Thursday, April 7, 2011

The Next Asbestos

Thinking back about posts I made regarding taking shortcuts or letting your critical thinking skills take a back seat, I've come to the realization that engineers are letting social pressures determine right from wrong more so than ethics and morals.  This is a disturbing trend if true.  Maybe it is due to the incredibly good job engineers do of making it look easy that the lack of prestige is making us lax in our profession.  I hinted that engineers are letting others define their abilities based on "requirements" to follow standards instead of using their own aptitudes to design a safe, reliable solution.

But in the context of those posts that were referring to GREEN standards, I thought of a possible shortcoming based on our own shortsightedness.  It is not a problem we can resolve, it is only human nature, and therefore deserves some discussion.

Lung Tissue with Asbestos Tumors
Historical Perspective
Consider an engineer or architect in the late 19th century.  The customer is demanding better efficiency and lower cost of ownership.  You, the engineer, look up the equivalent of matweb for a material that is inexpensive but has great sound proofing; suitable strength; and resistance to heat, electrical, and chemical damage.  You come across this cutting edge additive called asbestos.  It's naturally occurring, so it must have limited health risks.  It can be mixed with cement for structural applications.  It can be woven into fabric for wrapping pipes or hanging sheets.  It can be cast or processed into ceiling tiles, floor tiles, and even shingles.  This is a magical multipurpose material.  It is not until decades later that we realize the harm asbestos can do to lung tissue.

And now we live in a similar age.

Space Age Additives
I'm that engineer.  When I bought the house I'm currently living in, I really needed to repaint some of the rooms.  I heard about this nanoscale ceramic bead paint additive used by NASA to help insulate the space station.  It was reasonably affordable and would save me plenty of money in my energy bills, especially in the hot Arizona summer.

I bought some in bulk and mixed it in with the paint.  I even put it in the paint I was using for the ceiling, since that surface was adjacent to the attic and a large source of heat transfer.  Painting the inside of the house in August, I could literally feel a difference (when painting the ceiling) between the areas I had painted and the areas left to paint.  The areas coated with the additive were noticeably cooler.  When I get my comparison statement from the electric company, my energy usage is always significantly lower than the average home my size.  Although my family makes a very conscious effort to minimize our usage, I am from Wisconsin and don't take well to the heat, so there are times when we don't necessarily conserve as much as others.  Therefore, conservation can't be the only reason my energy rates remain below average.  But, since I painted the house right when I moved in, I don't have any numbers of the house prior to painting to know for certain.

None the less, my house is 10 years old and due for a fresh coat of paint on the outside.  I have every intention of using this additive again.  Afterall, with that level of savings from only a few rooms painted, imagine the savings with the entire house painted.  Not to mention, the additive is only 30% efficient insulating conductive heat transfer (inside walls).  It is 90% efficient at insulating radiative heat transfer (outside walls).

The Downside
Much like asbestos, there is reason to believe that these nano technologies may pose a serious long term health risk.  It is well known that benign materials take on unhealthy side effects when made smaller (and more easily absorbed into the body).  Although the additive I used is completely neutral when in the paint, there are warnings on the packaging about not breathing it in raw form.  So then, what about when he house gets remodeled.  Or what about when a microburst takes out a piece of the house.  Either way, someone will have to clean up the mess - a mess that may contain exposed nanomaterial.  Does my house all of a sudden turn into a hazardous waste site?  Am I responsible for remediation?

Much like asbestos in the late 19th century, it is too early to tell.  With the information and knowledge we currently have, there is no risk and the savings (monetarily and environmentally) is too great to pass up.  Perhaps in the future we'll know more and can make a better informed decision.  For the time being, this engineer is going to use his own brain and not wait for the government to develop a standard on its use.  The benefits out way the risks.

Concluding Remarks
These are the types of decisions we get paid for.  Engineers are supposed to use their education and experience to make decisions just like this.  We rarely have all the information.  Use of good judgement is required to fill in the blanks to make the best decision at the time.  Why delay the benefits of new technology while some administrative board determines policy?

2 comments:

  1. Great thoughts. Lead used as an additive is a good example also. I think you bring up a good discussion point about how as engineers we really haven't looked well at long term human health risks with new (and not so new) technologies. It seems almost all standards testing has nothing to do with that.

    I also would like to say that there is tremendous pressure from upper management to be "green" or "sustainable." They don't seem to understand or want to understand real consequences from such policies. One thing that comes to mind is the transfer of hexavalent chromate to trivalent chromate. Trivalent simply does not hold up as well as hexavalent, and therefore we have to use thicker coatings. The cost to re-plate parts is huge, plus all the fit problems we've experienced has caused huge costs in re-designing.

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  2. The content of your article was very thought provoking. You bring up some very good points on ethics that unfortunately, many engineers forget. However, the bottom line should not always the highest weighted factor in a project. Each individual engineer has a responsibility to ethicaly conduct the due diligience on the process/materials they are using or recommending for use. Only then, can educated decisions be made about balancing risk, effectiveness and cost. 

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