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ISO 7: Defining Cleanroom Classification Guidelines

ISO 7: Defining Cleanroom Classification Guidelines

An ISO 7 cleanroom, also known as a Class 10,000 environment, is a controlled space engineered to limit airborne particles measuring 0.5 microns or larger to 352,000 per cubic metre by utilising 30 to 60 HEPA-filtered air changes per hour.
Published: 17 September 2021

What is an ISO 7 Cleanroom?

An ISO 7 cleanroom is a specialised controlled environment designed to regulate the concentration of airborne particulates. Under the international ISO 14644-1 standard, a cleanroom is defined as an enclosed space engineered, constructed, and operated to strictly limit the introduction, generation, and retention of microscopic particles.

To achieve official ISO 7 classification, the environment must meet precise contamination thresholds when tested with a light-scattering particle counter. The air within the suite must contain fewer than the following maximum parameters:

  • Particles 0.5 microns or larger: Maximum of 352,000 per cubic metre.
  • Particles 5.0 microns or larger: Maximum of 2,930 per cubic metre.

Cross-Standard Equivalents

Depending on your industry or geographic region, you may hear an ISO 7 cleanroom referred to by alternative regulatory frameworks:

  • US Federal Standard 209E: Known traditionally as a Class 10,000 cleanroom.
  • EU GMP Annex 1: Equivalent to a Grade C classification, frequently specified for sterile pharmaceutical manufacturing stages.

Before finalising a facility design, it is critical to perform a thorough evaluation to identify the exact size and volume of particulates that could negatively impact your specific application, experiment, or manufacturing yield.

ISO 7: Defining Cleanroom Classification Guidelines

Why Do Industries Require an ISO 7 Cleanroom?

The ISO 7 classification is deployed across a vast array of technical sectors where sub-micron particles can compromise product integrity, safety, or functionality.

High-Specification Manufacturing

In electronics fabrication and advanced engineering (particularly facilities working with advanced composites), minor dust contamination can cause microscopic short circuits or structural weaknesses.How To Get an ISO 7 Cleanroom?

Life Sciences and Healthcare

Medical device manufacturers rely on ISO 7 environments to prevent particulate contamination on components that interact directly with patients. In the pharmaceutical sector, Grade C/ISO 7 spaces are heavily utilised for product filling lines and the preparation of solutions that face an elevated risk of environmental contamination.

Depending on your technical tolerances, you may find a more cost-effective solution in an ISO 8 cleanroom, whereas operations requiring higher precision will need to transition up to an ISO 6 cleanroom.

Technical Design and Construction Criteria

The ISO 7 cleanroom is the most frequently specified classification in modern industry. Because it requires fewer air changes than ultra-clean tiers (such as ISO 5), it offers a highly cost-effective balance between initial construction capital and ongoing operational energy consumption.

Key engineering requirements include:

  • Airflow Volumetrics: An anemometer is used to verify that the facility achieves between 30 and 60 air changes per hour (ACH) using high-efficiency HEPA filtration.
  • Pressure Dynamics: The layout must incorporate a physical airlock at all entry points. This configuration enables precise control over incoming and outgoing air to maintain a constant internal positive pressure boundary of +25 to +30 Pascals.
  • Structural Materials: Common options include hardwall panels, monobloc systems, PVC, and glass. The defining requirement is that all internal surfaces must be perfectly smooth, non-porous, and highly resilient to aggressive chemical detergents to allow for straightforward decontamination.

Operational Maintenance and Protocols

Preserving the structural integrity of a Class 10,000 environment requires an ongoing commitment to facility care, rigorous environmental monitoring, and strict personnel discipline.

Core Maintenance Pillars

  • Continuous Positive Pressure: Preventing unfiltered external air from migrating into the clean zone.
  • Strict Material Controls: Restricting the types of items allowed inside the facility.
  • Mandatory PPE: Ensuring all staff act as effective barriers against human shedding.
  • Scheduled Plant Audits: Conducting routine filter evaluations and airflow checks.

Essential Cleanroom Do's and Don'ts

  • Do clean and wipe down all internal surfaces systematically in accordance with your validated SOP.
  • Do ensure all access doors remain completely closed to preserve the positive pressure barrier.
  • Do thoroughly sanitise all machinery, tools, and components before introducing them to the cleanroom.
  • Do confirm that all operators wear full Personal Protective Equipment (PPE) over their standard clothing prior to entry.
  • Don't bring non-essential items or unapproved materials into the controlled zone.
  • Don't overload or crowd the floor area, as this disrupts the engineered airflow paths.
  • Don't permit consumption of food, drinks, or gum inside the facility.
  • Don't turn off the HEPA fan filter units, as cutting the power compromises pressure boundaries and allows airborne particles to settle.

Are you looking to install or upgrade a controlled environment? Contact our specialist engineering team today to review your project requirements and design options.

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Peter Phillips
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I knew of Toni and her team from around 2003 and the days of their Clean Tent business. With a small new business that needed a clean room, I went straight back. Very helpful discussion with Toni led me to choosing a custom lamina flow hood (cheaper!) which was delivered bang on time, immediately passed an ISO 1385 audit and has been cheerfully maintained ever since. I'd go back to ISOClean because they know their stuff and do what they say.

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ISO Cleanroom were very easy and practical to work with. Both Toni and Amaleed were knowledgeable and very flexible - looking forward to working with them in for future projects.

Siobhan Carey
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I recently contracted Iso Cleanroom to design and build two modular ISO Class 6 cleanrooms so that our small orthobiologics company could implement in-house manufacture. They delivered on all of their commitments on cost, schedule and quality with no fuss. They showed up they day they said the would and finished up the day they said they would. They were extremely organised and meticulous, and helped us to address some unforeseen issues that cropped up during the installation.

Gareth Evans
StarStarStarStarStar

We contracted ISO Cleanroom to design, build and validate a large cleanroom in our new facility. Toni really knows her business, and was very helpful through the design process, enabling us to make the most of the available space. When it came to installation, Anthony and his team did an exceptional job, keeping the install to schedule. We are very happy with the professional service we have had from ISO Cleanroom and would not hesitate in recommending others to use them for any cleanroom requirements.