Cleanroom Compatibility of Chemtronics Products
From time to time, we get inquiries in Technical Support, asking if a particular Chemtronics product is cleanroom grade or cleanroom compatible. Usually this question arises with regard to our duster products, but sometimes also involves our static dissipative products and aerosol solvent cleaners. There is no simple answer to this question. It all depends on the standards the cleanroom user is trying to maintain in his cleanroom operations.
Can Aerosol Duster Be Used In a Cleanroom?
Chemtronics duster products contain either 100% HFC-134a, HFC-152a, or the latest environmentally friendly HFO-1234ze. These are all completely volatile compounds that are gas at room temperature, and which have been filtered to remove all particulates 0.2 microns or larger. So these product are inherently cleanroom compatible for Class M1 cleanrooms (ISO Class 2).
However, these products are not packaged in a cleanroom environment, nor is the product packaging design associated with the term “cleanroom”. For example, a truly cleanroom compatible product would need to be “double bagged”, or packaged in such a manner so as to prevent introduction of particulate contaminants into the cleanroom.
Chemtronics does not typically promote using a duster product in a cleanroom environment. Even though the duster itself may not add any additional burden of particulates to the air in the cleanroom, use of the duster may scatter particulates that were previously not airborne and therefore not detected. The increase in particle count might not be noticeable in a Class M4 or higher cleanroom, but would probably be detectable and unacceptable in a Class M3.5 or lower environment. The use of duster products should be the decision of the cleanroom operators, who determine the particulate standards they need to operate.
Dusters are extremely useful and important products, effective in removing dust from electrical components in the field, in so-called “controlled environments, and in Class M6, Class M5 or even Class M4 environments. However, they are not necessarily proper for use in a “classical” cleanroom, or environments controlled to less than Class M4 cleanliness.
What Is the Alternative to Dusters In a Cleanroom?
Instead of scattering particulates inside the cleanroom with dusters, particulate contamination is usually collected and removed using solvent-saturated wipes and swabs. Chemtronics holds a position different from other aerosol product manufacturers, because Chemtronics supplies Coventry™ cleanroom products to the operators of critical cleanroom environments. Coventry cleanroom swabs and wipes are manufactured under cleanroom conditions. The manner in which these products have been manufactured and packaged, as well as the materials used in their construction and packaging, have been chosen and processed to insure the lowest particulate count possible.
Can ESD Products Be Used In a Cleanroom?
ESD products, such as the Static Free™ Mat and Benchtop Reconditioner, which deposits a volatile static-dissipating film, could be considered unacceptable in critical environments. This is due to the inherent increase in particle count, resulting from volatilization of the solvents they contain. We recommend using such products only in Class M4.5 or higher cleanrooms.
Can Solvent Aerosol Cleaners Be Used In a Cleanroom?
The droplets of liquid produced when any solvent-based aerosol product is sprayed, usually precludes its use in cleanrooms below Class M4. This would include all of the Chemtronics Electro-Wash® Cleaners, Flux-Off® flux removers and Pow-R-Wash™ contact cleaners. Also aerosol coating sprays, such as Konform® conformal coating products are usually not recommended for use in Class M3.5 or lower environments.
Even after the solvents and propellants evaporate, finely atomized particles of the coating will add to the particle burden in the cleanroom. Again use of such products in the cleanroom environment should be left up to the cleanroom operator.
The same recommendation applies for the all the solvent-based CircuitWorks® products, like the Conductive Pen, Conductive Epoxy, Overcoat pens, Flux Dispensing pens, and Flux Remover pens. These products give off volatile chemical vapors as they cure.
For more information on the best cleaning methods of all types of cleanrooms, contact your Chemtronics application specialist at chemtronics@itw-cc.com.
