Allied Cleanrooms Blog

Clean rooms are enclosed spaces in which various regulating processes are employed in order to create the conditions for highly sensitive tasks to be carried out. These regulating processes can include HEPA filters, protective clothing, air showers, and rigorous cleaning regimes. The manual cleaning is especially important because it takes care of those particles and other contaminations that have escaped the filters, which in more sensitive contexts, could make a big difference.

Manual cleaning includes a variety of techniques with special materials, such as with wipes. Wipes can be used to clean many surfaces and equipment, and there are sorts of wipes that are more useful and effective than others. Polyester wipes and polyurethane foam make for good wiping materials that won’t shed and contribute to contamination levels. These wipes can be combined with disinfectant to physically contain surfaces and remove additional microbes and bacteria that could remain.

These wipes should also be sterile. Dry wipes are useful when using disinfectant spray for easy to reach surfaces, though for hard to reach surfaces or within equipment, it may be a good idea to use impregnated wipes, but either works fine based on the circumstances.

So with such materials as sterile non-shedding wipes and treated mops and brooms, as well as disinfectants, clean rooms can be contaminant free. Filters get most particulates, but then some always settle onto surfaces and equipment, which is where the manual cleaning comes in. With a variety of effective techniques, a clean room can be a contaminant-free environment for sensitive processes.

While clean rooms maintain a carefully monitored environment free of contaminating particles and humidity, there are nevertheless some things to consider when it comes to dealing with a cleanroom work environment.

Staff should wear full protective coverings such as hoods, specially designed jumpsuits, shoe covers or special boots, and whatever else is necessary to conduct sensitive tasks. Safety goggles or glasses should be used when working with chemicals. Face masks and shields should be used for sensitive processes that could lead to breaking glass or explosions. Always use gloves to handle dangerous chemicals and to prevent shedding skin contamination. Some processes require a respirator, so be sure to have the necessary training and qualification to use those if need be.

Processes in cleanrooms can often involve chemical handling such as possibly hazardous acids, bases, solvents, carcinogens, and cryogenics. Understand the present materials and their use and know the proper procedures of handling and disposing waste. If you come into contact with such a chemical, rinse the area with water for 15 minutes and remove any affected clothing. Hydrofluoric acid can be especially dangerous if eye or skin contact occurs. Such a substance can burn through tissue and even bone which can be very destructive. As stated above, rinse any affected area with water and get medical help.

Chemical processes should be conducted under fume hoods or in wet benches if they pose the risk of spilling. Chemicals should be carefully labeled and stored. All chemicals and mixtures should be properly cleaned and hazardous waste disposed of.

It is useful to know the layout of the cleanroom and to know where the necessary safety equipment is such as safety showers, fire extinguishers, eye wash stations, and emergency shut off switches. It is good to know what emergency signals and alarms indicate, and where to evacuate if necessary. Maintain familiarity with hazardous gas monitoring equipment and any alarms that might indicate hazardous air conditions.

These tips don’t cover everything. Make sure you understand all of the necessary safety precautions and instructions, and make sure the rest of the workers that use a cleanroom and work with processes inside do too. Following some of these basic points will help to eliminate many potential dangers however.

Processes of an environmentally sensitive nature require clean rooms that can keep air contaminants out of the workspace. The manufacturing of microprocessors, the biological research of cultures, and the study of minerals found in space involve extremely sensitive processes that could be ruined by the slightest contamination. Keeping this in mind, workers are required to wear special suits with hoods, gloves, goggles, and masks in order to keep contaminants out of the clean room. They also are required to pass through air showers in order to remove any environmental contaminants. The clean rooms themselves are fitted with powerful filters that keep much of the contaminants out of the room. They can also feature anti-static ion dischargers that can prevent static electricity build up. So it’s pretty apparent that clean room facilities need to be kept free of contaminants.

In addition to all this, workers often employ special cleaning methods and materials to thoroughly clean these clean room facilities to ensure maximum sterility and non-contamination. Below are some examples of these methods and materials.

There are various cleaning liquids and chemicals used to clean countertops and things of that nature, such as distilled water and isopropyl alcohol. There are also brooms used with special polypropylene-coated heads that can be used to clean up floors; these heads will not build up bacteria that could contaminate the clean room. Special mops are used as well, such as sticky head mops, which can come in the form of flat heads or rollers, which can pick up particles to be removed from the clean room. Sponge mops and non-woven mops can also be used to absorb particles and liquids during clean up.

Other sorts of rollers can be used to clean equipment and counter tops along with special wipers that can clean up particles and liquids without breaking up and producing more contamination. Squeegees can also be used for liquids. Though clean room filters can remove much of the air particulates, workers and scientists can often track more materials into the room, which can settle on equipment and counters, making it more difficult to remove with air filtration alone. And there can be spills that need to be cleaned as well.

Workers who pose the danger of tracking in particles with their shoes can use shoe cleaners that function like golf shoe cleaners, or they can put shoe coverings on before entering the clean room in order to ensure even more cleanliness.

Finally, special industrial strength vacuum cleaners can be used for whatever particles escape the cleaning process. These vacuum cleaners are especially engineered to avoid dumping exhaust, so that the process is as clean as possible. All of these techniques serve to keep clean rooms as clean as possible.

Cleaning CleanroomsAccording to industry cleaners, possibly a quarter of cleanrooms maintain a serious and thorough cleaning schedule for their cleanrooms, which leaves a almost three quarters of clean rooms open to contamination, possibly necessitating the replacement of filters, vents, equipment, or a reworking of the clean room itself, which could lead to costly downtime.

Clean rooms are designed to keep contaminating particles and microbes out of the workspace. They are sealed rooms that often feature HEPA filtering systems of various types that remove particles in the air. Staff are generally required to wear protective clothing, hoods, and goggles to prevent additional shedding and the tracking in of particles from outside.

But again, the key aspect of the filter process is that the system removes particles from the air. When these particles settle onto surfaces they are more difficult to remove and can lead to contamination of sensitive processes in the room. Protective clothing and air showers can remove a lot of contaminating matter, but particles can often be dragged inside regardless. That is why it is important to maintain a regular cleaning regime in the clean room.

Clean room cleaning often involves specialized materials such as treated brooms, mops, and rags that are either coated or non-shedding or both. They also involve heavy duty cleaning agents that should remove as much contamination as possible so that the filters can do the rest of the work.

Otherwise it can be very expensive to replace contaminated equipment, and the downtime generated by a lapse in work could be equally costly, not to mention compounding problems caused by stalled supply chains if involved. If you are running a complex operation, one inactive clean room environment could have major repercussions for your entire operation. So considering the costs involved with downtime and contamination, it really isn’t too expensive or troublesome to maintain a rigorous cleaning schedule for your clean room.

The air around us can contain trillions of particles per cubic meter. Clean rooms on the other hand contain from 10,000 to 1 particle per cubic meter in the air. They achieve this with their special filtration systems, special suits for workers, air showers, shoe cleaners, and daily cleaning of surfaces and objects. Clean rooms show us how particles that are floating around in the air can easily settle onto various objects and surfaces, where they can be transferred all over the place. In the case of clean rooms, that would be the components and processes that shouldn’t be contaminated. So if one is careful enough, and the clean room is doing its job, sterility and non-contamination can be achieved.

Where do all of these contaminations come from? They come from numerous places: they can be tracked in by workers; they come in through unfiltered ventilation systems, and most of all, humans themselves. Humans shed 1 billion skin cells a day, which can carry bacteria. So clean rooms get rid of a lot of these particles with filtration systems; the rest of the particles can settle onto surfaces however, which have to be cleaned up with special products.

That is why it is a good idea to constantly clean flat surfaces, even in your every day environments, where particles can settle from the air and build up. Bacteria can build up in these areas, leading to unclean conditions and the transmission of flues and colds. Even if you don’t have a high quality filtration system, you can still keep your regular workspace (or your house) clean by ensuring that surfaces are constantly clean, since particles are always settling on them.

Particles themselves that are wiped up should be disposed of without touching the clean surfaces with the soiled cleaning materials, which could lead to recontamination. You may not be able to achieve the low particle count that a clean room can achieve, but at least you can remove a lot of particles that could potentially contain bacteria, which will guarantee cleanliness and better health in your workspace or residence.

Sensitive processes like scientific and pharmaceutical research, microprocessor manufacturing, and culture development require sensitive environments. Critical environments, also called clean rooms, can provide for those environments, but they have to be designed very carefully to carry out such technical functions. Clean rooms are complex and can be costly, so they have to be done right. Below are 10 aspects of that design process that could be considered.

  1. Clean room designs should take into the account of staff and material movement. That means critical processes such as pharmaceutical production should be isolated from major pathways in the layout. These processes should have single access and be out of the major pathways to prevent cross contamination.
  2. Clean room classifications are important and will determine the overall design and requirements of the clean room. The more sensitive the processes you need to administrate, the more stringent standards required for clean room cleanliness. Classes range from 1 to 100,000, with the lower numbers indicated higher standards in particle removal. For example, a class 100 clean room requires 3,500 particles/cu ft or less at 0.1 microns and larger, 750 particles/cu ft or less at 0.2 microns and larger, 300 particles/cu ft or less at 0.3 microns and larger, 100 particles/cu ft or less at 0.5 microns and larger, and 24 particles/cu ft or less at 1.0 microns and larger. At higher classes, the requirements are lower, at lower numbered classes, the requirements are higher. Knowing the sensitivity of your project and how it corresponds to the clean room class requirements is important in designing a critical environment.
  3. Space supply airflow figures in terms of the clean room’s class of cleanliness and the amount of traffic and particles that will be coming in through the room. A higher value indicates a higher trafficked area and should be considered when designing a clean room.
  4. What sort of space pressurization will your clean room use? Positive pressure is useful for pushing air out of the room and keeping the contamination out. It pays to think about pressure differentials between rooms as well, as a certain differential will not only have consequences on cross contamination, but energy used to maintain pressures and the difficulty of opening and closing doors.
  5. Space exfiltration flow has to do with air moving from room to room when doors are opened between rooms of various pressure differentials. Which direction is this air moving? Which direction should it move? A good clean room design should have carefully controlled air flow.
  6. Space air balance has to do with the overall movement of air between rooms that takes into account present air, air leaving, and air coming into the rooms. This variable plays a role in the way clean rooms are designed as well.
  7. HVAC systems can be used to manage temperature and humidity. Unless a clean room process requires a higher temperature, a lower room temperature should be planned on to account for present staff and their warm clothing (full coveralls, hoods, goggles, masks, and gloves). Humidity on the other hand should kept to a certain degree where particles aren’t kept stuck to surfaces due to higher electrostatic discharge, but not too high where microbes/bacteria can thrive. HEPA filters with laminar air flows can take care of particles as well.
  8. Mechanical system layout figures into the cleanroom design. This aspect can be affected by such variables as space availability, available funds, project requirements, classification level, energy, building codes, and local climate.
  9. Heating and cooling calculations for the clean room take into account the following considerations: required climate, air movement, humidifier manifold heat, process load, and recirculation fan heat.
  10. Finally, how much space will be needed for the mechanical systems that will keep the clean room clean? What sort of classification of clean room will be built and how clean must it be? The design may have to make room for machinery depending to needs: filters, heating/cooling coils, fans, sound attenuators, return fan, relief air section, outside air intake, humidifiers, discharge plenums, and more. As you can see, clean rooms are quite complex and require much deliberation in design.