John DeLaHunt's correspondence with the author of the article I  
passed along yesterday...

- Ralph


From: JDelahunt**At_Symbol_Here**ColoradoCollege.edu
Subject: RE: College's workers apparently transporting chemicals  
without being told proper procedures
Date: Tue, 27 Feb 2007 21:26:07 -0700

Curious to me that the writer compared 25 grams (<1 ounce) of moist  
picric with the Halifax explosion, which was ton quantities of high  
explosives.

http://en.wikipedia.org/wiki/Halifax_explosion


John
jdelahunt**At_Symbol_Here**coloradocollege.edu

________________________________

From: Angela Woodall [mailto:awoodall**At_Symbol_Here**angnewspapers.com]
Sent: Tue 2/27/2007 11:29 PM

Thank you for your e-mail.

I am not sure what the nature of your comment was. But just to assure  
you of my intentions I will say that the site you copied in your e- 
mail is one of the many that I used to gather info about picric acid.

In addition, I was not comparing 25 g of the acid to the Halifax  
incident. Rather, the explosion was used to illustrate the explosive  
nature of the acid. Whether it was as dangerous, the janitor who  
handled it seemed stunned by the connection. That's human nature.

In addition, if the quantity were harmless, would the Hazmat unit of  
the Fremont Fire Dept. have called in the bomb squad? Maybe it was a  
precaution, but the point was that individuals with no knowledge,  
equipment or training to handle hazardous materials were doing so.  
The college clearly needed to update its procedures, as the concern  
voiced to me (and the investigation) by OSHA illustrates.

Thanks again for your feedback.
Best,

________________________

From: JDelahunt**At_Symbol_Here**ColoradoCollege.edu
Date: Tue, 27 Feb 2007 21:26:07 -0700

Ms. Woodall;

The nature of my comment was criticism about the connection between  
the Halifax explosion and 25 grams of moist picric acid.  Even if the  
materials are similar, the scale must register with even the least  
scientific of observers.

Ohlone:  25 grams (0.000025 tons) picric acid
Halifax:   1,602,519 kilograms (1,602.5 tons) wet picric acid, 544,311
(544 tons) kilograms dry picric acid

Taking all the Halifax picric acid together, there was about 85  
MILLION times more mass on the Halifax than in the Ohlone case.  Your  
article doesn't mention that, and the omission makes the Ohlene case  
appear worse than it was, simply by inference, even if we agree that  
you did not intend a comparison.

At no point did I state or infer that picric acid is "harmless."   
Your assumption that I take that posture is unwelcome and unsupported.

However, since you've had the courtesy to respond, let me air some  
other concerns about your presentation of the story:

"Volatile" is a poor word choice.  As a term of art in chemistry,  
"volatile" means "capable of evaporating rapidly."  I appreciate that  
Roget considers "explosive" and "volatile" to be synonymous in the  
vernacular, but I believe the latter in this case would better refer  
to "a volatile temper."

Only dry picric acid is unstable, and then generally only when in  
contact with transition metals - the Wikipedia article on the Halifax  
explosion mentions this.  It is routine among chemists to simply  
invert a container of picric (with a plastic lid, a detail your  
coverage of the Ohlone case omitted) in water, allow the threads to  
moisten, open the lid, moisten the material inside, and then dispose  
of it as a flammable solid or a toxic liquid.  In fact, this process  
is required before transportation if the moisture level is unknown  
(since transportation of dry - by which we mean <10% by weight water)  
picric acid on public roads by motor vehicle requires substantially  
more training and certification per 49 CFR 172.101 et seq.

Your coverage neglects to cite the basis of the declarative comment  
that picric acid has been banned on college campuses.  This news  
hasn't come to campuses across the country - the purchase of picric  
acid is a matter of routine, especially for tissue staining (Bouin's  
stain) and organic synthesis.  Specialty chemical companies sell it  
regardless of the ban you report.  If this is a quote, you failed to  
attribute it.  If it's speculation, it's mistaken, considering the  
evidence to the contrary. Either way, it's erroneous to include that  
report in the coverage as you chose to.

Picral is a 4% (by weight) solution of picric acid in ethanol - the  
ethanol is not a neutralizing solution (it is not a base, though  
picric acid is an acid), it is a stabilizer.

Your conclusion that temperature (an inaccurate term from the  
perspective of basic thermodynamics - "heat" or "high temperature"  
would have been more appropriate) or motion could have made the  
picric acid explode is unfalsifiable - without actual experience  
(i.e. testing or an unexpected explosion) one cannot deduce whether  
this material was sufficiently dry to be shock sensitive.  Picric  
acid, when 10% wet - adequate to stabilize, appears as a flowable  
solid.  That is, it looks dry, but it may well not be so.  Prudence  
is the proper course of action in any case where the true degree of  
wetness is unknown, but nothing short of an explosion indicates  
whether this or that picric acid was actually dry enough to be shock  
sensitive.

Whether Decon Environmental or the Fremont Fire department knows the  
details of picric acid or not is pure speculation.  In my experience,  
the FD prefers not to handle things that might be explosive, whether  
or not they are, and hazardous waste technicians often lack  
experience in the subtle chemistry of organonitrates from laboratories.

Regardless, though, 25 grams of high explosive is a small explosion.   
By comparison, the M61 Fragmentation Grenade uses 5.5 ounces of  
tetryl as its energy source (according to http://www.fas.org/man/ 
dod-101/sys/land/m61.htm), and has an effective range (casualty  
radius) of 15 meters, a function more of the shrapnel than the energy  
source.  A high power rifle cartridge may have one half an ounce of  
gunpowder (a low explosive) as its energy source (according to http:// 
www.nextag.com/338-rifle/search-html).  The rifle and grenade both  
increase their potency by enclosing the explosion in metal - far more  
effective at maximizing power than glass (or plastic, another detail  
your article omitted).  This essentially brackets the potential power  
of the material, had it been, in fact, shock sensitive.  Somewhere  
between the charge in a grenade and the charge in a high-powered  
rifle bullet.

Based on my experience with explosive deactivation of reactive  
chemicals, I believe that the Alameda Bomb Squad had to initiate the  
explosion with something; I suspect they used det sheet and det cord,  
which would have increased the explosive mass in the explosive  
construct by as much as an order of magnitude or more.  I suspect  
that an explosion of exactly the same construction, except without  
the picric acid, would also shake the campus and set off car alarms.   
Your coverage omits these details, so all we have is speculation.

The science is the science and the facts are the facts.  In my  
opinion as a chemist, indignation - which appears to be rife in your  
coverage - over Ohlene's approach to hazardous materials handling  
grants you no license to abbreviate the science in the matter.

John

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