Cleanroom validation is an essential part of ensuring that cleanroom facilities are operating at the levels of cleanliness required by facility owners, their customers and perhaps external regulatory bodies. However, there are multiple standards for clean room performance; in addition, facility owners can specify variations from the main classes of cleanroom to meet the needs of specific applications.

Here we look at the overall purpose of behind clean room validation and the numerous factors which can affect what standards are set for different types of cleanroom.

The Purpose of Cleanroom Validation
Cleanroom certification, or validation, can be seen as “passing a test”, allowing the facility to continue to operate and be productive. But in fact, cleanroom validation is really about quality control, for instance:

– Ensuring purity and/or sterility of pharmaceutical or food production
– Preventing damage to sensitive electronics through exposure to particulates
– Ensuring reliable test or experimental results by preventing external contamination of samples

Facility owners are therefore highly motivated to ensure ongoing compliance to whatever standard has been specified for a particular clean room. For many facilities, cleanroom compliance is a business critical factor, with both reputation and profitability at stake. As a specialist clean room services company Tecomak fully understands the importance of not just giving a stamp of approval, but in helping facility owners maintain actual levels of cleanliness. For Tecomak and our clients, clean room validation is therefore part of a much wider process of ongoing monitoring, testing and maintenance.

Cleanroom Validation Standards
ISO 14644-1 (Classification of air cleanliness) is a global standard defining a range of classes of cleanroom, specifying the expected particle count per particle size for each class. However there are a number of other commonly used cleanroom standards used throughout the world. In the UK, cleanrooms can also be classified according to BS 5295 (1999) and EU GMP (2008), which applies across Europe. Each standard has its own grading system, often reflecting the best available cleanroom technology at the time the standard was specified.

ISO 1 class is the cleanest, with an allowable particle count of just 10 per m3 at 0.1µm and just 2 per m3 at 0.2µm. This type of facility is extremely rare and would be used only for the most sensitive research and development work involving, for instance, semi-conductors or bio science.

ISO Class 1 is significantly cleaner than the cleanest cleanroom specified by either the BS 5295 standard or the EU GMP standard, whose highest grade cleanrooms equates approximately to ISO Class 3 and ISO Class 5 respectively.

An ISO Class 5 facility is considered a high grade cleanroom and is typically required for aseptic applications such as sterile filling of pharmaceutical products into containers, for example. It allows up to 100,000 particles of 0.1µm and up to 3520 particles of 0.5µm per m3. An ISO Class 5 cleanroom equates to EU GMP class A and B, and BS 5295 Class E and F.

An ISO Class 7 facility can have an unrestricted number of small particles (0.1µm to 0.3µm) but must have no more than 352,000 particles at size 0.5µm and no more than around 2,900 particles at 5µm. This equates to an EU GMP Class C facility or a BS 5295 Class J facility and would typically be used for sub-sterile pharmaceutical processes.

An ISO Class 8 cleanroom is permitted up to 3,520,000 particles at size 0.5µm and 293,000 particles at size 5µm, equating approximately to EU GMP Class D or BS 5295 Class K. This level of cleanliness would be used for less sensitive applications where sterility is not an issue but where it makes general sense to maintain a good level of hygiene, such as packaging or storage of pharmaceuticals.

However, while these classes provide a starting point for saying what standards are required for a particular cleanroom, they do not give the full picture. Actual standards are set by a combination of different factors relating to the specific application, and may fall somewhere between the levels specified in these standards.

Factors Affecting Cleanroom Standards 
In practice, there are a number of influences on what standard of cleanliness is required for any specific cleanroom. These include:

– Industry wide regulatory bodies may decide to impose specific requirements (e.g. MHRA for medical applications). In such a case, cleanroom validation serves a dual purpose – to maintain MHRA approval and to assure facility owners that performance is to expected levels.

– Customer requirements – as part of ensuring the quality of their own supply chain. In this case, a customer may wish to see evidence of validation and other test results as part of the customer-supplier relationship.

– Specific processes being carried out within the clean room, carrying their own recommended levels of cleanliness (e.g. blow/fill/seal technology for aseptic pharmaceutical packaging)

– Presence of additional isolator technology within the clean room, which may raise or lower the levels of background cleanliness required, depending on the design of the isolator unit.

– Internal quality standards due to localised risk assessment or to gain competitive advantage, for example by claiming higher product purity or reliability.

The issue of localised risk assessment is illustrated by the case of the Hubble Telescope which was reportedly damaged by the presence of a particle of cologne. The resulting cost and effort of repairing the Hubble Telescope while in space was far higher than the costs would have been to prevent the initial contamination.

Apart from any regulatory requirements, facility managers have to weigh up the costs of maintaining a higher grade of cleanroom against the costs of having to repair or replace a contaminated product. This can often be a fine judgement, so it is essential that the standards that are decided upon are enforced and validated: even small drops in quality (increase in contamination) can produce big effects on the bottom line.

Tecomak’s Clean Room Testing and Validation Services
Knowing what standards apply to different classes of clean room, and how to carry out testing in a consistent and reliable way, requires particular expertise and is vital to ensure appropriate levels of cleanliness are maintained. Tecomak are an independent  clean room services contractor, qualified to carry out clean room validation for all classes of facility, meeting all national and industry-specific standards to ensure that not only are your facilities validated and maintained to the required levels, but that your customers and clients can have complete trust in the quality of your clean room processes.

To find out more about how Tecomak Environmental Services can contribute to your quality control processes via our cleanroom validation, testing and maintenance services, follow the link above.