Tape Test for Cleaning Revisited

In a very early blog written in 2011 I talked about the “Scotch” tape test for cleanliness.  At that time I did not address quantification of the results other than as a visual assessment.  In addition to evaluating general cleanliness, this technique is being found particularly applicable when determining the cleanliness of substrates that “shed” …

Millipore Testing – Gravimetric

Millipore testing is all about evaluating cleanliness based on the presence of particles or other solid, non-soluble contaminants.  In general, it can not be used to detect the presence of hydrocarbons or other contaminants which will be solubilized in the extraction process.  The results of Millipore testing are generally expressed by weight using gravimetric analysis …

Millipore Specifications Update – Extraction and Sample Preparation

“Millipore” testing evaluates cleanliness by extracting particulate contamination from a surface and then either weighing or counting and quantifying the collected particles to assess the cleanliness achieved by a prior cleaning means.  The first step in either case is to collect and prepare for analysis any particulate residue remaining on the surface after pervious cleaning.  …

Foil Test – Foil Variabilities

It would make sense that variations in the aluminum foil used for testing in the foil test for ultrasonic performance could have a bearing on the outcome of the test.  Most people use standard “grocery store” aluminum foil for testing because it is inexpensive and widely available.  So let’s talk about that first.  The most …

Millipore Testing – Help!

I just spent a couple of hours re-reading several of the ISO specifications related to “Millipore” testing including ISO16232-3 and -7.   I put the word Millipore in quotes here because although these are normally called Millipore specifications, none of them mentions the word Millipore.  (Millipore happens to be the name of a company that developed …

Aluminum Foil Test for Ultrasonic Performance – Potential Problems

Task At Hand – In a previous blog I declared that I am not a fan of the aluminum foil test for evaluating ultrasonic performance.  I question its validity and relevance on a number of fronts.  If my purpose here is to question my own skepticism, then I guess I should probably define the factors …

Aluminum Foil Test – Foil Perforation Mechanism

Until recently, I was only able to theorize about the mechanism involved in the perforation of aluminum foil by ultrasonic cavitation.  I no longer have to theorize! My theory had always been that perforation of aluminum foil was due to the repeated flexing of aluminum foil as cavitation implosions occurring on opposite sides of the foil …

Aluminum Foil Test

If you’ve heard of ultrasonic cleaning you’ve probably heard of the aluminum foil test.  The practice of putting a piece of aluminum foil into an ultrasonically activated tank of water probably began as a novelty demonstration.  The holes produced in the aluminum foil by the collapse of cavitation bubbles at least showed that something interesting …

How Much Chemistry – Liquid

Using the right amount of chemistry is important to successful industrial cleaning.  Since there is no standard convention for expressing the amount of chemistry to use, it sometimes takes a little effort to sort things out.  Chemistry is supplied in either liquid or powder form with several different conventions for each.  Let’s look at liquids …