Monday, April 30, 2012

Good introductory video on Penicillium mold.

Penicillium citrinum - N. Carlson

Penicillium spp. line drawing N. Carlson

IAQ Video Network has produced a good introductory video on Penicillium spp. mold.  This mold is often a primary colonizer after a flood.  Growth will often start on surfaces within 60 hours after a water event.  If water damaged carpet is not properly dried it will often grow on the trapped nutrients available nutrients. DG-18 contact agar sampling has been a QC method for detecting this mold.  This mold will also grow off of dust in environments where surface relative humidity levels are above 70%.

Please review a previous post on this blog for contact agar and tease tape samping information.

Wednesday, April 25, 2012

Mold litigation

In 2009, St. Joseph's Hospital, Tampa was sued alleging that failure to control dust exposure from a nearby remodeling project caused Aspergillus lung infections in three children who later died.  I have been unable to locate additional information on the outcome of the lawsuit.

In New York an Appeals court has allowed a tenant to sue the owners of her Manhattan apartment building for mold exposure.  A report by Tom Scarlett notes that a tenants health symptoms were noted on October 1, 2003 when a new owner began renovations in the basement.  The case is Cornell v. 360 W. 51st Street Realty.
More information is available from the New York Observer.

Monday, April 23, 2012

U of MN Solar House

The U of MN solar house incorporates features to improve solar efficiency and improve the durability of the house.  The asymmetric roof is a modification of an A framed house.  The red cladding keeps the moisture out of the house allowing it to breath. The house produces 13 months worth of energy.   It took engineering first place in the 2009 competition.

Longer version below

Combustible dust hazard

The USCSB (US Chemical Safety and Hazard Investigation Board) has released a video on combustible dust hazards - which varies from resin, rubber dust, nylon fiber, sugar, coal to aluminum.  The video has some helpful animations showing the cause of the aluminum dust explosion.  The video contains some adult discussion about fatalities parents should review this to determine if it is appropriate for children.  


Dust explosions require the fire triangle of fuel, oxygen and ignition plus dispersion and confinement. A dust layer as thick as a dime (1/32 inch or 0.7938 mm) covering 5% of a room surface area is sufficient to cause and explosion.  Dust on suspended ceilings can often cause the problem because it is not visible. 
Click on the link above to get a pdf of the combustible dust chart.

Sunday, April 22, 2012

Terahertz imaging applications

A flood of articles on the use of terahertz imaging suggests opportunities for improved instrument detection in several areas including security, quality control and medical imaging. - Click on image to enlarge - click on image to enlarge
The terahertz frequency is close to the IR spectra and may be useful for moisture detection.  It will also be useful to find objects inside a wall cavity.  Unlike the IR spectra it is capable of detecting materials below the surface of the object and therefore will raise privacy concerns.  

Researchers at the University of Texas in Dallas have devised a chip for a smart phone allowing it to see through walls using terahertz imaging.

The new energy economy

Micheal Noble of MinnPost offers up some ideas about the new energy economy in a recent article.   He points to increased fuel efficiency requirements of vehicles and improved power grid infrastructure that will allow better use of fossile fuels and easy use of renewable energy.   Although it is not mentioned in the article. The 5 Billion dollar improvement to the transmission lines is needed to get stranded windpower to larger cities.

Conservation and improvements in energy efficiency in the US may just translate into cheaper coal for other countries.  A proposed new coal terminal in Bellingham, Washington would provide a transport route for cheap western coal to China.  The Seattle Times notes that the earliest construction would be 2015 or later.  The article outlines the typical debate over jobs and concern for the environment.  Residents are also concerned about dust generated during coal transport.

Saturday, April 7, 2012

Fuel economy payback for hybrid vehicles

Chart of years to break even comparing hybrid and non hybrid models given regular gas at $3.85 per gallon and diesel at $4.14 per gallon.
Given this information it is interesting to note that Chevy Volt sales have increased in March of 2012.
From  1,023 in February to 2,289 in March.  The previous best selling month was December of 2011 when 1,529 were sold.

Friday, April 6, 2012

Upcoming mold remediation course in April, 2012

Update.  The course was successful with students from around the state.  There may be another offering in 2013.  There was also some interest in a two day fungal identification course.  Please email Center for Public Health Outreach for more information.

16 hour mold remediation course was held at U of MN Minneapolis Campus from 8AM to 5PM April 24 and April 25th, 2012.  The class was at capacity. Instructors were Troy Blanchard, Mike Buck, Neil Carlson and Sean Gabor.

Wednesday, April 4, 2012

MN has geothermal energy potential

Minnesota has more geothermal energy potential than first thought.  John Myers from the Duluth News Tribune reports on progress from NRRI researchers from UMD and North Dakota.  West and Central Minnesota have the greatest potential.  The closed loop water system involves drilling 20,000 feet (6,096 meters) below the earth surface.  Temperatures at this location reach 120 degrees Celsius or 250 degrees F.

Cost for electricity generated by this method is estimated at approximately 10 cents per kilowatt hour.  On the plus side it is less variable than wind energy and does not produce carbon dioxide.  On the minus side, there are concerns about ground water polution. 

The use of carbon dioxide as a gas to transfer heat was discussed in a previous blog post.  The well would not have to be as deep.  The cost may also be less.
The US 48 states with more geothermal potential are in red.   Those with less potential are in blue.