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RE: Risk



I agree with Ruth Weiner's thoughts about using perceived risk as a basis for risk management, but disagree strongly with her example.
-----Original Message-----
From: RuthWeiner@AOL.COM [mailto:RuthWeiner@AOL.COM]
Sent: Friday, November 16, 2001 7:18 AM
To: jjcohen@PRODIGY.NET; ncohen12@HOME.COM; radsafe@list.vanderbilt.edu
Subject: Re: Risk

I am going to say this and get a lot of grief, I am sure.  Decisions should NEVER be made on the basis of perceived risk!  Make a decision that way, and you will be sorry.  Treating perception like reality is not only a cottage industry for anti-nukes, it is downright stupid and dangerous.  Perceived risk might result in some faintly interesting sociological studies but that's about it.

Example:  if asbestos had been used above the 60th floor of the World Trade Center, the buildings might possibly have stood more than an hour, and many lives might have been saved.  But EPA applied the linear non-threshold theory to asbestos  (this was the "perception") and prohibited its use (at least that is my understanding).

If people perceive a risk much different from the realistically estimated risk, let's just tell them they are wrong.  I recognize that DOE and NRC pander to perceived risk, but that doesn't mean everyone has to.



Ruth Weiner, Ph. D.
ruthweiner@aol.co 
 
 
=====================
 
This bit about the non-use of asbestos at the WTC seems to have originated with a distasteful 14 September 2001 op-ed piece Steve Milloy wrote for FoxNews.com.  Milloy's piece and a 15-16 September follow-up are available at Milloy's website, www.junkscience.com.
 
Milloy alleged that in 1971 New York City outlawed the use of spray-on asbestos insulation in construction in the city.  He said that asbestos had been used up to the 64th floor of the WTC North Tower.  Other materials were substituted for the balance of 1 WTC and all of 2 WTC.  Milloy offers that "not everyone was convinced they would work as well".  His only named "not everyone" was Herbert Levine, President of Asbestospray, who he quotes as saying "if a fire breaks out above the 64th floor, that building will fall down".  Milloy says that instead of the WTC tower structural steel insulation protecting the buildings for 4 hours, per specification, they collapsed in 56 minutes and one and a half hours.  He attributes many deaths in the buildings to the shorter time to collapse, for which he blames the NYC regulators.
 
The only named individuals cited by Milloy were Levine, now deceased, and Harvard physics professor Richard Wilson.  I asked Wilson whether Milloy had correctly represented his thoughts.  He replied, "Unlike most responsible reporters he did not check his writing with me for accuracy of fact. I have looked at the website to which you refer, www.junkscience.com, and the facts seem about right, although I disagree with some of the opinions based upon the facts."  Wilson continued, expressing the opinion that asbestos insulation might be 25% better that its replacement and offering that settled policy in high-rise fires was to use helicopters to spray foam on the fire to cool it down and to remove people from the roof.
 
Much of what Milloy wrote in his op-ed piece and some of what Wilson wrote in his email to me seemed suspect, so I did some research.
 
If you look at what Marks' Standard Handbook for Mechanical Engineers and the Fire Protection Handbook have to say about structural steel insulation, it becomes clear that there is nothing magical about asbestos in this application.  It was used because it was less expensive that the other spray-on materials and cheaper to apply than the non-spray-on alternatives.  Other materials, specifically mineral wools, have equivalent or better insulation properties.
 
However well the insulation would perform in a "normal" fire, the airplane impact certainly damaged the insulation on several floors and the intensity of the jet fuel fire was much greater than anything considered in the design of the building.  The South Tower was struck at lower floors and failed earlier, as engineering intuition would suggest.
 
If you read the NYTimes heartbreaking obituaries of the WTC victims, it becomes pretty clear that most of the victims were on floors above the airplane impacts and were unable to evacuate down the stairwells past the fire-involved floors.  The doors to the roof were locked, partly because of a long-standing power struggle between the NYFD and NYPD.  The police have the helicopters and the fire department has argued that high-rise fires should be fought by fire-fighters inside the building.  This dispute was discussed in a WSJ or NYT article that I don't have available at the moment.  The article noted that there are two technical and one social complication supporting non-use of helicopters.  The fire can create high turbulence around the roof and the fire plume may have too little oxygen to allow the engines to function.  The social problem is crowd control, if several hundred or thousand people are on the roof awaiting rescue.  A few dozens of people have been successfully rescued from roofs in serious, but altogether less catastrophic, high-rise fires.
 
A NY Times 18 Sept story by James Glanz and Andrew Revkin looked into the asbestos insulation issues.  They found that the WTC builders stopped using asbestos 40 floors up in the north tower; the 1969 decision was made by the NY/NJ Port Authority in response to developing epidemiological information on the connection of asbestos with mesothelioma.  NY City extended the ban to all construction in the city in 1971.  The NY Times article says that both the asbestos and the non-asbestos insulations were supplied by United States Mineral, where Milloy says that Levine's company Asbestospray supplied the asbestos insulation.
 
The newly-created EPA doesn't seem to have been involved in any way in any of the WTC decisions.
 
Milloy's allegations seem to have become instant conservative, anti-regulatory myth, bringing to mind Twain's aphorism that a lie or a half-truth can get half-way around the world while the truth is putting on its shoes.
 
Best regards.
 
Jim Dukelow
Pacific Northwest National Laboratory
Richland, WA
jim.dukelow@pnl.gov
 
These comments are mine and have not been reviewed and/or approved by my management or by the U.S. Department of Energy.