Why Most Cleanroom Contamination Comes from People

What is cleanroom contamination?

Cleanroom contamination is the introduction of particles in a controlled space, which can compromise sensitive applications and products. ISO 14644 and EU GMP set the standard for the appropriate levels of airborne particles at both ‘at-rest’ and ‘in-operation’ states, and it’s the cleanroom operator’s responsibility to maintain cleanliness within these limits.

There are two types of cleanroom contamination, each posing their own set of risks and consequences:

• Viable contamination: Living micro-organisms that grow and multiply, including bacteria, fungi, and yeast.
• Non-viable contamination: Non-living particles including dust, skin cells, debris, and material fragments.

Cleanroom contamination can occur through several means, including particle generation from equipment, a by-product of your applications, the use of incorrect consumables, and flaws in procedures. However, the leading cause of cleanroom contamination comes from personnel, accounting for approximately 75%⁽¹⁾.

Why are humans the biggest source of cleanroom contamination?

Cleanroom personnel are vital for operating and maintaining a cleanroom, and despite the advancement of technologies, they can perform fragile and precise tasks better than robotics. However, humans are walking contaminants and widely recognised as the leading cause of contamination within a controlled environment, contributing to approximately 75%⁽¹⁾ of all particles found within the atmosphere and on surfaces.

Humans are a leading cause of contamination due to three key factors: what we are, what we do, and what we have. They continuously release and introduce particles into the controlled space, from skin flakes, hair shedding, respiratory emissions, and microbes found in and on the body. Steps are taken to reduce this, with cleanroom garments designed to trap and retain bio-contaminants from entering the controlled space, including coveralls, face masks, gloves, overshoes, and goggles being the most popular, with restrictions on accessories and toiletries not suitable for cleanroom use, including jewellery, deodorants, and cosmetics.

The other contribution of human-introduced contamination includes poor practice and behavioural errors within the cleanroom; when identified and addressed, this improves and strengthens your contamination control strategy.

The top 5 common human errors that cause cleanroom contamination

1. Inadequate techniques: Failure to follow cleanroom best practices and processes (especially in relation to gowning, hand hygiene, and surface cleaning) can lead to a contamination incident within a controlled space. Everything, from how an operator gowns before entering a cleanroom to the direction an operator wipes or mops a surface, must follow a methodical technique that’s proven to maximise the prevention or removal or contaminants.
2. Movement speed: Often an overlooked behaviour, but the speed in which your operators move around the controlled space can significantly disrupt the airflow that your cleanroom works hard to produce. A fast pace or uneven movements can cause a contamination vortex which keeps particles trapped in the air rather than being pushed down-and-out by the fan filter units (FFUs). Slow, intentional movements following a well-curated workflow will keep airflow disruptions to a minimum.
3. Complacency: When operators become too comfortable with, or indifferent to, strict contamination control processes, this increases the risk of a contamination incident and even creates an unsafe working environment. Repeatedly performing the same tasks can lead to operators running on autopilot, losing focus, and potentially bypassing important, necessary steps.
4. Inconsistent behaviour: Inconsistencies amongst your operators is another cause of cleanroom contamination – whether this be varying ways or working, gaps in knowledge, a lack of/outdated SOPs, or conflicting training/onboarding processes. All operators must be on the same page when it comes to your cleanrooms processes, with a clear understanding of the procedures, and regular, uniform reinforcements of these to keep everyone aligned.
5. Lack of awareness: Unawareness of best practices, industry-recommended techniques, regulation guidance, and consumables/material compatibility can all lead to unwitting errors and contamination incidents. Keeping your personnel informed on the latest guidance and best practices can fill knowledge gaps and upskill your workforce to effectively combat contamination risks.

How operator training can reduce cleanroom contamination

A cleanroom’s performance is only as effective as the people operating within it. Ensuring your personnel are equipped and informed on cleanroom protocols and best practices is crucial for keeping cleanroom contamination to a minimum.

Cleanroom operator training shouldn’t be seen as a tick-box exercise; it’s a strategic approach to minimising contamination, maintaining application integrity, and also protecting your people. Under EU GMP, it specifies:

“The manufacturer should provide training for all the personnel whose duties take them into production and storage areas or into control laboratories (including the technical, maintenance and cleaning personnel), and for other personnel whose activities should affect the quality of the product.” ⁽²⁾ – Volume 4, Chapter 2

Cleanroom training shouldn’t be a one-and-done exercise; it should be a recurring resource for all cleanroom operators to support with establishing the correct behaviours and best practices. With a combination of interactive workshops, informative tutorials, practical demonstrations, and actionable takeaways, cleanroom operator training can help you:

• Standardise behaviours and set expectations
• Reinforce correct techniques
• Establish safety and protection for your personnel
• Meet compliance requirements (ISO and GMP)
• Minimise the risk of contamination and downtime
• Maintain product integrity
• Boost company reputation and commitment to quality

While it’s inevitable that humans will cause contamination within a cleanroom, it’s important to find a balance between creating an environment that fosters a productive working environment for your operators and implementing contamination control principles – many of which will be very unique to your specific environment. Understanding and identifying the common behavioural errors allows mitigation steps to be implemented to reduce the risk of an incident.

At Connect 2 Cleanrooms, CPD-certified cleanroom operator training will educate your team on the correlation between the correct implementation of protocols and contamination control. With a mixture of theory, tutorials, and practical workshops, our courses will help you control the introduction, generation, and retention of particles in line with EU GMP and ISO 14644 standards.

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⁽¹⁾ DuPont (2023) EU GMP Annex 1 Guide for Cleanroom Garments. Available at https://www.dupont.co.uk/content/dam/dupont/amer/us/en/personal-protection/public/documents/en/EU_GMP_Annex_1_Guide_For_Cleanroom_Garments_2023_EN.pdf

⁽²⁾European Commission (2014) EudraLex – Volume 4: EU Guidelines for Good Manufacturing Practice for Medicinal Products for Human and Veterinary Use, Part 1, Chapter 2: Personnel. Available at: https://health.ec.europa.eu/document/download/11f4f8e6-a6e9-4897-afe3-f21e1dc56cb8_en?filename=2014-03_chapter_2.pdf