Clean rooms are sealed spaces that are engineered to reduce particulate matter in the air to almost zero and precisely control temperature and humidity. They are absolutely vital in a number of industries:
- High technology, where clean rooms are used in microprocessor manufacturing.
- Pharmacology manufacture, where chemical compounds must be brewed under precise conditions and without contaminants.
- Disease research, where potential infection vectors must be controlled.
- Space industry, where spacecraft must avoid taking terrestrial viruses or bacteria off-planet.
For chip manufacturers such as Intel, for example, a single particle of dust can utterly ruin an entire manufacturing run of microprocessors by settling on the die or individual wafers. With functional elements much smaller than the particle, circuits would be shorted or never connected, and thousands of dollars worth of work would be rendered worthless.
In pharmaceuticals, the stakes are even higher—contamination during either manufacture or research can lead to bad results that cost lives. A colony of bacteria that thrives at a certain humidity level can completely wipe out another culture that biologists are attempting to grow.
Clean Room HVAC Technicians Meet High Standards For Air Quality
No clean room is 100 percent free of contamination. Part of the role of HVAC technicians is to keep the levels of particulate matter, humidity, and heat within specified ranges as determined by what the room is used for.
In the United States, standards for these conditions are set by the General Services Administration.
As of the 2001, the code specified is ISO (International Standard for Organization) 14644 Cleanrooms and associated controlled environments. The standard has seven parts, specifying everything from varying classification levels of cleanliness to the testing methods that must be used for compliance.
There are nine classes, each with different ranges for the number of allowed particles in certain size classes. Different industries and applications will call for different class standards.
HVAC technicians ensure that the clean room maintains an environment that conforms to that class with a number of different techniques.
Balancing Filtration and Air Flow Rates Requires Experience
Filtering is the primary method for keeping particles out. Air scrubber systems used in clean rooms typically take a combination of HEPA (High Efficiency Particulate Air) filters through which outside air is passed to pull out particles. For very stringent classes, special ULPA (Ultra Low Particulate Air) filters are used.
The heavy filtering introduces special concerns around pressure, since air can only be pushed through dense filters at a certain rate. Clean rooms are typically over-pressured compared to the outside environment, to force air out of any gaps or temporary openings rather than allowing contaminated outside air to flow in.
Air flow itself is also a tool that helps keep rooms clean. Air curtains may be used across openings into clean rooms to wash off and blow away potential contaminants. Laminar flow systems are maintained to direct filtered air across ceilings and down through the work spaces.
Technicians Follow Special Protocols and Procedures to Maintain Standards
All this takes attention to detail when it comes to HVAC system design and operation; a level of attention several steps above typical commercial HVAC work.
HVAC technicians in clean room environments also have to comply with special protocols to keep from introducing contamination into the system themselves. Special clothing and protocols have to be used any time the room is entered to perform maintenance work. Gloves, booties, aprons, and jumpsuits are some of the minimum dress standards for working in clean rooms—and if you have a beard, get ready to stuff it into a cover before you go in, because there’s a lot of stuff living in there that clean rooms won’t like.
There are detailed procedures for getting into that clothing as well, to ensure the outer surfaces are not contaminated before entering the room. Your tools may have to be sanitized and perhaps stored in the clean room itself rather than risk contamination by carrying them in and out.
Of course, much of the HVAC system will be housed outside the clean environment. Clean room HVAC mechanics can expect to spend some time out on the roof, working on compressor and fan units, just like any other HVAC worker.
Careful cataloging of maintenance operations and filter lifespan has to be performed to keep the system in operation. This attention to detail is a hallmark of clean room HVAC mechanics, who cannot overlook a single possible source of contamination or failure.
How To Become An HVAC Clean Room Technician
Clean room technicians are usually part of the facilities maintenance staff at the organizations that employ them, and it’s possible to work your way into those jobs by starting off in general maintenance. For many, despite the critical nature of the work, clean room HVAC maintenance is only one part of a larger job.
The job descriptions tend to vary from company to company, but having electrical and plumbing knowledge in addition to HVAC skills is a common requirement. Clean room HVAC techs might also work on other facility HVAC systems, or may have responsibilities for maintaining air flow systems in secure glove boxes or biological safety cabinets used to store toxic or infectious substances.
Some clean room technicians also work for HVAC contractors who service or build such facilities.
Depending on the state and locale of the position, you may or may not need a dedicated HVAC mechanics license to work on clean room facilities. Licenses usually have some combination of requirements for formal classroom education and on-the-job experience. A dedicated HVAC certificate program or associate’s degree is excellent preparation for such jobs and will often at least partially satisfy the education requirements for licenses.
Apprenticeship opportunities do not usually exist for clean room positions except with respect to facilities that hire union facilities maintenance staff. An apprenticeship with an operating engineers union may involve up to five years of combined on-the-job training with classroom education, but competition for such positions is fierce.
One of the best ways to prepare for a career as a clean room HVAC technician is by obtaining a speciality certification in the field. There are two major certification standards, both of which share a significant drawback: you must be employed by a certified company in order to obtain the individual certification.
One of these is the NEBB Certified Technician (CT) credential from the National Environmental Balancing Board. Technicians who work for NEBB certified companies are eligible for the credential and can receive additional specialized clean room performance testing for the more advanced Certified Professional (CP) credential.
The Associated Air Balance Council has a Cleanroom Certification Engineer credential, available to agencies of AABC certified member agencies. The CCE is an advanced certificate, only available to candidates who already have a Test and Balance Engineer or Test and Balance Technician certificate through the council.