Do I Need a Cleanroom?

If you’re researching Cleanrooms for the first time, you probably want a clear answer to one simple question: What problem do I have that installing a cleanroom could solve?

The simple answer is contamination control. In many high tech and life science industries, even a single particle of dust or one microbe smaller than the eye can see is enough to destroy an entire batch of product, which could lead to failing an audit or even a regulatory inspection, costing your company time and money in scrapped material, repeated work, quality investigations and remedial actions.

A Cleanroom is a made to measure, specifically designed environment offering filtration and air control that keeps airborne particles at extremely low levels. It protects processes and products that cannot tolerate the contamination found in a normal room.

A Cleanroom can extend to being far more than just a low particle room, it can be a fully controlled environment tailored to the exact needs of the process it protects. Depending on the product or application, a Cleanroom can precisely control environmental conditions such as regulating temperature, relative humidity and lighting levels.

The Invisible Enemy: Contamination

At normal room scales, dust is just an annoyance. In a cleanroom environment, it can be a disaster.

A human hair is roughly 100 micron (µm) in diameter. Many cleanroom standards control particles as small as 0.1 µm – that’s 1,000 times smaller than a hair’s width. For comparison:

• Pollen: 30 µm
• Bacteria: 0.3 µm
• Smoke particles: 1 µm

These tiny particles can carry bacteria, oils, salts or metal ions.

As an example, if a particle lands on a silicon wafer during semiconductor fabrication, it can cause defects that means chips fail. As a result, the semiconductor industry operates some of the highest classifications of Cleanrooms.

In pharmaceutical filling lines, a single viable microbe could contaminate an entire batch of injectable drugs.

In aerospace optics, a 1 µm particle on a lens could scatter light and ruin telescope performance.

Where Cleanrooms Are Essential

1. Semiconductor & Microelectronics: The nodes on today’s leading-edge chips, (3 nm and below), are smaller than many viruses. A single dust particle landing on a wafer during lithography can short circuit transistors and render an entire wafer useless.
2. Pharmaceuticals: The environment sterile medicines, e.g. injectables and eye drops, are manufactured in, must meet strict microbial and particulate limits. Regulatory bodies such as the MHRA in the UK and the FDA in the US regulate GMP (Good Manufacturing Practice) and the associated Cleanroom compliance.
3. Medical Devices: Implants e.g. pacemakers, stents, joint replacements, must be free of particulate and biological contamination to avoid infection and reactions once inside the body.
4. Aerospace: Satellite mirrors, laser gyroscopes and high-power optics can be ruined by molecular contamination or particles that cause scattering.
5. Life Sciences Research: Cell and gene therapy production and pathogen research often require Cleanroom environments.

How Clean Is “Clean”? The ISO 14644-1 Classification

Cleanrooms are classified according to ISO 14644-1:2015 by the maximum allowable concentration of airborne particles of specified sizes (from ≥0.1 µm to ≥5 µm) measured in particles per cubic metre of air, as shown in the table below.

The lower the ISO number, the cleaner the room.

Key Cleanroom Design Features

To achieve these particle counts, cleanrooms use several engineered systems:

• HEPA/ULPA filtration – High-Efficiency Particulate Air (HEPA) filters remove 99.97 % of particles ≥0.3 µm; Ultra-Low Penetration Air (ULPA) filters go even further for typically ISO 3–5 areas.
• Unidirectional (laminar) airflow – Air flows in one direction (usually top-to-bottom) at 0.3–0.5 m/s to sweep particles away from critical zones.
• Positive pressure cascading – Cleaner rooms are kept at higher pressure so air flows out when doors open, preventing dirty air ingress.
• Specialised materials – Non-shedding wall and ceiling panels, as well as internal furniture, sealed light fittings and specialist floors minimise particle generation.
• Strict gowning protocols – coverall suits, hoods, boots, gloves and sometimes face masks ensure humans, who shed millions of particles per minute, don’t contaminate the space. The exact gowning procedure will depend on the classification and process undertaken in the Cleanroom.

The Cost of Getting It Wrong

Real-world examples drive the point home:

• Wafer failures in the semiconductor industry can cost a manufacturing company millions of pounds.
• Pharmaceutical recalls due to visible particulates or microbial contamination can also be about financial cost but the main concern is cost to the patient. Patient safety is the ultimate driver in sterile pharmaceuticals.

Do You Actually Need a Cleanroom?

In practice, the conversation rarely covers “Do we feel like spending money on a cleanroom?” It should be driven by an unavoidable requirement.

Most clients approach Angstrom Technology for one of three reasons:

1. Regulatory or industry-standard mandate: If you manufacture sterile pharmaceuticals or certain medical devices in the UK/EU, EU GMP Annex 1 states explicit requirements for your cleanrooms. Non-compliance can lead to regulatory action.
2. Customer or supply chain specification: Semiconductor, aerospace, and optics customers routinely write ISO class requirements into their purchase contracts. A wafer fab or satellite component supplier that cannot demonstrate certified Cleanrooms to the specified classifications simply does not get on the approved vendor list.
3. The product physically will not work otherwise: If a wafer in semiconductor is contaminated with a particle it will fail, hence the Cleanroom is required.

Final Thoughts

If you’re starting a new project involving semiconductors, sterile pharmaceuticals, medical devices or advanced optics, the question is no longer “Do we need a cleanroom?” but rather “What classification and layout do we need to protect our product and stay compliant?”

Angstrom Technology’s expert cleanroom design and build team can help you answer exactly that.