cleanrooms

Silicon wafers are delicate but powerful products that are an essential part of semiconductor devices. Their ability to conduct electricity in a controlled manner makes them highly prized for fine electronics. Silicon used for semiconductors is grown first as an ingot with other elements called dopants, then precisely cut to form thin wafers which are used to produce microchips and other semiconductor applications.

The process of manufacturing silicon wafers requires extreme care. Particularly in the polishing stage of the process, where chemical slurries are used to remove any imperfections on the surface of the silicon wafer, protection from contaminating particles is critical. Polishing must typically be conducted within a cleanroom that meets the standards of ISO Class 5 at minimum to protect both products and personnel during this stage.

#3 SMT Assembly Cleanrooms

Surface-mount technology (SMT) assembly involves automated machinery which connects electronic components to printed circuit boards. These machines use a soldering paste to place and attach the components. SMT assembly must take place in a controlled environment to allow the equipment to work at an optimal level of efficiency. 

An ISO Class 7 or 8 cleanroom is common for this microelectronics manufacturing application. A powerful cleanroom HVAC system regulates environmental factors to offset heat generated by machinery and fan filter units remove contaminants and deliver clean, filtered air into the space.

#4 Solar Technology Cleanrooms

Solar cells are used to make electronics that capture the sunlight and convert it into electricity. Before they can be used in a solar panel, they start as a thin slice of silicon and other conductors. Silicon wafers are used to develop solar cells through a complex process of texturing, etching, acid cleaning, and diffusion. Each step in the process requires strict control, as any interfering particles could compromise the product.

Cleanrooms are invaluable in the process of manufacturing solar cells — meeting ISO Class 5 – Class 7 standards. As the silicon wafer is refined, extra care must be taken to ensure that particles cannot damage the semiconductor or disrupt its delicate purposes. A cleanroom using HEPA and ULPA filters can help prevent product failures and secure success for solar cell projects.

Cleanroom Design for Microelectronics Manufacturing

Semiconductor cleanrooms and similar applications use carefully designed systems to regulate temperature and humidity. A robust filtration system limits particles which could interfere with equipment or compromise products. Other cleanroom systems like ESD-safe materials and fire suppression work to protect personnel in the space from the hazards of their work. All components of the cleanroom must also not contribute to the environment by shedding particles or outgassing and must be easy to clean completely.

When properly designed and built, cleanrooms offer a great value to semiconductor manufacturing and other applications involving microelectronics. If you need a cleanroom capable of keeping up with you and your microelectronics manufacturing goals, let us know. We’re happy to design, manufacture, and install the cleanroom that fits your classification and your application.

Do You Need A Soundproof Cleanroom?

Do You Need A Soundproof Cleanroom?

A cleanroom can be designed to meet the needs of almost any application with any requirements, from controlling static and humidity to even controlling sound. You probably know whether your application requires control for things like humidity and static, but what about sound. Do you need a soundproof cleanroom? Here are some conditions where you might.

Loud Manufacturing Environments

If your facility is a manufacturing environment that requires protective hearing equipment like earplugs ear, soundproofing your cleanroom is a good idea, especially if hearing protection isn’t necessary for your cleanroom processes. Hearing protection might even hinder those processes, as foam from earplugs and earmuffs can hold and shed particles.

If your cleanroom contains the loud equipment and the rest of your processes outside the cleanroom don’t require hearing protection, it can be worthwhile to soundproof your cleanroom so that hearing protection is only required inside. This can greatly reduce hearing-related injuries to your personnel and reduce the cost of hearing protection for your company.

Loud Equipment Containment

If you have a piece of equipment or pieces of equipment that are particularly loud, rather than creating a soundproof cleanroom, a more efficient solution might be creating a soundproof containment room for that equipment. A modular soundproof room can be created around a loud piece of equipment. The benefit to this is reduced noise and need for ear protection in your facility. Additionally, modular containment rooms can be freestanding or can incorporate your existing structure, so no matter where a piece of equipment is housed, it can be soundproofed.

Sensitive Processes

If your cleanroom operation is a particularly sensitive process, a soundproof cleanroom may also be beneficial. Sound is vibration, and delicate operations may be affected by loud noises and strong vibrations, which a soundproof cleanroom can reduce.

Proprietary Information

If your cleanroom operations are top secret or deal with proprietary information which should not leave the walls of the cleanroom, a soundproof cleanroom can also prevent the unplanned and unwanted spread of information by containing sound within the cleanroom.


Angstrom Technology’s modular cleanrooms and in-plantinplant buildings can be customized to control sound, if your application requires. Get in touch with one of our design engineers to discuss your project.


Why You Need a Cleanroom, Not Just a Lab

Why You Need a Cleanroom, Not Just a Lab

When you’re in manufacturing, whether you’re dealing with pharmaceuticals, food, or even industrial products, quality is always a critical concern. When quality control matters, you have to test products, and most of that testing likely occurs in a lab. Some products will even need to be manufactured in a laboratory setting. But is your lab the right environment to ensure quality in your manufacturing processes? If it’s just a lab in name only, and not a true cleanroom, it might not be.

What’s the difference between a lab and a cleanroom?

A laboratory is a space dedicated to scientific research, experiments, and testing, as well as the manufacture of certain types of products. There is nothing in this definition that requires the laboratory environment to be controlled in any way. While a pharmaceutical manufacturer might have a highly controlled laboratory environment, a local high school might also have a lab, wherein students conduct experiments under no environmental controls.

A cleanroom is a controlled environment, specifically one that controls the level of contamination from particles, along with other factors such as temperature, humidity, static, etc. Controlling all of these variables protects your processes and products from contamination or conditions that could compromise the integrity of those products and processes.

Cleanrooms are required to meet specific standards as to the number of particles acceptable within the space, and to meet that standard, the cleanroom is regularly tested. Equipment and systems are put in place to maintain the cleanroom environment, including air filter systems and air flow systems, as well as procedures for entering and using the space, from special chambers called air showers that blow contaminants off of personnel before they enter the cleanroom to requiring lab coats or gowns for personnel working in the cleanroom.

Why do you need a cleanroom instead of just a lab?

If you’re not controlling your lab environment, there’s really no point in having one. It’s not going to ensure product quality, integrity, and safety—and those things are all necessary for a sound manufacturing process. For certain industries, like semiconductor manufacturing, pharmaceutical manufacturing, and aerospace and defense manufacturing (just to name a few of the many industries that use cleanrooms) cleanrooms are either required by law or are enforced as an industry standard. For example, automotive manufacturing cleanrooms are generally required to meet ISO Class 7 or 8 standards in order to meet the supplier requirements of the OEMs they work with and to ensure the quality of their products.

Is it time to upgrade your lab to a cleanroom? Get in touch with the cleanroom experts at Angstrom Technology.


New Trends in Cleanroom Design

New Trends in Cleanroom Design

Now that the holidays are over and the new year has begun, you might finally be getting around to implementing a new cleanroom in your facility. If you’re designing a new cleanroom or updating your current one, here are the latest trends in cleanroom design that you should consider as you design your cleanroom space.



Sustainability is an important consideration for all of us, including corporations. Because cleanrooms use so much energy to maintain the desired environmental conditions, engaging in sustainable practices when possible is crucial. Not only do these sustainability efforts support the natural environment, they are also energy efficient, which can help you save on energy costs. Using energy efficient equipment and energy efficient LED lighting can aid in sustainability efforts, as can a modular cleanroom. Modular cleanrooms can be altered and right-sized as the needs of your company change, while reusing the modular components, and require less material than traditional construction. Additionally, modular cleanrooms can make use of the currently existing HVAC and ventilation systems in your space, rather than requiring separate systems.



Now, more than ever, we’re aware of the value of transparency from leaders and companies. When it comes to your cleanroom, the primary concern will always be the integrity of the controlled environment within, and it may also be important to maintain privacy for the safety of intellectual property, but cleanrooms can benefit from some openness and visibility. Using transparent partitions in the place of opaque walls can provide some benefits, the biggest of which being that lab processes can be observed, whether by compliance regulators or supervisors within your organization, without disturbing cleanroom processes or the environment within.



Many organizations are resisting the use of specific dedicated spaces for certain tasks or operations, instead opting for more shared spaces and flexibility in order to reduce costs and under-utilized space. This means incorporating fixtures and furniture, such as lab benches and workstations, into your cleanroom that can accommodate a variety of tasks or processes, as well as modular cleanrooms that can be easily expanded, contracted, or reconfigured to maximize use of space.


As you’re working on your cleanroom design or redesign, consider the needs of your company and your cleanroom, as well as how the cleanroom can continue to meet those needs over time, with organizational and regulatory changes. Incorporating sustainability, transparency, and flexibility into your cleanroom design can make your cleanroom efficient and future-proof, not matter the changes to come.

Looking to design a new cleanroom? Get in touch with the cleanroom experts at Angstrom Technology.

Benefits of Cleanroom Pass-Through Chambers

Pass-through chambers are a commonly used cleanroom term, and they’re also an ideal addition to just about any cleanroom. They’re easy to install, they don’t draw much out of your budget, and they hold tons of benefits for the operation of your cleanroom. While there are all types of pass-through chambers, from basic transaction windows to industrial roll-up door pass-throughs, most cleanroom pass-throughs fall into the dual-door category. Because the removal of contaminants is any cleanroom’s top priority, most cleanroom pass-through chambers have two doors, one on the outside and one on the inside of the cleanroom. Those cleanrooms that must meet higher standards often install pass-throughs with additional features like an air shower or fire resistance, but the general construction and operation is the same.

What are the benefits of cleanroom pass-through chambers?

  • They allow your employees to transfer materials in and out of your cleanroom without contamination.
  • They make it easy for employees to pass materials into the cleanroom without having to gown. This also cuts down on the number of employees in your cleanroom at any one time.
  • They come in a variety of sizes and materials, ensuring you get the pass-through that meets the needs of your employees. Stainless steel options are corrosion-free, which extends the life of your pass-through, and helps keep your cleanroom clean.
  • Double door designs ensure cross contamination doesn’t happen. And heavy duty sealing lock features keep contaminants out of the chamber when it’s not in use.
  • Most pass-through chambers are customizable, allowing you to choose the option that best fits the needs of your cleanroom. Whether you need a fire safe option, one that’s chemical resistant, or a pass-through chamber that includes a blower with HEPA filtered air, you can choose the chamber that best suits your cleanroom needs, ensuring you benefit from a pass-through chamber, regardless of your cleanroom classification.

How do cleanroom pass-through chambers increase productivity?

The single greatest benefit of a cleanroom pass-through chamber is its ability to speed up your processes and increase employee productivity. Pass-through chambers eliminate the need for employees to properly gown to enter a cleanroom environment just to hand off a necessary item or sample. As you likely know, the gowning process can be time-consuming, and additionally, the more employees you have in a cleanroom, the greater the chance for contamination. When employees can simply place materials in the pass-through chamber, you save a great deal of time on both sides of the cleanroom. Best of all, pass-through chambers are easily installed, whether you have an existing cleanroom or you’ve just commissioned a new one.

Who uses pass-through chambers?

The benefits of pass-through chambers are clear. They boost productivity without sacrificing cleanliness. So, which cleanroom industries use pass-through chambers, and how?

Research Facilities

Because research facilities often study new and unpredictable chemicals and substances, they need pass-through chambers for safety more than for convenience. Because some chemicals can easily become volatile and cause fires, fire safe pass-throughs are commonly used in this application. These pass-through chambers can withstand fire exposure for up to 90 minutes, and their sturdy construction maintains frame shape that protects research labs from destruction. While these labs also often make use of air shower pass-throughs to decontaminate materials before they’re introduced to the lab, fire safe pass-throughs are the most common.

Medical and Pharmaceutical cleanrooms

Decontamination is the first priority of both medical and pharmaceutical cleanrooms. Because hospital laboratories often deal with highly contagious substances, it’s paramount that the environment remains sterile. In the same vein, pharmaceutical cleanrooms have to ensure there is absolutely no contamination in the manufacturing process that could alter their product. In both cases, these cleanrooms require pass-through chambers that keep samples, specimens, and other materials sterile as they’re brought into the cleanroom. These industries typically make use of a standard two door pass-through chamber that keeps outside contaminants from entering the cleanroom and ensures the materials remain sterile as they’re waiting to be brought in.

Electronic and technology manufacturing cleanrooms

Manufacturing facilities that put together the complex inner workings of technological devices like computers and smartphones require very strict cleanroom environments that filter out even the smallest particles of dust and other contaminants. Just one tiny particle settling on a single piece in the manufacturing environment could render a future hard drive useless. Many electronic and technology manufacturing cleanrooms opt for highly monitored pass-through windows in order to maintain the sterility necessary to produce quality electronic products while maintaining a high level of productivity.


Pass-through chambers are a highly useful component of any cleanroom. They help you ensure that you keep your processes moving, while maintaining the high standard of cleanliness within your cleanroom. If you’re installing a new cleanroom, or even if you’re considering adding a pass-through chamber to your existing cleanroom, be sure to give the experts at Angstrom Technology a call! We’ve been manufacturing top-of-the-line cleanrooms for years and would be more than happy to help you find the pass-through best for your operation. Call our office at 888-768-6900 or contact us online today!