Dissension can lead to change
By Mike Beavin
“We should be eternally vigilant against attempts to check the expression of opinions that we loathe and believe to be fraught with death.” - Oliver Wendell Holmes
The legendary Supreme Court Justice Oliver Wendell Holmes tells us that the expression of dissent must be preserved or we forfeit our freedom. He also recognized that even the most hallowed documents, including the constitution, were written by mortals and, as such, were not above scrutiny.
Holmes was not advocating lawlessness but the freedom to affect change through speaking out against ideas with which we disagree. If you are a binder technician, there are documents you should be familiar with and abide by. The ASTM and AASHTO standards are essentially laws. You must adhere to them regardless of your opinion of all or parts of them. I’m not insinuating that the published standards carry the same weight as the U.S. Constitution by any means, but the idea is the same. Whether it’s the law of the land or the law of the lab, the documents are binding….unless……unless you work to change the cause of your dissent.
In every Asphalt Institute course, we stress the importance of strictly following the published standards. We remind our students that going rogue and ‘fixing’ a part of a standard we disagree with doesn’t fix anything. It only entrenches a practice that may be contrary to the ‘fix’ by another technician in another facility. In other words, regardless of whether or not you agree with a subsection in one of the standards, you must abide by it or you become part of the problem of testing variability. If you think your opinion is shared by several other technicians, work to fix the issue the right way: by attending meetings and participating in the ASTM and AASHTO processes.
Do I dissent on some issues in the published standards? The answer is YES!
Here are a couple examples:
ASTM D92- Flash and Fire Points by Cleveland Open Cup Tester
Section 11.1.13 When the apparatus has cooled down to a safe handling temperature, less than 60 Celsius (140 Fahrenheit), remove the test cup and clean the test cup and apparatus as recommended by the manufacturer.
This requirement is impractical for many reasons. A typical, properly conducted COC flash test following ASTM D92 takes approximately 30 minutes. We followed the standard as written and recorded a flash point of 314 Celsius. Then, we immediately turned off the apparatus. It took the sample 55 minutes to cool to the ‘safe handling’ temperature. It took another 15 minutes to reheat the cup to a temperature considered unsafe in order to empty it. Section 11.1.13 more than triples the time needed to run the test. Dissent!
AASHTO T 316- Rotational Viscosity
What to do if your rotational viscosity sample and chamber cools too much to allow you to ‘Gently lower the spindle into the asphalt binder…’? Is it permissible to reheat the binder in the viscometer during part of the 30 minute preheat period? If not, how do we handle this? Storing the sample in an oven while waiting for a free RV would be much more damaging to the sample than reheating from a cold state. The standard, as written, does not allow us to cool and store the sample in the chamber, which if properly covered is the same as a sample tin, while awaiting testing. Dissent!
I’ve been grousing about some of the same issues for years. Now I’ve written an article asking binder technicians to adhere to the standards regardless of opinion unless they speak up and get them changed. Looks like I need to do something that many of us ASTM members loathe and believe to be fraught with death: volunteer to help fix the issues the right way.
TECH TIP
Absolutely simple
The glass cleaning oven – life in the binder lab before it was a dark and solvent-filled place with technicians fearful of dirtying a beaker, knowing of the labor, fumes and nitrile gloves needed to make it clean again.
Now? No worries. In go sticky, asphalt coated beakers, viscosity tubes and RTFO bottles and out come shiny, nearly spotless glassware ready to dust off and use. The dark days of cleaning with solvents are gone…right? Not so fast. If you’ve noticed a thin haze forming in the capillary of some of your absolute viscosity tubes after multiple cleanings in the GCO, you’ve probably also noticed that it’s very difficult and sometimes impossible to remove. This is especially true in the smaller capillary tubes. If the capillary isn’t perfectly clean, the friction caused by the film can change the timing of the test and increase variability.
What to do? Unfortunately, the GCO is our friend for beakers, RTFO bottles and many other lab glassware but not for viscosity tubes. Solvent may be the only way to go. But if we have to go there, let’s make it easy and safer.
Clamp the tube upside down over a waste container and place the apparatus in a hot oven for about 15 minutes. Move from the oven to a fume hood, flip the tube upright and immediately fill the tube with a miscible solvent of your choice (citrus works well). Let soak for about 5 minutes and suck the solvent and dissolved binder into a vacuum flask. Repeat as necessary and finish with a rinse of alcohol or acetone.
You’ll need:
• Fume hood
• Vacuum pump
• Vacuum flask
• Hose
• Cork
• Glass tubing
• Ring stand
•
Two-prong clamp
• Waste container
- Mike Beavin, Asphalt Institute Technical Training Coordinator