Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?



Brands, places, prices?


THANKS!


David

David Combs wrote:
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?



Brands, places, prices?


THANKS!


David

TSC tractor stores are great for outdoor work gear.

A brand name to look for online etc- carhartt

http://www.carhartt.com/

Dave

In article , (David Combs) wrote:

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.

A human body is not sufficiently warmer than its environment to lose much heat
by radiation. The overwhelming majority of heat loss from a human body is by
the evaporation of water from the skin and mucous membranes (including the
lungs), and by conduction to the air. Any heat lost conductively to free air
is rapidly removed convectively. The key to staying warm is to reduce this
convective loss by dressing in layers, to ensure that the warm air layer next
to the skin _stays_there_ instead of transporting that heat somewhere else.

Bottom line: anything that's reasonably well insulated, with a barrier to keep
out wind, will keep you warm. When I'm deer hunting, I wear coveralls
insulated with Thinsulate Ultra, and they keep me *very* warm -- despite the
fact that deer hunting in the Midwest is a largely sedentary activity that
consists mostly of sitting in a stand waiting for deer. You'll presumably be
active while wearing work pants, so your need for insulation is
correspondingly less than mine. My hunting coveralls are made by Walls; I
don't know if they make outdoor work clothing too, but most manufacturers of
hunting clothing do.

Try searching at cabelas.com or basspro.com

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

TSC stores carr Tough Duck "Work wear" it's what I'll be wearing for the
enxt few years or until soemthing better comes along. I have a set of
insulated and uninsalted and I rarely get the chance to wear the insulated
ones since they are to warm. Worth every penny I spent.


"David Combs" wrote in message
...
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?



Brands, places, prices?


THANKS!


David

"David Combs" wrote in message
...

QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

In Canada, you can buy cotton canvas work
pants lined with traditional type flannel, and
add wool long johns for cold days, ice fishing, etc.

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)

David Combs wrote:
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?



Brands, places, prices?


THANKS!


David


David-

As another posted suggested

carhartt, sturdy work clothes

http://www.carhartt.com/webapp/wcs/s...atalogId=10101

http://www.carhartt.com/webapp/wcs/s...tegoryId=10908

They make lots of different styles because it depends on the person,
what you're doing; how much mobility you want & the weather conditions

You can keep yourself warm with enough layers of any clothing but if
you're wrapped up like the Michelin tire man...it's gonna be hard to
move effectively

YEARS ago I had occasion to work outside in Ohio near the lake (luckily
I was younger then) I used insulated overalls (bib style) with long
underwear (uppers only) & a lighter jacket to mantain upper body
mobility.

I doubt I could stand that setup now but it worked great for me, back
then

Full insulated overalls can be a good choice but if you've got to
integrate fall protection into the setup....it leads back to bib
overalls w/ long jonhn shirt & another outer shirt. JMHO

In mountain areas (fall/ early winter) of California the guys seem to
settle on bib overalls & long sleeve pullover shirts (& of course, hard
hats & harness)

The concept is...keep the legs & trunk warm (feet too with insulated
boots or regular boots oversized for thick socks.)

........the arms will get warmed by circulation

If the weather gets colder or windy they add some sort of knit ski type
"helmet" under their hard hats

I use a........

http://gear-west.stores.yahoo.net/tufurfrma.html

keeps the bald spot on the top of my head from shedding all my heat



you low level activity standing, walking, sitting outdoors

a Polarwarp heat exchange mask

http://workingperson.com/products/85...Mask_FHCB.html

has some value but if you're really exerting yourself..IMO it's too
restrictive for adequate breathing

here are some "test drive" reports

http://www.backpackgeartest.org/revi...p%20Exchanger/

hth

cheers
Bob

Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Nick

In article , wrote:
Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , (Doug Miller) wrote:
re else.

Bottom line: anything that's reasonably well insulated, with a barrier to keep
out wind, will keep you warm. When I'm deer hunting, I wear coveralls
insulated with Thinsulate Ultra, and they keep me *very* warm -- despite the
fact that deer hunting in the Midwest is a largely sedentary activity that
consists mostly of sitting in a stand waiting for deer. You'll presumably be
active while wearing work pants, so your need for insulation is
correspondingly less than mine. My hunting coveralls are made by Walls; I
don't know if they make outdoor work clothing too, but most manufacturers of
hunting clothing do.

Try searching at cabelas.com or basspro.com

Update -- Walls definitely *does* make insulated work wear. I just saw a guy
wearing some when I picked up some building supplies this afternoon.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

wrote:
Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Nick


A cold clear night is even better

cheers
Bob

Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

Nick

In article , (Nick Pine) wrote:
Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

David Combs wrote:
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

I live in the north country and always buy Carhardtt brand. there are
many imitators that do a good job, however. I have a lot of carhardtt
stuff and swear by it. They offer pants, overalls, coveralls, and
shirts in both unlined and quilted versions. they are not cheap but
are the best. They are the most rugged work clothes ever. It is
possible to wear out a pair of Carhartts, but not easy. Most of
their work clothes are union made in the USA. I buy mine online at:

http://www.getzs.com/store/customer/home.php

They have the complete line and have been reliable for me. Don't know
about where you live but around here Fleet Farm is the local source for
Carhardtt. Other outdoor stores like Cabelas and Gander Mountain also
stock it.

Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Got numbers?

Nick

In article , wrote:
Doug Miller wrote:

A human body is not sufficiently warmer than its environment to lose
much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Got numbers?

Get your own numbers.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

wrote in
:

Doug Miller wrote:

A human body is not sufficiently warmer than its environment to
lose much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Got numbers?

Nick


6
27
1986
-22
55.8
|-500|

all numbers =0
all numbers 0

That should cover it pretty much.

I'm from Canada and had spent twelve years working above the arctic circle.
You can forget about the designer stuff...buy Carhardtt brand. Jim

David Combs wrote:
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

Carhardtt makes jeans that are very durable, available at Sears and
Roebuck, Tractor Supply and a lot of other places.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?

I live in Florida now, but back in the "cold days," as a construction
electrician, working right beside steel workers in the Midwest, here's
what I used to wear:

Regular underwear ^ long johns ^ heavy socks ^ Uninsulated Carhardtt
jeans, or regular jeans ^ heavy flannel shirt ^ zippered, lined,
sweatshirt with hood ^ Insulated Carhardtt bib overalls (for better
movement) ^ Carhardt insulated jacket with hood ^ sock hat ^ work boots
^ slip over rubber boots ^ cotton gloves under deerskin gloves.
Everything slightly loose. In my case, doing electrical work,
everything needed to be 100% cotton and Carhardtt wool linings, no
plastic....something that is hard to find these days.

All that, and the coldest I've ever been, including living in Norway
for 3 years, was right here in Florida....doing some wiring inside of a
minus 40 degree F cold storage facility. Just had a winter jacket too.


The trick to staying warm is wearing slightly loose, layered clothing
and don't get wet.....even from sweating. If you start to sweat,
unzip, unbutton, or take off some clothing and go back to work until
you start to feel cold again, then put cloths back on as needed. On
sunny days sometimes I could strip down to just the flannel shirt and
bibs for 10 minutes or so. The rubber boots go a long way to keeping
your feet warm and dry. Once your feet get wet, you're screwed.

volts500 wrote:
David Combs wrote:
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

Carhardtt makes jeans that are very durable, available at Sears and
Roebuck, Tractor Supply and a lot of other places.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.
I work outside all winter in Minnesota, and here's my philosophy:

I wear arctic wt. carhart bibs when it is below zero. otherwise I wear
a pair of oversized jeans or light wool pants over fleece sweat pants.
I can't imagine wearing all cotton. I go to secondhand stores and buy
wool sweaters and coats which I wear in layers depending on the temp.
I did go out and spent 60 bucks on a merino wool underwear shirt which
was worth every penny. sweating or a little rain or snow is no problem
with wool.

Al Bundy wrote:
wrote in
Doug Miller wrote:

A human body is not sufficiently warmer than its environment to
lose much heat by radiation...

It is, on a cold clear day.

Not in comparison to the heat lost through evaporation and
conduction/convection. Not even close.

I disagree. Got numbers?

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Got numbers?

6
27
1986
-22
55.8
|-500|

all numbers =0
all numbers 0

That should cover it pretty much.

Makes as much sense as Doug's reply :-)

Nick

In article , wrote:

Makes as much sense as Doug's reply :-)

It's not *my* job to remedy deficiencies in *your* education.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Doug Miller wrote:

It's not *my* job to remedy deficiencies in *your* education.

Nor mine. So far, we merely have two different opinions. YOU made a claim,
and I invited you to justify it.

Nick

Look up

Carhart
Dickies
Skillers
Duluth
___________________________
Keep the whole world singing. . . .
DanG


"David Combs" wrote in message
...
Am looking for heavy-duty **warm** work-pants, and can't
so far find much somewhat near the top of a google search.

Years and years (30?) ago I bought such a pair, outside
made of something strong, like canvas, maybe, with a quilted
semi-sweat-impermeable-covered thickish lining.

So tough that I probably could have walked through a
patch of catclaw without tearing it.

And WARM.

Partly due to the lining, and partly (or mainly?) due to
the *weight* of the material, which helps lower *radiative*
heat loss.

These days, however, I seem to find only cheap, thin stuff,
(easy to tear, wear holes into, etc)
and if with lining, then only with "fleece", which in my
experience will stretch and of course provides a ZERO
*radiative* heat-loss barrier.


QUESTION: In northern Minnesota or Alaska, say, what do
outdoor workers wear?

Or steel-workers 50 stories up, with wind-chill at -30 --
what do *they* wear?



Brands, places, prices?


THANKS!


David

In article , wrote:
Doug Miller wrote:

It's not *my* job to remedy deficiencies in *your* education.

Nor mine. So far, we merely have two different opinions. YOU made a claim,
and I invited you to justify it.

Actually, remedying deficiencies in your education *is* your responsibility.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Doug Miller wrote:

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Here's how I figure it:

20 TDB=-2.2'average daily min temp in January in Duluth (F)
30 TDBC=(TDB-32)/1.8'dry bulb temp (C)
40 V=11.6'windspeed (mph)
50 W=.0012'average humidity ratio
60 PA=29.921/(1+.62198/W)'vapor pressure ("Hg)
70 E=3.3772*PA'vapor pressure (kPa)
80 TDP=9621/(17.863-LOG(PA))-460'dew point temp (F)
90 IF TDPTDB THEN TDP=TDB
100 TDPC=(TDP-32)/1.8'dew point temp (C)
110 GAMMA=.00066*101.325'constant for wet bulb temp calc
120 TDC=(TWBEC+TDPC)/2
130 DELTA=4098*E/(TDC+237.3)^2
140 TWBC=(GAMMA*TDBC+DELTA*TDC)/(GAMMA+DELTA)'wet bulb estimate (C)
150 IF ABS(TWBC-TWBEC).01 THEN TWBEC=TWBC:GOTO 120'iterate to 0.01 C
160 TWB=1.8*TWBC+32'wet bulb temp (F)
170 IF TWBTDB THEN TWB=TDB
180 A=.002056*TDP+.7378'coefficient in Niles equations
190 TS=92'skin temp (F)
200 QR=1.63E-09*((TS+460)^4-A*(TDB+460)^4)'radiation loss (Btu/h-ft^2)
210 QC=(.74+.3*V)*(TS-TDB)'convection loss (Btu/h-ft^2)
220 B=3.01*(.74+.3*V)*((TS+TWB)/65-1)
230 QE=B*(TS-TWB)-QC'evaporation loss (Btu/h-ft^2)
240 PRINT TDB,TWB,TDP
250 PRINT QR,QC,QE

dry bulb wet bulb dew point

-2.2 -2.2 -2.2 F

radiation convection evaporation

98.83666 397.524 59.00485 Btu/h-ft^2

NREL's V = 11.6 mph in line 40 was probably measured at an airport.
Changing to V = 0 lowers convection to 70 and evaporation to 10,
so radiation loss dominates.

NREL's 24-hour average humidity ratio makes the wet bulb and dew points
higher than the dry bulb, which probably means there's frost on
an average January night, which might warm you up.

Thanks for the "education" :-)

Nick

wrote:
Doug Miller wrote:

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Here's how I figure it:

20 TDB=-2.2'average daily min temp in January in Duluth (F)
30 TDBC=(TDB-32)/1.8'dry bulb temp (C)
40 V=11.6'windspeed (mph)
50 W=.0012'average humidity ratio
60 PA=29.921/(1+.62198/W)'vapor pressure ("Hg)
70 E=3.3772*PA'vapor pressure (kPa)
80 TDP=9621/(17.863-LOG(PA))-460'dew point temp (F)
90 IF TDPTDB THEN TDP=TDB
100 TDPC=(TDP-32)/1.8'dew point temp (C)
110 GAMMA=.00066*101.325'constant for wet bulb temp calc
120 TDC=(TWBEC+TDPC)/2
130 DELTA=4098*E/(TDC+237.3)^2
140 TWBC=(GAMMA*TDBC+DELTA*TDC)/(GAMMA+DELTA)'wet bulb estimate (C)
150 IF ABS(TWBC-TWBEC).01 THEN TWBEC=TWBC:GOTO 120'iterate to 0.01 C
160 TWB=1.8*TWBC+32'wet bulb temp (F)
170 IF TWBTDB THEN TWB=TDB
180 A=.002056*TDP+.7378'coefficient in Niles equations
190 TS=92'skin temp (F)
200 QR=1.63E-09*((TS+460)^4-A*(TDB+460)^4)'radiation loss (Btu/h-ft^2)
210 QC=(.74+.3*V)*(TS-TDB)'convection loss (Btu/h-ft^2)
220 B=3.01*(.74+.3*V)*((TS+TWB)/65-1)
230 QE=B*(TS-TWB)-QC'evaporation loss (Btu/h-ft^2)
240 PRINT TDB,TWB,TDP
250 PRINT QR,QC,QE

dry bulb wet bulb dew point

-2.2 -2.2 -2.2 F

radiation convection evaporation

98.83666 397.524 59.00485 Btu/h-ft^2

NREL's V = 11.6 mph in line 40 was probably measured at an airport.
Changing to V = 0 lowers convection to 70 and evaporation to 10,
so radiation loss dominates.

NREL's 24-hour average humidity ratio makes the wet bulb and dew points
higher than the dry bulb, which probably means there's frost on
an average January night, which might warm you up.

Thanks for the "education" :-)

Nick


Heat transfer by radiation for bare skin?
What about the effect of clothing on radiation efficiency?

Won't your "TS" be much closer to air temp than body temp?

Or we're you just looking for SWAG on bare skin Q as a starting point?

In any case, for properly clothed human in a cold environment, QR
looks to be pretty low compared to other mechanisms

cheers
Bob

cheers

wrote:
Doug Miller wrote:

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Here's how I figure it:

....

190 TS=92'skin temp (F)
200 QR=1.63E-09*((TS+460)^4-A*(TDB+460)^4)'radiation loss (Btu/h-ft^2)
.....

But one would assume you're not going to be standing out directly as a
radiative body. The outer layer trying to radiate to the environment
won't be but a few degrees warmer than the ambient, certainly nothing
even remotely close to 90F.

wrote:
Doug Miller wrote:

In general, radiation is about an order of magnitude less effective at
transferring heat than conduction or convection.

Here's how I figure it:

20 TDB=-2.2'average daily min temp in January in Duluth (F)
30 TDBC=(TDB-32)/1.8'dry bulb temp (C)
40 V=11.6'windspeed (mph)
50 W=.0012'average humidity ratio
60 PA=29.921/(1+.62198/W)'vapor pressure ("Hg)
70 E=3.3772*PA'vapor pressure (kPa)
80 TDP=9621/(17.863-LOG(PA))-460'dew point temp (F)
90 IF TDPTDB THEN TDP=TDB
100 TDPC=(TDP-32)/1.8'dew point temp (C)
110 GAMMA=.00066*101.325'constant for wet bulb temp calc
120 TDC=(TWBEC+TDPC)/2
130 DELTA=4098*E/(TDC+237.3)^2
140 TWBC=(GAMMA*TDBC+DELTA*TDC)/(GAMMA+DELTA)'wet bulb estimate (C)
150 IF ABS(TWBC-TWBEC).01 THEN TWBEC=TWBC:GOTO 120'iterate to 0.01 C
160 TWB=1.8*TWBC+32'wet bulb temp (F)
170 IF TWBTDB THEN TWB=TDB
180 A=.002056*TDP+.7378'coefficient in Niles equations
190 TS=92'skin temp (F)
200 QR=1.63E-09*((TS+460)^4-A*(TDB+460)^4)'radiation loss (Btu/h-ft^2)
210 QC=(.74+.3*V)*(TS-TDB)'convection loss (Btu/h-ft^2)
220 B=3.01*(.74+.3*V)*((TS+TWB)/65-1)
230 QE=B*(TS-TWB)-QC'evaporation loss (Btu/h-ft^2)
240 PRINT TDB,TWB,TDP
250 PRINT QR,QC,QE

dry bulb wet bulb dew point

-2.2 -2.2 -2.2 F

radiation convection evaporation

98.83666 397.524 59.00485 Btu/h-ft^2

NREL's V = 11.6 mph in line 40 was probably measured at an airport.
Changing to V = 0 lowers convection to 70 and evaporation to 10,
so radiation loss dominates.

NREL's 24-hour average humidity ratio makes the wet bulb and dew points
higher than the dry bulb, which probably means there's frost on
an average January night, which might warm you up.

Thanks for the "education" :-)

Nick


Heat transfer by radiation for bare skin?
What about the effect of clothing on radiation efficiency?

Or we're you just looking for SWAG on bare skin Q as a starting point?

In any case, for properly clothed human in a cold environment, QR
looks to be pretty low compared to other mechanisms

cheers
Bob

PS for everyone's information, here is a qualitative article about
heat loss (while outdoors, low, moderate & heavy exertion levels)
hiking & backpacking related but IMO applicable to working outside as
well

bottomline of the article ......QR generally very low in comparison
except when person is inactive (esp at night) in a windless
condition...then QR remains where heat loss by other means have fallen.

SO...wrt to keeping warm while "working" QR is not importatnt unless
our subject's job involves sleeping outside. (at night)

radiation convection evaporation

98.83666 397.524 59.00485 Btu/h-ft^2

NREL's V = 11.6 mph in line 40 was probably measured at an airport.
Changing to V = 0 lowers convection to 70 and evaporation to 10,
so radiation loss dominates.

NREL's 24-hour average humidity ratio makes the wet bulb and dew points
higher than the dry bulb, which probably means there's frost on
an average January night, which might warm you up.

Heat transfer by radiation for bare skin?

Yes. Clothing lowers the losses.

Won't your "TS" be much closer to air temp than body temp?

Maybe. I measured 92 F in a 70 F room.

Nick

Thanks to all for the WONDERFUL replies!

What a super group this is!

David