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” …

Gravimetric Contaminant Testing Flow Chart

As I was writing the recent post about gravimetric Millipore testing it occurred to me that I was trying to boil a good-sized part of a 180+ page document into 500 or so words.  It also occurred to me that many people don’t have the time for or interest in reading endless pages of specifications …

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.  …

Special Edition – Mind Tweezer

Once in a while a question comes up that I can’t think my way through.  Here is one.  Within an insulated system there is air passing over a heat source that constantly produces a certain number of BTU’s per hour.  In the process, the air is heated from the inlet temperature to an elevated temperature …

Thank You!

Thank you to all of you who responded to my plea for insight regarding Millipore testing using particle counting methodology.  Your input has given me some direction and insight into your experiences with this method.  Anyone else who would like to chime in is more than welcome.  Respond in the comments section below or email …

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 …

Welcome Back!

After three + months of sheltering in place, things are slowly returning to the “new normal” here in New York state which is where I write this blog.  We all know all too well what’s been going on around the world over the past several months so I’m not going to belabor those details here.  …

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 …