In Life Sciences, GMP aspects of product contact, process functionality and capacity often determine the design of equipment, utilities, facilities and cleanrooms. Hygienic Design of the exterior aspects of equipment is often neglected.
Cleanrooms and utilities are cleaned and sanitised or disinfected relatively easy with a wide range of standard solutions available. Equipment exterior, however, that is a different story. Its cleanability is often left to the manufacturer to consider and, usually, both the end-user and the manufacturer focus primarily on functionality and process cleanliness.
What is often forgotten, is that the equipment is stationed in a classified cleanroom and that the physical design and materialisation choices of parts like control cabinets, printers, motors, and insulation have a big impact on the air cleanliness and bioburden of the cleanroom.
Validation issues at the final stages of facility acceptance could be the result of the improper hygienic implementation of equipment in cleanroom environments. In many cases, the Hygienic Design of the equipment exterior is insufficiently addressed in the equipment’s specification. When issues regarding cleaning and disinfection are identified later during the installation and qualification phases the remediation will result in delays and rework and thus substantial additional costs. Addressing it at an earlier stage can prevent this from happening.
Hygienic Design issues related to equipment exterior can be minimized keeping the following possible root causes in mind when you are writing a specification for new equipment:
Equipment supplier has limited or no experience with production scale equipment
Particularly in Research and Development situations, new production developments or production upscaling situations where new types of equipment are used and technologies for large-scale production are not readily available and must be developed specifically.
Scaling of equipment (standard piping/ fully custom)
Another reason that hygienic design of equipment exterior could be impacted negatively are the design decisions made by the supplier during scale-up of the equipment. For example, different solutions for process piping, connections, parts, and electrical cabling might be needed during the scale-up process. In the development phase, disposable tubing with couplings could be used while a production scale might require a different approach. E.g. the limited experience by the supplier can lead to the selection of standard piping with couplings where fixed piping with full welding documentation would minimize the use of couplings and ability to clean the inside and outside of the equipment. Another solution could be to keep the full process path fully disposable
Limited experience with installation in a cleanroom environment
A Research and Development environment usually has different requirements than a production department when it comes to cleaning of the outside of the equipment and particle generation. A supplier that is not used to deliver equipment for use in a GMP cleanroom environment might select solutions that are well accepted in the development phase but not in a regulated manufacturing environment.
Additional, special requirements (e.g. ATEX)
Implementation of additional requirements, special non-standard requirements can impose a risk on the hygienic design of your equipment. Examples of these additional special requirements are ATEX requirements. It is important that the introduction of non-standard solutions are submitted to a proper assessment of possible alternatives and impact on the ability to clean the equipment.
Changes in the design requirements
Some may say that a project without changes isn’t a real project. True, but changes after the specification phase impose a risk, especially when changes aren’t assessed integrally, resulting in solutions that are only assessed on functionality. When changes are required, they should be assessed against the initial starting points and this assessment should be performed by the original design team. In addition, a proper change procedure can help to address this problem.
Solutions for these pitfalls:
For most potential pitfalls, there are simple solutions.
- The simplest and most effective solution is ‘being aware’ of these pitfalls and the fact that external hygienic design of your equipment definitely impacts your cleanroom.
- Ask for reference projects and assess solutions before placing the order.
- During the construction phase, request not just drawings, but also pictures or even better visit the manufacturing site.
- Assess non-standard solutions before prior to implementation.
- Look for options to avoid the installation of difficult to clean equipment in your cleanroom. E.g. locate the difficult-to-clean equipment outside the cleanroom and only have your process connection in the classified area.
- Finally, start as soon as possible. If the hygienic design is impacted, a solution should be found to mitigate the impact. The best moment to do this is during the design phase instead of doing this after installation and qualification.
It might sound simple, but is it really? Not always.
Sometimes things become difficult and complex because you get tangled up during the process and your vision gets blurred. So it’s wise to take some time to reflect on the matter and clear your head.
As Steve Jobs once said: “Simple can be harder than complex: You have to work hard to get your thinking clean to make it simple.”
Blog by: Gerco van Veen