Clo Values...What’s That?©

 

 

Humans originally come from the tropics and that is why we create artificial, tropical, microclimates in our homes, offices, cars and beneath the layers of clothes we wear.  And everyone knows that clothes keep you warm and protect you from the cold, but just how much protection do they provide?  That is the question that A.P. Gagge, A.C. Burton, and H.C. Brazett wanted to answer in the early 1940s.

 

So, they did the research, and in the November 7, 1941, edition of Science they published, “A Practical System of Units for the Description of the Heat Exchange of Man With His Environment” explaining what a “Clo Unit”, a measurement value that they had created, was.

 

Gagge et al., created the concept of the “Clo unit” to measure the thermal resistance of clothing, which was called “clothing insulation”.  They measured the insulation of clothing in “Clos” which shows the clothing’s, not of fabric’s, ability to prevent the transfer the body’s heat to the environment, and which considers the effect of air movement both inside clothing through body movement, and of wind outside the clothing.  A “Clo unit” as a value of clothing insulation can be used to gauge the effectiveness of clothing to maintain the body’s normal temperature and as an insulating protection from the environment. 

 

The factors that affect thermal comfort are air temperature, wind speed (convection), heat conduction from you to other objects, radiation from you or to you from other objects or heat sources, humidity, activity, and clothing.  Your clothing is the primary shelter protecting you from the environment by controlling the heat transfer from your body to the environment and vice versa.

 

The enclosed air layer trapped between your skin surface and the first layer of your clothing creates a microclimate that provides you, as a member of a tropical species, with the warmth necessary for your survival.  This microclimate is the air layer trapped nearest to your skin.  Although the factors stated above need to be considered, the measurement of clothing insulation, in “Clo”, offers a simple way to determine whether people feel comfortable in the clothing that they are wearing.

 

So, how warm are your clothes...

 

Your clothes work as a unit, and they can be layered to increase or decrease insulation you need.  Clothing provides insulation because of the low heat conduction of the air trapped within its layers.  The overall thickness of clothing is responsible for its insulation value, since as layers increase more areas of trapped air are created.  An overall thickness of 1 inch of clothing (2.5 cm) is considered to have an insulation value of approximately 4.0 clo.  However, the amount of insulation that is provided by adding extra layers of clothes is limited by the increasing restriction of movement caused by the bulk of the extra clothes.  In general, 1 inch to 1-½ inches (2.5 to 3.75 cm) has been accepted as the upper limit in thickness that can be easily worn.

 

The insulation, or clo value, of your clothing is decreased by moisture content trapped within it.  This is because wetting clothes reduces their ability to trap air.  The greater the moisture content, the less the insulating value of the clothing, and even a small amount of sweat will decrease the insulating value of your clothes.  This is why layers should be removed as activity increases or waterproof outer layers should be worn when wet weather conditions are experienced.

 

Also, when your clothes are compressed, either by wearing clothes that are too tight, by over-layering, or by wearing a pack, their insulation value will be reduced due to the compression of air layers trapped within them.  Additionally, sitting or lying down will reduce the clo value of your clothes.

 

Body motion and activity also reduces the insulation value of your clothes by pumping air through openings in your clothes and causing air movement within your clothing.  Wind also quickly diminishes the insulation value of your clothes by blowing away the layers of warmed air trapped inside your clothes, this is why a windproof/waterproof outer layer is so vital to staying warm.

 

So, that is how you know just how warm your clothes are and why layering and staying “comfortably cold” works, and it is all thanks to the research of A.P. Gagge, A.C. Burton, and H.C. Brazett and their “Clo unit”.

 

Don’t forget to come back next week and read “Burning Calories for Heat ©”, where we will talk about how your body creates the heat that your clothes trap close to your skin.

 

I hope that you continue to enjoy The Woodsman’s Journal Online and look for me on YouTube at BandanaMan Productions for other related videos, HERE.  Don’t forget to follow me on both The Woodsman’s Journal Online, HERE, and subscribe to BandanaMan Productions on YouTube.  If you have questions, as always, feel free to leave a comment on either site.  I announce new articles on Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at Eric Reynolds, so watch for me.

 

That is all for now, and as always, until next time, Happy Trails!

 

 

Sources

 

A.P. Gagge, A.C. Burton, and H.C. Brazett; “A Practical System of Units for the Description of the Heat Exchange of Man With His Environment”, Science, November 7 1941, Vol 94, Issue 2445, page 428-430, https://www.science.org/doi/10.1126/science.94.2445.428, accessed December 2, 2023

 

Auliciems, Andris; and Szokolay, Steven V.; Thermal Comfort, https://www.researchgate.net/publication/234169993_THERMAL_COMFORT/link/0fcfd50fd28d99989b000000/download, accessed December 2, 2023

 

Eisberg, Harry Belleville; Owens, J. E.; Fundamentals of Arctic and Cold Weather Medicine and Dentistry, [U.S. Navy Department, Washington, DC, 1949], https://books.google.com/books?id=2-bYnbMCwYQC&pg=PA80&dq=clo+values&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwjJtpavyMuCAxU0KlkFHWKIByYQ6AF6BAgFEAI#v=onepage&q=clo%20values&f=false

 

Kyunsoo, Lee; Haneul, Choi; Hyungkeun, Kim; Daeung, Kim Danny; and Kim, Taeyeon; “Assessment of a Real-Time Prediction Method for High Clothing Thermal Insulation Using a Thermoregulation Model and an Infrared Camera”, Atmosphere 2020, Vol. 11, No. 1, page 106, https://www.mdpi.com/2073-4433/11/1/106, accessed December 2, 2023

 

Lundgren, Peter; Björnstig, Ulf; Kuklane, Kalev; “Protection Against Cold in Prehospital Care -- Thermal Insulation, Properties of Blankets and Rescue Bags in Different Wind Conditions”, https://www.researchgate.net/figure/Thermal-insulation-clo-for-insulation-ensembles-in-the-low-insulation-group-at-low_fig2_40909134, accessed December 2, 2023

 

Roast; “Understanding CLO Values”,[© 2023 KT Innovations], https://roastsurvey.com/blog-post/understanding-clo-values/#:~:text=What%20Are%20CLO%20Values%3F,by%20an%20article%20of%20clothing.&text=A%20CLO%20value%20of%201,Celsius%2C%20or%2071%20degrees%20Fahrenheit, accessed December 2, 2023

 

A Walk in the Woods©

 

 

A “walk in the woods”, the Urban Dictionary¹ says that means “a big waste of time and effort, as in when a when a hunter comes back empty handed”.  I went on a walk in the woods at Chestnut Ridge Park the other weekend, but I didn’t think it was a big waste of time and effort!

 

The flame behind the falls was burning brightly, but it hadn’t rained recently, so the falls were dry, and it wasn’t very photogenic, but I did see some other cool things.

 

A big patch of partridge berries...

 

I found a big patch of partridgeberries (mitchella repens), with lots of ripe, bright red berries.  I knew that they were partridgeberries, not american winter green, because of the smooth-edged leaves, with the bright greenish-yellow leaf vein.

 

For more on partridge berries read “American Wintergreen or Partridgeberry? ... That is The Question©”, HERE.

 

A pawpaw tree...

 

I had never seen a pawpaw tree before, not because they are rare, although the Lake Erie shoreline is at the northern end of their range, but because their leaves resemble the leaves of the spicebush, shagbark hickory, white ash, and magnolia trees.  But just like oaks, beeches, and american chestnut trees, the leaves of pawpaw trees stay attached to their branches until late in the fall, so it is easier to identify them in the late fall than during the summer.

 

Pawpaw leaves are large and oval, and they alternate on the branch, they have smooth edges, and the trunks have bark that is mostly smooth, with a series of small, darker bumps on the bark.

 

An american chestnut tree...

 

Absolutely, the coolest thing that I found on my walk, was a living american chestnut, castanea dentata, tree!  It was only a small shoot growing from the roots of a tree that had died of chestnut blight fungus, cryphonectria parasitica, but it was alive!  The american chestnut is critically endangered, not extinct, because the blight infects and slowly kills the trunk of tree, leaving the roots alive.  This shoot is most likely a third generation sapling, growing from the existing root system of an original tree that had died from the blight in the early 1900s.

 

The american chestnut once grew to truly mammoth sizes, and now they are mostly gone, but several groups are working to find a way to make them resistant to the blight, so maybe someday they’ll be back, growing to their full gigantic size!

 

So, my walk in the woods wasn’t a big waste of time and effort, and I don’t think I came back empty handed, because I found some truly cool plants!

 

Don’t forget to come back next week and read “Clo Values...What? ©”, where we will talk about how warm clothes are and what to wear to stay comfortably cold in the winter outdoors.

 

I hope that you continue to enjoy The Woodsman’s Journal Online and look for me on YouTube at BandanaMan Productions for other related videos, HERE.  Don’t forget to follow me on both The Woodsman’s Journal Online, HERE, and subscribe to BandanaMan Productions on YouTube.  If you have questions, as always, feel free to leave a comment on either site.  I announce new articles on Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at Eric Reynolds, so watch for me.

 

That is all for now, and as always, until next time, Happy Trails!

 

 

Notes

 

1 “a walk in the woods -- When a hunter comes back empty handed.  The hunting isn't always for animals, and can mean an effort that didn't pay off. A big waste of time and effort” . HERE

 

Sources

 

Grow It, Build It, The Blog; “The Pawpaw Tree – A Guide To America’s Native Tropical Fruit”, [Copyright 2023], https://growitbuildit.com/pawpaw-tree-asimina-triloba/, accessed November 24, 2023

 

Immel, Diana, and Anderson, M. Kat; “PAWPAW Asimina triloba (L.) Dunale.”, [USDA NRCS Plant Guide], https://plants.usda.gov/DocumentLibrary/plantguide/pdf/cs_astr.pdf, accessed November 24, 2023

 

Ross, Kathy N.; “Memory of great forests – and hope for restoration American chestnuts once dominated Appalachian region's forests”, August 27 2022, [The Mountaineer] https://www.themountaineer.com/news/haywood_history/memory-of-great-forests-and-hope-for-restoration/article_b4995be6-249d-11ed-a0ca-ff700334e153.html, accessed November 25, 2023

 

USDA, “Asimina triloba (L.) Dunal.  pawpaw”, [USDA NRCS Plants], https://plants.usda.gov/home/plantProfile?symbol=ASTR, accessed November 24, 2023

 

Wikimedia; “A close-up of the gas-lit flame below Eternal Flame Falls in Chestnut Ridge Park, Orchard Park, NY”, by Mpmajewski, May 1 2009, https://commons.wikimedia.org/wiki/File:Eternal_flame_falls_7252.jpg, accessed November 25, 2023

 

Baking Bannock Bread for Thanksgiving©

 

 

Bannock, banique, ash cakes, damper... all are a variety of flat, quick breads, sometimes unleavened, and baked and eaten primarily in Australia, North and Central America, Scotland, and British Isles.  The word bannock derives from Gaelic bannach, which means “morsel”, and likely came from the Latin panis, which simply means bread.  It was a staple in the diets of the early settlers and fur traders in North America. 

 

Today is bannock most often made of flour from grains, such as oats, barley, or wheat, but historically, before Europeans, in North America it had been made with cattails, acorns, mosses, lichens and ferns and even black tree lichen!¹  Most Native American nations in have a version of bannock.  The Inuit call it palauga, the Mi’kmaq luskinikn, and the Ojibwe ba‘wezhiganag.²

 

Baking Bannock

 

The first rule about baking bannock is that there are no rules.  A review of the recipes shows a wide and wild variation in the ingredients, amounts of the ingredients and baking times and methods.  Practically any combination of flour and water and possibly some form of leavening agent, that can be baked, fried or deep-fried will work, although the final bread will vary in “eatability”.

 

In its most basic form, it is simply made of flour, water, and sometimes butter, fat, or lard is added.  Sour milk, salt and either baking soda, salteratus, ash-water, or simply hard wood ashes, were sometimes added as a leavening agent, and today sugar is often added, depending on the recipe.  Bannock is traditionally cooked by mixing the ingredients into a large, round biscuit and baking it in a frying pan, on a bannock board or hot stone, wrapped around a branch by the side of the fire³, or in the ashes of the fire, either wrapped in leaves or not at all.  Today, bannock is usually baked in the oven, making a heavy and dense bread, or fried, making a light and fluffy bread; or sometimes even deep-fried.

 

Richard Munn wrote that famed author and wilderness canoeist Sigurd Olson in a letter written in 1962 said that his recipe for bannock was good “...for four, depending on what else goes with it”. His recipe is:

 

Take a pound of flour (3 ¹/₃ cups or 454 grams) of flour.

If you are making oat, barley, or cornmeal bannocks, use one cup (140 grams) of wheat flour to two cups (280 grams) of cornmeal, oat, or barley flour.

Add a pinch of salt.

If you are making “damper” or unleavened bannocks, go to the mixing and baking instructions now.

Add 1 teaspoon (6 grams) of baking soda.

Saleratus, from Latin “sal æratus”, meaning “aerated salt” is potassium bicarbonate, was widely used in the 19th century.  One teaspoon of saleratus equals 1 1/4 teaspoons of baking soda; baking soda is sodium bicarbonate.  Pearlash (refined potash) is a crude potassium carbonate, as is made by soaking hard wood, fireplace ashes in water to make lye or ash water.⁴  Saleratus was twice efficient as pearlash, so you will need to double the amount of saleratus if you use pearlash⁵.

Mix in ¾ to 1 (187 to 250 ml) cup of water if you are making
“damper” or unleavened bannocks.  If you are making leavened bannocks, use the same amount of sour milk or buttermilk.  Either way, mix the liquid into the dry ingredients by making a well in the center of the dry ingredients and mixing in just enough to make a stiff dough.

You can make sour milk by leaving fresh milk out to ferment and sour in a warm place for a day, often near a stove.  Or you can make 1 cup (250 ml) sour milk for baking by adding 1 tbsp (15 ml) of vinegar or lemon juice and enough milk to equal 1 cup (250 ml).  Stir and let stand for 5 minutes before using.  This will give the right amount of acidity for the recipe.

Roll out the dough on a floured surface to form one large bannock about ½ inch (1 ¼ cm) thick and cut it in quarters.  Heat an ungreased griddle or frying pan until moderately hot and cook the bannocks slowly until browned on each side.  You can also roll it out to ¼ inch (about ³/₄ cm) thick for a thinner, more cracker like, bread.

 

If cooking over a fire you can prop your bannock board, your griddle, or a large flat stone beside the fire to cook from the top down.  You can also cook it on a griddle over coals from the bottom up.  Or you can bury it surrounded in a thick layer of hot ashes, wrapped in leaves or not, with hot coals both above and below it.⁶

 

Bannock is delicious and because it is a thick, heavy bread it is perfect for outdoors trips, since it won’t crush or crumble.  Take it to Ren-Fairs, take it on walks in the wilderness.  Serve it hot, spread on bacon grease or butter, maple syrup, honey, or cheese.  Eat it cold.  Eat it with soup, stew, or chili.  Or simply eat it hot with tea!

 

Don’t forget to come back next week and read “A Walk in the Park ©”, where we will talk about the different things you can see on a walk in the park.

 

I hope that you continue to enjoy The Woodsman’s Journal Online and look for me on YouTube at BandanaMan Productions for other related videos, HERE.  Don’t forget to follow me on both The Woodsman’s Journal Online, HERE, and subscribe to BandanaMan Productions on YouTube.  If you have questions, as always, feel free to leave a comment on either site.  I announce new articles on Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at Eric Reynolds, so watch for me.

 

That is all for now, and as always, until next time, Happy Trails!

 

 

Notes

 

¹ “Bannock – First Nations Style”, by Shawn

 

² “Bannock”, The Canadian Encyclopedia, by John Robert Colombo, updated by Brad Dunne

 

³ “The ideal stick is fairly straight and made of non-poisonous hardwood that will not impart a disagreeable taste; good choices include branches of birch, hazel, or willow trees.  The bark should be whittled away from the branch 15–20 cm in from the end, where the dough will be wrapped.  The length depends on one's comfort and the fire's size.  The thickness of the bread-holding end is around 1.5–2 cm.  The thicker the stick, the heavier it is and thus the harder it is to hold.  However, a branch that is too thin will bend under its own weight if it is freshly cut”.

 

From Wikipedia, “Twist bread”, originally from “DANISH BONFIRE BREAD (SNOBRØD)”, HERE

 

⁴ For more information see “Victorian Baking: Saleratus, Baking Soda, and Salsoda”, by Kristin Holt.

 

⁵ See “Baking with Wood Ash? (Part 1)”, by Leigh

 

⁶ For more read “Cooking Ash Cakes”, Jennifer Stanley

 

Sources

 

Colombo, John Robert; updated by Dunne, Brad; “Bannock”, The Canadian Encyclopedia, February 6, 2006, https://www.thecanadianencyclopedia.ca/en/article/bannock, accessed November 18, 2023

 

Holt, Kristin; “Victorian Baking: Saleratus, Baking Soda, and Salsoda”, December 30, 2017; https://www.kristinholt.com/archives/13983, accessed November 18, 2023

 

Jamieson, John, D.D.; Etymological Dictionary of the Scottish Language, [Edinburgh, University Press, 1808], “BAN to BAN”, https://www.google.com/books/edition/An_Etymological_Dictionary_of_the_Scotti/H6AmAQAAIAAJ?hl=en&gbpv=1&dq=bannock&pg=PP149&printsec=frontcover, accessed November 18, 2023

 

Leigh; “Baking with Wood Ash? (Part 1)”, https://www.5acresandadream.com/2016/01/baking-with-wood-ash-part-1.html, accessed November 18, 2023

 

Leigh; “Baking with Wood Ash? (Part 2)”, https://www.5acresandadream.com/2016/01/baking-with-wood-ash-part-2.html, accessed November 18, 2023

 

Leigh; “Baking with Wood Ash? (Part 3)”, https://www.5acresandadream.com/2016/01/baking-with-wood-ash-part-3-results.html, accessed November 18, 2023

 

Munn, Richard; “Bannock 101”, July 12, 2006, https://www.myccr.com/articles/bannock-101, accessed November 18, 2023

 

Shawn; “Bannock – First Nations Style”, May 6, 2015, [© Eat], https://www.eatdrinkbreathe.com/bannock-first-nations-style/, accessed November 18, 2023

 

Stanley, Jennifer; “Cooking Ash Cakes”, Savoring the Past, [Jas. Townsend & Son, Inc.], https://savoringthepast.net/2016/03/20/cooking-ash-cakes/, accessed November 18, 2023

 

Wikimedia; “Making Oat Cakes”, by George Walker, 1814, https://commons.wikimedia.org/wiki/File:Making_oat_cakes_-_The_costume_of_Yorkshire_(1814),_plate_IX,_opposite_21_-_BL.jpg, accessed November 18, 2023

 

Wikipedia; “Twist bread”, https://en.wikipedia.org/wiki/Twist_bread, accessed November 18, 2023

 

Wikimedia; “Tea and Damper” by Alfred Martin Ebsworth, 1883, https://en.m.wikipedia.org/wiki/File:Tea_and_damper.jpg, accessed November 18, 2023