Question:
The ASHRAE 55-2004 comfort standard (based on worldwide surveys of 21,000 people) defines the winter and summer comfort zones below with equal air and wall temperatures, equal human activity levels, and a fixed 0.1 m/s air velocity: T (F) RH clo PMV PPD 67.3 86 1 -.4778556 9.769089 75.0 66 1 .4732535 9.676994 78.3 15 1 .5239881 10.74283 70.2 20 1 -.4779105 9.770202 74.5 67 .5 -.4747404 9.706658 80.2 56 .5 .5145492 10.53611 82.2 13 .5 .5003051 10.23146 76.5 16 .5 -.4883473 9.982468 The winter zone assumes heavier clothing with more thermal resistance (clo=1), and the summer zone assumes lighter clothing (clo=0.5). The zones are defined by a +/- 0.5 score on a "Predicted Mean Vote" comfort scale that varies from -3 (very cold) to +3 (very warm.) The 4 corners of each zone are based on high and low temperatures and humidities. The "Percentage of People Dissatisfied" (PPD) score is based on the PMV. Even with PMV = 0 ("comfortable"), about 6% of the people are dissatisfied… If people are willing to change clothing more than twice a year (early PA farmers had one set of clothes for work and another for church, and washed them twice a year, when they also took baths 
and we vary air velocity with a ceiling fan, these zones can be expanded, which can make a solar house or one heated and cooled with the help of a whole-house fan more efficient. We can also raise the upper comfort temperature limit in air with lower humidity, and vice versa. The ASHRAE 55-2004 standard contains a BASIC program to help do this. Here are some calculations based on NREL’s long-term December and August weather averages for San Diego: 20 CLO = 1′clothing insulation (clo) 30 MET=1.1′metabolic rate (met) 40 WME=0′external work (met) 50 TA=19.6′air temp (C) 60 TR=19.6′mean radiant temp (C) 70 VEL=.1′air velocity 80 RH=0′relative humidity (%) 90 DATA 68.8,0.0062,0.05,1 100 DATA 83.9,0.0062,0.5,0.5 110 DATA 67.1,0.0121,0.05,1 120 DATA 82.9,0.0121,0.5,0.5 130 FOR CASE = 1 TO 4 140 READ TC,WA,VEL,CLO 145 TA=(TC-32)/1.8′air temp (C) 146 TR=TA’mean radiant temp (C) 150 PA=29.921*3377.2/(1+.62198/WA)’water vapor pressure (Pa) 160 DEF FNPS(T)=EXP(16.6536-4030.183/(TA+235))’sat vapor pressure, kPa 170 IF PA=0 THEN PA=RH*10*FNPS(TA)’water vapor pressure, Pa 180 ICL=.155*CLO’clothing resistance (m^2K/W) 190 M=MET*58.15′metabolic rate (W/m^2) 200 W=WME*58.15′external work in (W/m^2) 210 MW=M-W’internal heat production 220 IF ICL<.078 THEN FCL=1+1.29*ICL ELSE FCL=1.05+.645*ICL’clothing factor 230 HCF=12.1*SQR(VEL)’forced convection conductance 240 TAA=TA+273′air temp (K) 250 TRA=TR+273′mean radiant temp (K) 260 TCLA=TAA+(35.5-TA)/(3.5*(6.45*ICL+.1))’est clothing temp 270 P1=ICL*FCL:P2=P1*3.96:P3=P1*100:P4=P1*TAA’intermediate values 280 P5=308.7-.028*MW+P2*(TRA/100)^4 290 XN=TCLA/100 300 XF=XN 310 N=0′number of iterations 320 EPS=.00015’stop iteration when met 330 XF=(XF+XN)/2′natural convection conductance 340 HCN=2.38*ABS(100*XF-TAA)^.25 350 IF HCF>HCN THEN HC=HCF ELSE HC=HCN 360 XN=(P5+P4*HC-P2*XF^4)/(100+P3*HC) 370 N=N+1 380 IF N>150 GOTO 500 390 IF ABS(XN-XF)>EPS GOTO 330 400 TCL=100*XN-273′clothing surface temp (C) 410 HL1=.00305*(5733-6.99*MW-PA)’heat loss diff through skin 420 IF MW>58.15 THEN HL2=.42*(MW-58.15) ELSE HL2=0′heat loss by sweating 430 HL3=.000017*M*(5867-PA)’latent respiration heat loss 440 HL4=.0014*M*(34-TA)’dry respiration heat loss 450 HL5=3.96*FCL*(XN^4-(TRA/100)^4)’heat loss by radiation 460 HL6=FCL*HC*(TCL-TA)’heat loss by convection 470 TS=.303*EXP(-.036*M)+.028′thermal sensation transfer coefficient 480 PMV=TS*(MW-HL1-HL2-HL3-HL4-HL5-HL6)’predicted mean vote 490 GOTO 510 500 PMV=99999!:PPD=100 510 PRINT TC,WA,VEL,CLO,PMV 520 NEXT CASE Dry bulb Humidity Air vel. Clothing Predicted mean temp (F) ratio (m/s) (Clo) vote (PMV) 68.8 .0062 .05 1 -.4997552 83.9 .0062 .5 .5 .4852427 67.1 .0121 .05 1 -.491671 82.9 .0121 .5 .5 .4890098 NREL says average daily highs and lows are 48.8 and 66.1 F with w = 0.0062 pounds of water per pound of dry air in December and 67.3 and 77.8 with w = 0.0121 in August. An airtight well-insulated house with thermal mass and internal heat gain and a smart whole-house fan controller would barely need heating or cooling all year. Architects call this "thermal sailing." With inexpensive solar heating and whole-house fan heating and cooling, it would be more efficient to make the house air temperature closer to the upper comfort limit on an average winter day and closer to the lower comfort limit on an average summer day, in order to store lots of thermal energy in the mass of a house. A mean radiant (wall) temp that’s less than the house air temp in winter and greater in summer would allow raising the upper winter air comfort temp limit and lowering the lower summer air comfort temp limit. Occupants might also vary activity levels and wear clothing with more or less resistance, eg a sweater as well as a long- sleeve shirt in wintertime. Nick Innova AirTech Instruments has an excellent comfort web site: http://www.impind.de.unifi.it/Impind/didattica/materiale/microclima/i…
Response:
– Hide quoted text — Show quoted text -> The ASHRAE 55-2004 comfort standard (based on worldwide surveys of 21,000 > people) defines the winter and summer comfort zones below with equal air > and wall temperatures, equal human activity levels, and a fixed 0.1 m/s air > velocity: > T (F) RH clo PMV PPD > 67.3 86 1 -.4778556 9.769089 > 75.0 66 1 .4732535 9.676994 > 78.3 15 1 .5239881 10.74283 > 70.2 20 1 -.4779105 9.770202 > 74.5 67 .5 -.4747404 9.706658 > 80.2 56 .5 .5145492 10.53611 > 82.2 13 .5 .5003051 10.23146 > 76.5 16 .5 -.4883473 9.982468 > The winter zone assumes heavier clothing with more thermal resistance > (clo=1), and the summer zone assumes lighter clothing (clo=0.5). The > zones are defined by a +/- 0.5 score on a "Predicted Mean Vote" comfort > scale that varies from -3 (very cold) to +3 (very warm.) The 4 corners > of each zone are based on high and low temperatures and humidities. > The "Percentage of People Dissatisfied" (PPD) score is based on the > PMV. Even with PMV = 0 ("comfortable"), about 6% of the people are > dissatisfied… > If people are willing to change clothing more than twice a year (early > PA farmers had one set of clothes for work and another for church, and > washed them twice a year, when they also took baths
Most people got married in June because they took their yearly bath in May and were still smelling pretty good by June. However, they were starting to smell, so brides carried a bouquet of flowers to hide the smell. Baths equaled a big tub filled with hot water. The man of the house had the privilege of the nice clean water, then all the other sons and men, then the women and finally the children. Last of all the babies. By then the water was so dirty you could actually loose someone in it. Hence the saying, "Don’t throw the baby out with the bath water". Houses had thatched roofs. Thick straw piled high, with no wood underneath. It was the only place for animals to get warm, so all the pets… dogs, cats, and other small animals, mice, rats, bugs lived in the roof. When it rained it became slippery and sometimes the animals would slip and fall off the roof. Hence the saying, "It’s raining cats and dogs," There was nothing to stop things from falling into the house. This posed a real problem in the bedroom where bugs and other droppings could really mess up your nice clean bed. So, they found if they made beds with big posts and hung a sheet over the top, it addressed that problem. Hence those beautiful big 4 poster beds with canopies. The floor was dirt. Only the wealthy had something other than dirt, hence, the saying "dirt poor". The wealthy had slate floors which would get slippery in the winter when wet. So they spread thresh on the floor to help keep their footing. As the winter wore on they kept adding more thresh until when you opened the door it would all start slipping outside. A piece of wood was placed at the entryway, hence a "thresh hold". They cooked in the kitchen in a big kettle that always hung over the fire. Every day they lit the fire and added things to the pot. They mostly ate vegetables and didn’t get much meat. They would eat the stew for dinner leaving leftovers in the pot to get cold overnight and then start over the next day. Sometimes the stew had food in it that had been in there for a month. Hence the rhyme: peas porridge hot, peas porridge cold, peas porridge in the pot nine days old." Sometimes they could obtain pork and would feel really special when that happened. When company came over, they would bring out some bacon and hang it to show it off. It was a sign of wealth and that a man "could really bring home the bacon." They would cut off a little to share with guests and would all sit around and "chew the fat." Those with money had plates made of pewter. Food with a high acid content caused some of the lead to leach onto the food. This happened most often with tomatoes, so they stopped eating tomatoes… for 400 years. Most people didn’t have pewter plates, but had trenchers – a piece of wood with the middle scooped out like a bowl. Trencher were never washed and a lot of times worms got into the wood. After eating off wormy trenchers, they would get "trench mouth." Bread was divided according to status. Workers got the burnt bottom of the loaf, the family got the middle, and guests got the top, or the "upper crust". Lead cups were used to drink ale or whiskey. The combination would sometimes knock them out for a couple of days. Someone walking along the road would take them for dead and prepare them for burial. They were laid out on the kitchen table for a couple of days and the family would gather around and eat and drink and wait and see if they would wake up. Hence the custom of holding a "wake". Church yards started running out of places to bury people. So, they would dig up coffins and would take their bones to a house and re-use the grave. In reopening these coffins, one out of 25 coffins were found to have scratch marks on the inside and they realized they had been burying people alive. So they thought they would tie a string on their wrist and lead it through the coffin and up through the ground and tie it to a bell. Someone would have to sit out in the graveyard all night to listen for the bell. Hence on the "graveyard shift" they would know that someone was "saved by the bell" or he was a "dead ringer".
Response:
>>… PA farmers had one set of clothes for work and another for church, and >washed them twice a year, when they also took baths
They probably used soap and water and washcloths more often… >Most people got married in June because they took their yearly bath in May >and were still smelling pretty good by June… >The floor was dirt. Only the wealthy had something other than dirt, hence, >the saying "dirt poor". The wealthy had slate floors which would get >slippery in the winter when wet. So they spread thresh on the floor to help >keep their footing. As the winter wore on they kept adding more thresh until >when you opened the door it would all start slipping outside. A piece of >wood was placed at the entryway, hence a "thresh hold".
Wordorigins.org: Etymologies & Word Origins: Dirt Poor This term is US in origin and dates to 1937. The exact reference is uncertain, but it is most likely to be evocative of the dust bowl and the extreme poverty and unclean conditions in which many had to live during the Depression. The bit of internet lore about Life in the 1500s claims that it dates to Shakespearian England where finished floors were rare. This is utterly false. >Church yards started running out of places to bury people. So, they would >dig up coffins and would take their bones to a house and re-use the grave. >In reopening these coffins, one out of 25 coffins were found to have scratch >marks on the inside and they realized they had been burying people alive. So >they thought they would tie a string on their wrist and lead it through the >coffin and up through the ground and tie it to a bell. Someone would have to >sit out in the graveyard all night to listen for the bell. Hence on the >"graveyard shift" they would know that someone was "saved by the bell" or he >was a "dead ringer".
The Mavens’ Word of the Day May 15, 2001
I’m interested in the etymology of the phrase dead ringer. I heard that its origins are tied to being buried alive and the idea of a doppelg
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