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Defend Yourself From Benzene Emissions When Driving on Gasoline


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Self paced silent presentation of some safety tips to avoid dangerous inhalation of benzene as we drive, fill-up and park in your garage. Benzene is a potent carcinogen that causes cancer, especially leukemia. We are exposed to much greater concentrations of benzene than OSHA and NIOSH say is safe. But there are some very simple precautions that you can take to significantly lower the dosage you are getting now. You just have to be made aware of the difficult medical situation that driving on gasoline has put us into.

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Defend Yourself From Benzene Emissions When Driving on Gasoline

  1. 1. Defend Yourself From Benzene EmissionsWhen Using Gasoline Bob Falco, PhD Professor of Mechanical Engineering Director, Institute for Energy Resourcefulness
  2. 2. Cancer rates in the US Newsweek Oct 2012
  3. 3. 1/3 of the cancer risk in the US is due to vehicles ―The average cancer risk in 1999 for Americans was forty-eight in a million, and 29% of this risk was attributable to mobile sources— which works out to a mobile-source cancer risk for the average American of about fourteen in a million.‖ in an ADDITIONAL 4340 deaths every year! This resultsEPA Technology Transfer Network National Air Toxics Assessment, 1996
  4. 4. Gasoline contains Benzene, and Vehicles create additional Benzene from burning exhaust in their catalytic converters Created in the catalytic Added at the refinery converter
  5. 5. Benzene is the major CarcinogenBenzene produces leukemia
  6. 6. No agreed upon minimum exposure that is safe!Health numbers differ by100 million timesRegulatory advisory numbersdiffer by 1000 times We don‘t know how dangerous benzene is!!! EPA Jan 2012
  7. 7. The EPA Cancer Odds Increased cancer deaths 13-45 micro grams per cubic meter  1 in 10,000 increase in cancer deaths (30,000/year) 1.3-4.5 micro grams per cubic meter  1 in 100,000 increase in cancer deaths (3,000/year) .13 to .45 micro grams per cubic meter  1 in 1,000,000 increase in cancer deaths (300/year)
  8. 8. Ways You Are Exposed to Benzene from Gasoline and the Amounts Inhaled
  9. 9. Vapor release during gasoline refuelingWe can‘t see the benzene that this special camera shows as black smoke, but we can smell it.
  10. 10. Do you smell the sweet odor of benzene when you fill-up? BENZENE HAS AN ODOR THRESHOLD OF 5 MILLEGRAMS PER CUBIC METERThus, if you are smelling the sweet odor of benzene asyou fill-up you are being exposed to 1000 times thatdetermined the 1 in 100,000 number, so that a 1 in 100 chance of getting cancer. Of getting leukemia!
  11. 11. EPA benzene vapor protection Phase II installed in 1993 -60% effective ORVR in all vehicles newer than 2006 – 98% effective
  12. 12. Benzene emissions during fill- up if ORVR is 98% effectiveWhen filling your gas tank the EPA expects emission of 12 ppm over the5 minute fill-up.The industrial standard set by OSHA for the Short Term Exposure Limit is 5 ppm over 15min.The industrial standard set by NIOSH for the Short Term Exposure Limit is 1 ppm over 15min. Thus, The amount coming out of your tank is 2.5 times the OSHA STEL and, 12 times the NIOSH STEL
  13. 13. Recommendations To avoid evaporative emission exposure:1. Do not stand over the gas tank while filling it.2. Lock the nozzle ‗open‘, and walk away.3. Close the windows and doors of your car when filling – especially if you have children in it.Note: the benzene level in the convenience store are likelymuch higher than outdoors.
  14. 14. Exhaust Emissions Three-way catalytic converter does reduce benzene emissions in the normal range of driving. However, when accelerating from rest or driving at high speeds the catalytic converter produces more benzene. Furthermore, as shown a few slides ahead, when the catalytic converter is cold, as it is for a few minutes after starting your car, it the benzene emissions.
  15. 15. The Exhaust Plume 1 in 10,000Car following in lane Where should you position your car?
  16. 16. The Exhaust Plume 1 in 700,000 1 in 10,000 At 2 ½ car lengths you are exposed to 1/36 the amount of benzene as at the tail pipe. If you stay right behind the vehicle in front of you,your car is in taking a good portion of the plume, which has benzene concentrations that result in an additional 1-in-10,000 chance of cancer if inhaled regularly.
  17. 17. Catalytic Converter Benzene Generation Benzene (pre-catalyst) or, Benzene (post-catalyst) during cold start 75 mphAt high speed, greater than 75 mph, you should drive even further back .
  18. 18. Cold Starting When your car is cold started, or you are driving behind one that has just been started, the catalytic converter is not removing the benzene (left plot on previous slide). In this condition the curve on the left (previous slide) shows that the amount of benzene is very, very high at all speeds. Often, when in city driving, you are on the road along with your neighbors going through lots of lights on the way to work while your car is warming up. Conditions are very bad.
  19. 19. RecommendationsThe spreading of the exhaust plume is asymmetric and youget its full effect as you follow behind in-lane.1. When in moving traffic, try to stay at least 2 ½ carlengths behind the car in front of you. Your dose will be 1/36 of the emission level at the exhaust pipe.2. When stopping for a light, stop at least 1 car lengthbehind the vehicle in front of you. Although the ―accelerationblast‖ (see last slide) is up to 20-30x steady state, it willdiffuse to ½ - ¼ that which exists at the exhaust pipe at 1 carlength distance. This is still a high dose. And is especiallyhigh if you‘re in traffic full of newly started cars.
  20. 20. Gas Tank Cap Leaks It is estimated that 200 lbs of gasoline leaks from the average cars tank through the gas cap per year. This is 25 gallons. The biggest problem is that this gas will collect in your garage.  So you get a good dose as you enter your garage.  But, perhaps worse, if you have an attached garage, it will get into your house.
  21. 21. Recommendations Check the tightness of the gas cap. Replace it if leaks are found. Benzene is very volatile and leaks easily. Let your garage ‗air out‘ before entering it. Make sure the garage door leading into your house is well sealed. Vent your garage.
  22. 22. Benzene effects are cumulative
  23. 23. EPA has just enforcedthe 0.62% benzene limit. Reduction from 1.05% Vapor emission during filling will be halved, but still over the OSHA and NIOSH STEL limits by 125% and 600% This does little to change the exhaust emission picture, for as the Swiss studies show:  when cold starting,  when accelerating,  and when driving at high speed, the benzene emissions can be up to 100x the steady state rates. And, the EPA allows refineries to trade benzene credits. A result is that some regions are suffering – see next slide.
  24. 24. Oregon example
  25. 25. Conclusions The effects of the exposure to benzene are long term. Think of them as you do the effects of smoking. The western world, and particularly the US has very high rates of leukemia compared to the rest of the world.I leave it to you to decide whether to ignore the precautions.I also want to make you aware that your car does not need to run on gasoline, and can actually run better on alcoholslike ethanol and methanol (see presentations in references on the following slide).
  26. 26. References Falco -- YouTube Channel on Alternative Fuels  w=grid&view=1 Falco SlideShare Site 