Thursday, May 26, 2016

Reason to sample close to a source during a mold investigation

Below grade abandoned electrical outlet




SAS 180 air sampler
Air sample in control area

Air sample in room using DG-18 Outside air and hallway control on right
Air samples below the floor DG-18
Indoor air samples for 100 liters were taken in a below grade room.  Occupants in the space reported a musty odor.  Air samples in the breathing zone did not find a problem.   Air samples below the floor had elevated levels of Aspergillus spp. and Penicillium spp.  Outside air sample 50 liters. 



Sunday, April 17, 2016

Cell phone Infrared camera -FLIR One

FLIR-ONE infrared image of classroom just after students left - N. Carlson
The above image shows dark seats where students did not sit and purple colored seats where students were sitting at a class where I had just been a guest lecturer.

I am currently weighing the purchase of two low cost IR camera attachments. A FLIR One and a Seek thermal imager.  The models that can be used on some android phones and other models that can be used on most i-phones.  Because of the location of the charger on some android phones it will be necessary to use cord to allow camera to attach to the phone. The FLIR One needs a battery to operate the Seek does not.  The FLIR has better image quality with a wider field of view.  The Seek has a wider temperature range.

Amazon has the FLIR ONE Thermal Imager for Android available for less than $300.


FLIR-ONE versus SEEK infrared camera - 3 minutes

Jet air driers disperse viruses




Fortune Magazine reports on a study of virus dispersion comparing drying with warm air, drying with a towel and Jet air drying.    The mechanical energy provided by the jet air drier dispersed non infectious viral particles in the air 60 times more than warm air driers.  The safest method was a paper towel.  The warm air dryer distributed more viral particles than paper towels but less than the jet drying model.


Jet air drier particle distribution - TOMO news - 1 min.

Wednesday, March 23, 2016

Butanediol production from corn and sugar beet stover

Corn Stover
Researchers at the University of Minnesota have found a more efficient way of  first producing Tricarboxylic acid (TCA) from inedible lignocellulose parts of plants.  The TCA is then converted to butanediol (BDO)  The raw material of orange peels, corn or sugar beet stover are digested by modified E. coli bacteria in a 5 part process to produce butanediol  BDO.

Over a billion pounds of BDO containing spandex are produced each year for clothing and furniture.   The pathway could also be used to produce chicken feed and food additives.

An abstract of the article, Engineering nonphosphorylative metabolism to generate lignocellulose-derived products, appears in the Journal Nature Chemical Biology


Use of corn stover (leaves and stalks)  for cattle feed - 2 min. 


Optimizing the amount of corn stover removal for no-till agriculture - 3 min.

U of MN Duluth to receive Solar feasiblity Grants from NREL


Solar Panel at the UMD Bulldog Football Stadium

The National Renewable Energy Laboratory (NREL) will be providing solar feasibility grants to eight college campuses including the University of Minnesota Duluth.  As part of the Department of Energy's Sun Shot Initiative, NREL will assess possibilities and economic payback for the installation of photovoltaic cells on campus. This will also provide learning opportunities for students and faculty on campus.


DOE Sun Shot - SHINE initiative for Solar Power - 2 min. Jan. 2016.

Thursday, February 11, 2016

Carbon dioxide deaths due to soda fountain cylinder leaks

image by Mikael Häggström
There will be changes to how building codes handle the location, monitoring and ventilation of carbon dioxide cylinder storage.  The changes are the result of fatalities at several locations where  carbon dioxide cylinders were venting into small spaces.  The carbon dioxide displaced the oxygen and death resulted.  For small restaurants, the cylinders can be located outside the building.  This may be a concern for larger buildings where the cylinders can not be stored outside.

Carbon dioxide should not be confused with carbon monoxide which is produced by incomplete combustion.  According to US OSHA the carbon monoxide 8 hour exposure limit is 50 ppm.  The eight hour exposure limit for carbon dioxide is 5,000 ppm.

Carbon dioxide connections inside an enclosure at a Sanford Florida McDonald's restaurants in January of 2005 led to the death of two individuals - Orlando Sentinel





Friday, January 29, 2016

Foldscope evaluation of suspected mold growth in records room



Suspected mold growth on drywall in a records storage area (photo - N. Carlson)

Close-up view of suspected mold growth (photo - N. Carlson)
Previous problems with leaks in this space caused suspected mold growth on the wall and pipe insulation in this records storage space.  3M Scotch Transparent Tease tape samples were taken from the surface.  The tape was placed on a microscope slide using clear fingernail polish as a mounting fluid.  Photos were taken with Foldscope microscope attached to a Samsung S-5 Cell phone.   Photos were cropped using Adobe Photoshop Elements 12. Click to enlarge photos.

Uncropped photo of Chaetomium spp. (N. Carlson
Cropped Foldscope image of Chaetomium spp. from wall (N. Carlson)

Cropped Foldscope image of Aspergillus spp. from wall (N. Carlson)
Suspected mold growth on pipe insulation in records storage area (photo - N. Carlson)
Cropped Foldscope image of Stachybotrys spp. (N. Carlson)

Wednesday, December 16, 2015

Foldscope mold evaluation after repeated roof leaks

Suspected mold growth on sheetrock after repeated water events - N. Carlson
A rental property had sustained repeated water damage from a roof leak.  Suspected mold growth was noted behind the vinyl baseboard.  Tease tapes were taken from the surface and clear nail polish was used as a mounting fluid for clear transparent tape on a microscope slide.  Click on any photo to enlarge.

Foldscope image of Chaetomium spp. spores  from Samsung S-5 camera -click to enlarge - N. Carlson
Cropped photo of Chaetomium spp. spores with Adobe Photoshop elements - N. Carlson
Foldscope photo of Chaetomium spp. perithecia - N. Carlson
Cropped photo of Chaetomium spp. perithecia with Adobe Photoshop Elements - N. Carlson
Suspected mold growth in the adjacent room behind the vinyl baseboard - N. Carlson
Foldscope image of Stachybotrys spp. using Samsung S-5 camera - N. Carlson
Cropped photo of Stachybotrys spp. using Adobe Photoshop Elements - N. Carlson
These samples were taken after a weekend water event.  These particular organisms typically growth on paper products receiving repeated water damage.  The growth observed is unlikely to be as a result of a single water event.

The Foldscope images were clear enough to allow me to identify the organism to the genus level.  After taking the picture, I used the zoom feature of the camera to make the field identification.  I used an overhead fluorescent light bulb to back light the microscope slides.

Wednesday, December 9, 2015

Paleolithic sleep patterns are similar to modern sleep patterns

Health Effects of Sleep Deprivation - Science Kids - click to enlarge

Research on sleep patters from our paleolithic ancestors found that an 8 hour sleep pattern was not the norm.  This according to CNN - Sleep like your ancestors. 

According to the Washington Post, three of the existing hunter gatherer tribes slept an average of 6.5 hours per night.  This is very similar to the average measured hours of sleep for the UK.  The British sleep times average 6 hours and 39 minutes per night according to the Great British Bedtime Report - 2013.

From the Washington Post, the paleolithic ancestors were much healthier on measures of chronic disease indices of BMI, and blood pressure.   The authors speculate that the we are unhealthy because we are unhealthy and it may not be due to lack of sleep.

Conclusion:

Cut yourself a bit of slack if you aren't sleeping 8 hours.  It is important to sleep as fatigued individuals have more accidents, it allows people to reduce toxins in the brain and  allows the brain to work on diffuse learning wiring connections while you sleep.  It is a myth that our ancestors slept more.


Memory and Sleep - Penny Lewis - 7 minutes




AIHA - Mold Resource Center



Mold growth - N. Carlson
The American Industrial Hygiene Association (AIHA) has an AIHA online mold resource center.  The page provides links and general facts about mold and includes past references to articles in the Synergist for AIHA members.  The articles about proper health and safety precautions after the cleanup after Hurricane Sandy are useful.  The site provides good information useful for first responders and safety professionals after a water related natural disaster. . 



Mold in homes - 5min.

The discussion in the video mentions keeping the relative humidity (%RH) between 40% and 60% in the home.  This is acceptable for summer time but indoor humidity levels above 20 to 30% in winter climates can cause problems with moisture condensation on cold surfaces.