Hi everyone,
Need some advice here. next week my company will have an audit on FSSC 22000. I would like to ask regarding air compressor , is it consider non conformance if we didn't install a filter at the point of use to control the compressed air quality. for your information we only use the air compressor for machine cleaning purpose and in the pneumatic machine. One more question, is it ok to have reading on oil contaminant in the compressed air since our air compressor oil is food grade?
Someone please help me ![:helpplease:](https://www.ifsqn.com/forum/public/style_emoticons/default/helpsmilie.gif)
The food grade food grade oil is only an element in the compressed air process for the food industry. In compressed air, the main vector is water. Associated with water are aerosols, vapors and odors and particles. Eliminating particles is the easiest process. Three-dimensional borosilicate micro-fiber construction filters, commonly used in compressed air filtration and called coalescing filters, remove solid particles with high efficiency at efficiencies that can reach 99.9999% relative to the pore diameter: 1 micron ; 0.1 micro, 0.01 micro (most common). It is understood that the more pollution there is (pollution in the environment) the greater the loss of load in the compressed air system. Water and oil (hydrocarbon) vapors, depends on many factors: the first is the ambient temperature and the concentration of humidity in the air (RH). As an example: if you are in a region with very high ambient temperature and this environment carries a high H.R., the filters will remove a small part. We must not forget that all equipment and certifications of compressed air equipment and their performances are referred to 20 / 21ºC. Its efficiency at 30 or 40ºC will be absolutely distinct. Much worse. This is where the compressed air dryers come in. In a basic installation, for the general industry without a specific purpose, the dew point under pressure (pdp) of 3 ° C (37 ° F) is commonly accepted. In order to obtain this dew point, it is usually used the refrigerating dryers, which cheaply removes a large percentage of water. However, by measuring the amount of water vapor contained after this thermal shock, through a hygrometer suitable for quantifying the amount of water vapor present, we reach about 7,500 ppm (v) at the standard pressure of 7 bar. As has already been proven and with numerous international publications on the subject, it is concluded that for the development of microorganisms in the air at this pressure (7bar), it is necessary that the air reaches at least the pdp of -26ºC, so that such microorganisms, become spores and then removed as particles. There is only one feasible and safe process for drying compressed air for the food industry: it is using adsorption dryers with molecular sieves based on alumina, zeolite or silica gel. The most widely used in the food, pharmaceutical and hospital industries is active alumina. With these dryers known as desiccant dryers, the pdp of -40 is easily reached. The water vapor content measured by the same process is reduced to about 130 ppm. So if you now have dehydrated air with this value (or better) activated carbon and particle filters work flawlessly. And here we speak in the oil of the food grade class: this oil does not stop being a fossil oil. Its function is to prevent accidents that do not contaminate food in such a way that they are unfit for consumption. But we must not forget that with humid air (and with pdp 3ºC the air still has 7,500 ppm (v) of water vapor) the air has the optimal conditions to develop microorganisms. Therefore it can not in itself be suitable for applications in direct contact with food, or without contact but at risk. Here we come to the recommendation of the BCAS that decidedly recommends pdp -40ºC, oil elimination 0.01 mg / m3 and less than 400,000 particles in accordance with the stipulated by ISO 8.573: 2010, which then raises the standard for class 1 in hydrocarbon (0.01 mg / m3) Class 2 for water vapor pdp -40ºC and suspended solids class 1 or 2). A lot would be said about this, namely oil-free compressors vs lubricated compressors, but it stays for another occasion. Do not forget, to stop the development of microorganisms in the air it is necessary to reach at least the pdp of -26ºC. This is my fight.