In order to responsibly use a spray booth, you have to make sure to maintain it properly. One of the most important routines of the maintenance is replacing the filters of the booth, which ensure not only a proper paint job, but also ensure that the outside of the booth is not harmed by an excess of spray paint. To begin with, you need to understand how often you need to replace your filters. 

All spray booths for sale come with pre-installed filters. Most instruction manuals and guides will often mention when these should be replaced, but understand that this largely depends on how often, and for what length at one time, you tend to use the spray booth. For example, if you use the paint booth frequently, and for long periods of time, you will naturally have to replace the filters more often; on the other hand, if you rarely use the paint booth (in which case, it is probably not used for professional services, but for personal use), then you won’t have to replace it often – the recommended frequency is ideal.

The easiest way to identify when to replace your filters is by installing a manometer. This a gauge of how much overspray is present in the filters. The environmental and government bodies of your country or state should have stated a maximum limit for the quality of filtration, which you can identify through this manometer. It is a good idea to install the manometer and calibrate right after you buy your spray booth, because this will allow you to use the new filters (as opposed to buying new spray booth filters later on).  You can read more about this here http://www.mnspraybooths.com.au/product/filters/. 

Following the calibration and installation, your manometer should be showing a reading of zero for your new filters. Most government regulations have a limit of 0.25 or 0.50 for the readings, so mark this limit of your manometer. You should replace the filters when the reading level reaches this mark. There is one other way of gauging whether you need to replace the filters or not. This is the visual method – basically, you try to find any visible differences in the air quality of the paint booth. Of course, this is harder to judge, which is why it is recommended to install a manometer.

However, you should be able to visually judge the air quality as well, because sometimes, you should replace the filter before it hits the mark on the manometer. This may be because the paint job is suffering, or you can generally identify a poorer air quality. Similarly, if the outside is also affected by paint spray, this is another flag to change your filters.