A lot of people understand what a cleanroom is but when you get to the component level, one of the factors that is underestimated is the importance of a good air shower. Some clean rooms you can simply enter, gown up, and then go your way, but this is not optimal. A good air shower helps to minimize the contaminants coming into your environment and help to ensure that your company is producing the best, most contaminant free products as possible. In today’s article we will discuss the importance of the cleanroom air shower and show you a good example should you find our arguments convincing. Without further ado, let’s discuss the unsung hero of the cleanroom, the air shower!
Looking clean doesn’t mean that someone is clean
The biggest source of cleanroom contamination is, of course, going to be the people working in it. While putting on a gown is a good first step, the process of changing clothes is going to disturb particles that have been brought into the clean room and you can’t expect the air filters to immediately catch all of it. In all likelihood, these contaminants are going to shake off of the clothes, spend a bit of time airborne, and something is going to end up on that cleanroom gown. This is where an air shower is the solution that you need.
So what exactly is an air shower?
An air shower is an enclosed air recirculation system that uses high velocity jets of air in order to ensure that after an employee has put on their cleanroom clothing that they are further decontaminated before entering a production cleanroom. The jets of air catch particles that would have normally been missed and while an air shower costs you in the beginning it can save you money in the long run (which we will detail further later in this article).
How do they work?
Think of it as rather like an airlock in a science fiction movie. An employee suits up, enters into the cleanroom air shower and then the doors magnetically seal. This is followed by a period of 4 to 8 seconds where this person is then inundated with filtered air as they raise and lower their arms in order to maximize the cleaning efficiency. An assortment of slits or nozzles within the air shower work their magic and then take a few seconds to wind down, at which point the employee exits through a different egress point leading straight into the clean room proper. The filtration within these units is HEPA grade, meaning that they are intended to remove 99.97% (.3 microns) worth of contaminants. This should ensure that they are coming into your clean room CLEAN.
What are the benefits of this process?
The benefits of this process are exceptional. By ensuring that a second step beyond simply changing clothes is observed you achieve the following:
- Decrease cleanroom maintenance – While it may not seem much until you give it a little thought, contaminants are going to build up over time, even with the best of filtration systems. By introducing an air shower into the process you can dramatically decrease that process of buildup, leading to less maintenance being required overall. Air showers help to keep the cleanroom as pristine as possible.
- Reduce energy consumption – With less contaminants being introduced into your cleanroom, your filters are not going to be having to work as hard. This leads to savings and every penny counts. Air showers help to ensure that you are not wasting money.
- Increase the lifespan of your filters – Without an air shower those air filters are working hard and aside from the energy considerations we mentioned before, HEPA filters do get buildup during the process of trapping contaminants. Air showers can increase their lifespan and whether you are running a large or small array of HEPA filters you want them to last as long as possible.
- Improve overall production – Your products need to be as contaminant free as possible, during the fabricating, testing, and packaging process. By utilizing an air shower and dramatically reducing the contaminants then you are going to have an improvement in your product yield as less of it will be marked as contaminated.
Now that we have established the benefits, let’s take a look at a popular air shower from Terra Universal.
Terra Universal Cleanroom Air Showers
Here is a great example of an efficient air shower. Per Terra, the HEPA filter in this unit is rated at a staggering 99.99% efficiency. LED lighting within the unit makes sure that it is well lit at a fraction of the
cost of other lighting and once entered the unit beings the shower process through the medium of a motion sensor. The magnetic interlock system ensures that upon entry the subject will be not be leaving until the decontamination process has been completed, except in the case of a power outage where the entry door will automatically disengage and allow the exit of the air shower. There is also an emergency exit button that may be pressed at any time to terminate the shower process should an exit be required. Shower time within these units may be customized by the means of the control panel and the Photohelic gauge within these units detects when HEPA filtration is becoming clogged and inefficient, creating an alert that the filter needs to be changed. All an all, it’s quite efficient.
Some final words
In this article we have discussed the importance of the air shower to your cleanroom envionrment, along with how it works and an example of this technology used in many production environments today. Remember, the cleaner your cleanroom, the less you will pay in energy costs, filter replacement costs, and contaminated yield costs. When you really think about it, an air shower practically pays for itself. So add an extra step to the cleaning process when entering the cleanroom, it’s worth it!