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.


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.

Sunday, November 22, 2015

Soot sample collection

Soot damage from a small fire in a building - Another reason to stay low in a fire.
Soot damage after a fire is common. Soot particles have been linked to health problems in chimney sweeps as far back as the 18th century (AIC News 09-2010)   

Sampling the soot can be done with a swab or an air sampler with later chemical analysis done by a laboratory.  As a preliminary test, an Air-o-cell cassette air sample can be taken from the area.  The soot particles have a fairly easily recognizable shape.  The individual soot particles are often less than 2.5 microns but will be attracted together in larger masses as seen in the photo below.

Air-o-Cell air sample of  a soot particle - microscope photo:  The distance between 0 and 1 is 25 microns.
As an experiment a co-worker assisted me with sample soot particles on a floor some distance from the source of the fire. We noticed that the particles had a strong static charge and were easily sampled from a distance of 1/4 to 1/2 inch (approximately 1 to 2 cm).

Soot sample collection - N. Carlson - 1 min. 

Friday, November 13, 2015

16 hour Mold Remediation Course April 13-14 2016

16 hour Mold Remediation
This two day course offered April 13 - 14, 2016 by the University of Minnesota, Twin Cities  is designed to train individuals who are or who anticipate being employed at a mold remediation work site.  Individuals in charge of building maintenance and public health officials inspecting water damaged buildings have also benefited.  Past attendees have also come from Hospital Facilities Management. 

Activities in this course include implementing the emergency response plan, identifying specific molds and associated health hazards, selecting protective equipment, and performing advanced control containment or confinement.  Additional site-specific training for emergency response must be provided so individuals can carry out any role, which may be assigned during a response. 

For more information sign up at the U of MN HazMat and Hazwoper Training site:  Mold Remediation Course.

Friday, October 30, 2015

Mystery Photo

Mystery photo - click to enlarge
Please offer comments and best guesses about the above mystery photo.  It has not been digitally altered. 

Friday, October 9, 2015

Reducing deaths due to attractive nuisances

Weisman Art Museum - N. Carlson
This past Thursday, October 8, 2015,  I had the privilege or discussion several topics of interest with members the the University of Minnesota and Hennepin County at the Weisman Art Museum.  The participants were able to choose from 21 discussion topics for approximately 45 minutes each.  For the last topic, our group discussed the problem of physical structures that are attractive nuisances.  Playing and exploring these structures frequently result in injury or death usually to youth and young adults.


Provide matching grants to communities or local neighborhood groups abating attractive nuisance hazards.  These include dangerous abandoned buildings and structures of heights greater the 4 stories.

Skateboard damage prevention - N. Carlson
Examine how to generally apply the lessons learned from the construction of skateboard parks.  These added features make skateboarding less practical have worked to reduce damage to public property and  injuries to skateboarders.

We also explored the neurochemistry of risk taking in teenage youths and young adults.  What rights of passage or other rituals can be used to provide the same thrill of danger and accomplishment.  One person took up skydiving to experience the needed adrenaline rush.  After 17 dives the person came away less than satisfied as the experience didn't have enough danger.

How can the energy of this fearless behavior be channeled toward some positive benefit to society? Can we use the neurochemistry studies from Jane McGonigal’s book, Reality is Broken, and create a positive addiction to behaviors that are challenging and beneficial.

Examine the architectural features of German buildings that prevent urban exploring.  Apply these designs to structures combining utility and architectural aesthetics.

Make the Call - Washington Ave. Bridge - N. Carlson

Redesign the railing on the Washington Avenue Bridge to make it difficult to jump but not significantly limit the sight line and view of the Mississippi River. 

Several studies suggest that making the irrational behavior of jumping off a bridge more difficult will reduce deaths due to suicide as these individuals are less likely to try other means of suicide. 

The dangers of Urban Exploring - 4 min.

Saturday, October 3, 2015

Mold growth in an attic

Suspected mold growth in an attic - flash on camera
I was asked by a home owner who was selling his property to determine if the white specks under the roof in his attic was mold growth.  In this case, I chose to charge a flat fee that would allow me to take as many samples as I needed to make sure I identified the organism.

Safely sampling the material was a bit tricky.  I attached clear double stick tape loop onto the end of a telescoping camera tripod.  I taped the inside of the loop onto the tripod to prevent it from coming off during sampling.  The homeowner stabilized the ladder while I took samples.

Suspected mold growth in an attic.  - No flash on camera
I also took photos of the attic without benefit of a flash. The images were a bit blurry but more accurately depicted the light cream color of the mold growth.

Bathroom exhaust vent
At this point in time, we are not sure about the source of moisture in the attic.  There were some leaks noted in the bathroom exhaust vent.  Local abatement contractors were referred to the home owner for the remediation work.

Photo micrograph of Chrysosporium spp. taken from a tease tape of the attic roof- lacto fuchsin stain
The above photo was taken with a Samsung S-5 camera phone through the eyepiece of a Nikon microscope. There is a distance of 25 microns between the 4 and 5 on the ruler.  The image was cropped using Adobe Photoshop. Some species of Chrysosporium spp. can be a rare opportunistic pathogen for individuals with compromised immune systems.

The organism, Chrysosporium spp., is causing health problems for Timber Rattlesnakes - 5 min.

Monday, September 21, 2015

Field identification of moldy hay with foldscope

Moldy Sudan Grass Hay
As a test of concept, I wanted to determine if a Foldscope cellphone microscope could be used for field identification of fungal growth on hay.  The answer is yes for the darker colored organisms.  I took a tease tape of the suspected hay material.  The 3M clear Scotch tape was attached to a microscope slide using clear fingernail polish as a mounting fluid.  The Epicoccum spp. and Alternaria spp. spores can be seen.  The Cladosporium spp. spores are tougher to pick out in the background.

Photo of Epicoccum spp. through Foldscope attached to Samsung Galaxy S-5 camera
Photo of Epicoccum spp. cropped and enlarged with Adobe Photoshop
Photo of Epicoccum spp., Alternaria spp.  and Cladosporium spp.  taken with Samsung Galaxy S-5 camera through the eyepiece of Nikon Microscope 400x.  The distance between 5 and 6 is 25 microns.

Monday, September 14, 2015

Giant water bug in pool skimmer

Jennifer Frazer in her Artful Amoeba Blog for Scientific American provides a good profile on the opportunistic assassin known commonly as the Giant water bug.  This insect was found in my pool skimmer basket this summer 2015.  I found a smaller juvenile water bug later this summer.  The bite of this insect can be painful and caution is advised when handling them. 

Giant water bugs (Belostomatidae family) Lethocerus americanus are attracted to lights.  It's amazing that an insect 4 inches in length can fly. During my youth I saw one in my front yard in at my house and added it to my 4-H entomology collection .   There was no water around so it appeared to be out of place.  More information is available from the Texas Master Gardner's Beneficial insect page.

Giant Water Bug life cycle - 1 min.

Saturday, August 8, 2015

Mycoremediation with Tradd Cotter

I listened recently to a Scott Mann's podcast interview of Tradd Cotter on Mushroom cultivation and mycoremediation.  Thanks to Bryan S. for the referral.  He talked about his book, Organic Mushroom Farming and Mycoremediation: Simple to Advanced and Experimental Techniques for Indoor and Outdoor Cultivation.

The book covers a wide range of information useful both to gardener's, researchers, lab set up and commercial mushroom production.  Tradd does his own media preparation, and provides recipes, building your own laminar flow cabinets.   He is a proponent of know than go.  He takes lab research and immediately translate it to information that is immediately accessible to people interested into mushroom cultivation.  He attempts to take the intimidation out of the process.

He also provides information using mushrooms to aid in water filtration in third world countries.  He is very interested in open source sharing of information to help better others and add to their body of knowledge at Mushroom Mountain in Greenville South Carolina.

TedX Greenville - Cultivating a Peace of mind - 16 minutes

Saturday, August 1, 2015

METPHAST Program - Occupational Health and Safety with Nano materials

Occupational Health and Safety training on emerging technology is developed jointly by the University of Minnesota, the University of Iowa and Dakota County Technical college.

Peter Raynor Introduction to the METPHAST program - 3 min and 30 seconds.

Individuals can sign up and register to view training videos at

Many of the training modules are still in production.  I am currently viewing the segment on aerosols.  The content is excellent and the quality of the video is very good. 

Friday, July 17, 2015

Craguns July 13, 2015 storm damage photos part 2

Craguns beach path - N.Carlson - click to enlarge
Picnic area by beach cabins at Craguns - N. Carlson
Downed power lines at Craguns - N. Carlson
Hungry Gull Restaurant roof damage on right. - N. Carlson
Fallen trees on road to cabin at Craguns - N. Carlson
Outdoor pool and Hungry Gull restaurant - N. Carlson

Brainerd Area Severe Weather July 12, 2015 - Craguns Damage

Craguns storm damage photo taken am July 13, 2015 - N. Carlson- Click to enlarge
Just after 6:30 pm on July 12, 2015 a series of storm cells (4 unconfirmed tornadoes - thought to be straight line winds) passed through several Gull Lake Resorts near Baxter and Brainerd, Minnesota.  Our family stayed in the cabin on the left in this photo at Craguns.  We had the option of parking at the precise location of the downed tree but decided to park in an open grassy area.  The damage to the neighbors truck in the middle was minimal.  The tree limb penetrated the cabin roof allowing rainwater and insulation to cover their beds.  They pulled the driest mattress out of the bedroom and slept on the living room floor.

As of yesterday, no one was injured in the storm.  This may be due to a couple of factors.  The storm hit while people were having supper.  Weather alert apps on smart phones let people know about tornadoes.  I was looking at the radar image while we were eating and noted what appeared to be a hook echo on the radar.  One minute later, my cellphone and the building's weather alert system sounded an alarm.  The staff ushered us down to the designated shelter area in the lower part of the building.  It was a hallway with no windows to the outside.  Power to the building went out and people begin using the flashlight apps on the cellphones.  Craguns' emergency generators were damaged in the storm so we continued to be without power.

We were down there for over an hour as the severe weather passed.  Staff provided people with ice water and found a room with chairs for individuals who could not stand.  Two guitar players kept us entertained with songs.

Before darkness set in, we chose to travel back to our cabin through a maze of downed trees and power lines using the light from the flashlight app on the cell phones.  The road to the resort was blocked with multiple downed trees and power lines. Workers with chainsaws begin clearing the trees by the light from truck headlights.

Vehicles undamaged July 13, 2015 am. - N. Carlson
Two members of our family had fallen trees near their vehicles near downed power lines and we were not able to assess the damage until morning.  Damaged turned out to be minimal.  At the cabin the plumbing did not work and we were instructed not to flush the toilets.  We ended up using lake water to fill the tank in our toilets. We went to sleep listening to the sound of chainsaws.  Later in the evening we listened to the bullfrogs croaking in the nearby wetland.

Damage to a deck down the beach from our cabin - N. Carlson
The following morning we surveyed the damage to the resort. Damage to the buildings on the property turned out to be less than expected. Many cars were damaged including some late model Ford vehicles.  We drank bottled water and minimized the number of times we opened the refrigerator.

Downed trees at the top of a hill near the Hungry Gull Restaurant - N. Carlson
Craguns gave guests evacuation orders as they had no electricity and no working plumbing.  The grounds were also covered with debris, partially downed trees and power lines on the ground.

Main road into Craguns - The road on the left was blocked by downed power lines

We left before noon driving on a narrow pathway of freshly cut trees.  The final part of our road was blocked with power lines so we drove on grass for less than 50 feet before exiting on the main road out of the resort.  We hope to come back after they complete repairs.  According to the owner, Dutch Cragun, this is the first tornado that they have experienced in 74 years.

Lessons learned:
  1. Keep smart phones charged and with you during potential severe weather.  I used both my work and personal phone for flashlights and to keep track of the weather.
  2. Keep ice packs in the freezer for use later in portable coolers. 
  3. Keep bottled water on hand for drinking and hygiene. 
  4. If possible, avoid parking close to trees during a severe weather event. 
  5. Take shelter away from windows in a storm. 
  6. Heed evacuation orders to allow repairs to be completed safely and efficiently.

Video from a 1991 Gull Lake tornado-  This illustrates why you stay away from windows.

Saturday, June 27, 2015

Cottonwood seeds vs AC condenser unit

My air conditioning condenser unit coated with cottonwood seeds June, 2015
My air conditioning unit no longer maintained proper temperature in the house.  It ran constantly but did not lower the temperature.   I noted more noise from the condenser unit. I shut off power to the condensing unit.

1/2 dirty and 1/2 clean unit

Cleaning with a soft bristle brush

Heavy levels of cottonwood seeds plugged the condenser.  I cleaned it with a soft bristle brush.  I finished tightening all the metal screen screws the next morning as the mosquitoes were hungry. 

The house AC now works properly and uses less energy.  Similar problems with outside air filters happen during this time of the year.  This restricts the flow of air in building air systems.

Friday, June 12, 2015

Change ceiling fan rotation for Summer and Winter

Redirect ceiling fans (MN Chamber of Commerce): "Air conditioning often produces the highest electricity bill in a business or home, especially when it’s used consistently during the summer months. So a worthy goal is limiting your air conditioning use as much as possible. One way to avoid A/C use is using ceiling fans. In the winter months, ceiling fans should go clockwise to push rising warm air downward. In the summer, however, the fans should circulate counterclockwise for the opposite effect. It’s usually as easy as flipping a switch in the center of the fan."

Additional personal advice.  Clean the ceiling fan blades off each time you change the rotation. This keeps the fan blade dust from falling on the floor. My failure to do this resulted in a tedious cleanup.

Saturday, May 23, 2015

Salt water pool maintenance

Pool encounter Orca vs Mallard - N. Carlson

Backyard swimming pools are now using saltwater chlorination systems (wikipedia) to provide proper chlorination for the pools.  If properly designed the system maintains adequate chlorine levels while reducing the chloramine odors.  The salt concentration is typically in the range 2700 to 3400 ppm, although it may be higher in some systems. 

From an energy use standpoint: the salt water pools only work if the pump is operating allowing the chlorine to be generated from the salt solution.  A two speed pump can be used to keep the chlorine levels up while reducing energy consumption.   The salt used in the pool must be free of additives.

Hayword pools has an excellent guide to maintain proper salt water pool chemistry.

  1. Keep salt concentrations between 2,700 and 3,400 ppm.  This concentration may vary depending on the type of system.
  2. Adjust stabalizer - cyanuric acid levels to 60 - 80 ppm for an outdoor pool -  This reduces evaporation of chlorine from the pool
  3. Alkalinity - 80 - 120 ppm - Adjust by adding sodium bicarbonate
  4. Hardness 200 - 400 ppm - adjust by adding calcium chloride
  5. pH 7.4 to 7.8  - adjust up using soda ash (sodium carbonate)  adjust down using muriatic acid (HCL)
Keeping the cover on the pool also traps heat, reduces the amount of debris in the pool and helps maintain chlorine levels 

Thursday, May 21, 2015

High Tree pollen counts in the midwest

Photo micrograph of Oak/Maple pollen spores May 8, 2015 St. Paul MN - N. Carson - click to enlarge

There may be a reason that individuals with seasonal allergy/asthma are miserable.  Chicago station WLS reported that the Highest Tree Pollen Count in History Recorded for Midwest was noted by Dr. Joseph Leija on Friday May 1, 2015.  He measured 2,000 spores per cubic meter.

The last item piqued my interest and I check an Air-o-cell sample I took on May 8, 2013.  I measured 4,800 tree pollen per cubic meter of air on the St. Paul campus of the University of Minnesota.   Most of the pollen was either maple or oak.

Monday, May 11, 2015

Archimedes Death Ray

Ship set on fire by reflected mirrors

MIT experiment suggests that Archimedes could have set fire to Roman warships using focused reflected sunlight.  The experiment did not work well when oak was used.  When they used wood similar to cedar and under the proper light conditions with enough mirrors properly focused, the boat caught fire on top of a parking ramp.  Attempts to replicated this need to incorporate plenty of safety precautions. 

 Greenpower - 9 minutes

Healthy Home Tips by Jeffrey C. May and Connie L. May

The book, Jeff May's Healthy Home Tips: A Workbook for Detecting, Diagnosing, and Eliminating Pesky Pests, Stinky Stenches, Musty Mold, and Other Aggravating Home Problems, by husband and wife Jeffrey C. Man and Connie L. May provides a good series of checklist for home inspectors, new home buyers and home owners.  The playful banter between Connie and Jeff add to the books entertainment value and also increase the comprehension for some of the more technical discussions.

Approximately half the book is devoted to mold and water damage issues.  This ratio correlates fairly well with what I encounter during home and commercial building inspections.

Fungal growth and water damage on carpet tack strip - N. Carlson