Keep the pressure on
Cleanroom environments often rely on positive pressure to help keep a working environment contamination-free. Nick Davis, director of Technickon Ltd, reviews some of the latest devices that ensure that pressure is effectively monitored and maintained
A cleanroom is a system that consists of very delicate parameters to achieve its cleanliness, it is paramount to ensure these systems operate correctly to ensure products or valuable experiments are not compromised in any way.
Technickon – a new UK-based company established to provide high specification products and systems for the cleanroom and environmental control sector – has developed two systems to ensure cleanroom pressures can be effectively maintained and monitored. These include a door interlock system and a room pressure monitoring system
Door interlocks
Door interlocks are not a new concept in cleanrooms and can be found on almost all cleanrooms built today. The basic operation of a door interlock system is to prevent two doors being simultaneously opened causing instant loss of pressure in the critical rooms. Systems can range from simple two-door interlocking to complex locking sequences and time delay functions on many doors within a facility.
The system can interlock anything from two to 16 or more doors and carry out any type of locking sequence or time delay function required with an on board programmable controller.
Interlock systems are either usually coupled together with components from security systems, or bespoke control panels are built, which can be a costly approach. Technickon’s door interlock system has been designed for the sole purpose of interlocking doors for cleanroom environments with all the possible requirements and variations built into the design.
Good design and easy installation is the key to its success using just one six core signal cable from the control panel to each door location this reduces installation time and therefore saves money. All door locks, proximity switches and additional modules are simply connected into the master traffic light module.
The following are key features of the system:
- Low cost (when compared with a bespoke panel build)
- Override facility and fire alarm control as standard on all systems.
- Bright red/green traffic lights.
- Simple and quick installation and commissioning, further reducing costs.
- Many additional features can be accommodated in the flexible design.
- Latching override feature with alarm to prevent neglected use of the override facility.
- Privacy change feature for under garment change rooms.
Room pressure monitors
The company has developed a complete pressure monitoring system to monitor and record cleanroom pressures accurately. It can design, develop, manufacture, install and validate all types of pressure monitoring systems with any variation of components.
One of the questions often asked is: “How do you know that the tube integrity is intact?” This is a very good question because a small leak in the field tube runs could be pressurised by a plenum with higher pressure than the room, causing unreliable measurements. Technickon has designed a system that can be integrity-tested following installation so that the cleanroom operator can be sure the system is measuring the correct room pressure. The company issues full validation reports for all systems installed and commissioned by us to show compliance with the specification.
Technickon has also built into the design a feature for connecting a manometer without having to remove the tubes from the back of the gauge, this allows easy routine validation and range calibration of the gauges.
The stainless steel room sensor offered by the company has been designed for use in cleanroom areas and is resistant to many aggressive cleaning solutions used today.
The use of barbed connections is another consideration with regards to the installation. Quite often the tube can harden over time and could cause the tube to disconnect when the panel door is opened or from a slight knock. Technickon can supply systems fitted with Sure-Lock fittings that provide a mechanically strong tube connection that will not degrade or weaken over time.
Maintaining room pressure is paramount to maintaining a healthy cleanroom environment, and specification or installation standards for such monitoring systems are sometimes overlooked. The company can provide complete solutions with single point management throughout the design and installation process.
