The Considerations of Building a CleanroomRyan White
An integral part of scientific research, yield optimisation, safety assurance and quality control, cleanroom installation is increasingly important within the manufacturing process.
Whatever the cleanroom is being used for, their potential for hazard means that its design requires the utmost care and attention from both the respective departments using it and the design team. Here, we’ll detail the biggest considerations to take into account when designing and building a cleanroom.
Types of Cleanroom
Two major types of cleanroom have evolved, differentiated by their method of ventilation:
Turbulently Ventilated Cleanroom
In this kind of cleanroom, the room receives clean filtered air through air diffusers in the ceiling, which then mixes with the room air, before the airborne contamination – generated by people and machinery – is removed by air extracts at the bottom of the walls.
Unidirectional Flow Cleanroom
In a cleanroom of this design, high-efficiency filters are installed across an entire ceiling, or the wall, supplying the room with air. Swept across the room in a unidirectional manner, it exits through the floor, removing the airborne contamination from the room.
Both types of room use clean air devices, such as unidirectional benches or isolators, that help to supply filtered air in localised areas where it’s needed – for example, at the area where the workflow is most open to contamination.
When designing a cleanroom, it’s important to take into account the amount of space its mechanical equipment takes up. In the design stages, keep flexibility in mind, as this helps with issues of expansion and modification further down the line, as well as the addition of new equipment and tools.
Additionally, a flexible cleanroom design means a quicker change-over of equipment, resulting in increased productivity, reduced cost and a minimal risk of contamination in the long term. When it comes to flexibility, there are several design elements you can employ to help make a cleanroom more agile.
Wall chases can be used to house superfluous ductwork, electrical utilities and process work within them, while bulkheads permit the transfer of equipment or pharmaceuticals between a cleanroom’s walls without risking spillages or breakages. Likewise, struts can be used to free up much-needed floor space.
Since there can be a lot of dust, dirt particles, harmful chemicals and other contaminants in these kinds of protected environments, airlocks can help minimise or prevent any changes in pressure that may compromise the workflow.
During the day-to-day use of a cleanroom, even something as innocuous as a person walking across the room, can create turbo-electric charges, which may inadvertently affect or damage certain things present in the room. The correct packaging can be used to prevent static damage and implement the proper grounding.
Consider replacing the insulating materials where possible and install ionisation technology if needed – it’s important to have cleanroom managers conduct a static audit in order to identify potential problems and what might be causing them.
Temperature and Humidity
These two factors integral to the design and function of a cleanroom, and temperature control is necessary to a cleanroom as it helps provide the correct conditions needed for materials and instruments. Meanwhile, the control of humidity is needed to prevent corrosion, stop work surface condensation, and reduce static electricity.
Perhaps most importantly, both of these controls are integral to the personnel’s comfort, so it’s particularly critical that a balance is struck to ensure optimum workplace conditions for lab staff as well as the materials your cleanroom will be housing.
Your cleanroom should be maintained at a static pressure higher than atmospheric pressure in order to prevent infiltration by the wind. Additionally, the air pressure should be set up in a way so the air moves from clean to the less-clean areas.
One exception to the positive differential pressure rule: governmental agencies require the room to be at a negative pressure when dealing with certain hazardous materials.
High-Efficiency Particulate Air Filters
Practically a necessity when it comes to cleanroom design, these filters are essential to controlling contamination since they filter incredibly small particles with a 99.7% minimum particle-collective efficiency. Whichever room design you choose to use, HEPA filters are essential.
If your lab team is looking to install a cleanroom for its processes, the team at InterFocus can help. For more information about our bespoke fitted labs, visit our homepage or call the team on 01223 894 833.