Simms ColdWeather Hoody
Simms ColdWeather Hoody is an all time favorite for fall and spring fly fishers. The ever popular ColdWeather shirt now comes with an attached hood for extra cold weather comfort. Two large fly box compatible chest pockets, off shoulder seaming for both comfort and articulation and drawcords for the hood are some of the features this Coldweather Hoody offers. The Simms cold weather hoody comes with a slight drop tail and a waffle fleece lining. While the shell is made of a polyester flannel, the hood is a slicker, solid colored polyester waffle fleece. Also a great piece to wear off river into town or even working in the yard.
FABRIC TECH: 147gsm 100% polyester flannel shell; 200 gsm 100% polyester waffle-fleece liner; 2-layer 200gsm 100% polyester waffle fleece hood.
FEATURES & BENEFITS:
• Wicking & UPF50
• Two fly box compatible chest pockets with hook-&-loop closure
• Off-shoulder seaming for comfort & articulation
• Slight drop tail
MEN'S SPORTSWEAR TOP SIZE CHART
MEN'S SIZES CHEST* NECK* SLEEVE* S 36" - 38" 14.5" - 15" 33" - 34" M 39" - 41" 15.5" - 16" 34" - 35" L 42" - 45" 16.5" - 17" 35" - 36" XL 46" - 48" 17.5" - 18" 36" - 37" XXL 49" - 51" 18.5" - 19" 37" - 38"
* These are body measurements
About ColdWeather Insulation
Mechanisms of ColdWeather insulated Apparel
There are three kinds of heat transfer: conduction (exchange of heat through contact), convection (movement of air), and radiation.
Air has a low thermal conductivity but is very mobile. There are thus two elements that are important in protecting from the cold:
- stopping the wind from penetrating and replacing the layer of warm air close to the body;
- setting up a layer of still air which serves as insulation, by the use of fibres (wool, fur, et cetera).
Another important factor in ColdWeather insulation is humidity. Water is a good conductor of heat, thus if clothes are damp — because of sweat, rain, or immersion — water replaces some or all of the air between the fibres of the clothing, causing heat loss through conduction and/or evaporation.
Thermal ColdWeather insulation is thus optimal with three layers of clothing:
- a insulated layer near the body for hygiene (changed more often than the other clothing), whose role is to get rid of sweat so it does not remain in contact with the skin;
- an outer close-knit or closely woven layer as a wind breaker, usually thin — if there is a risk of bad weather this should be impermeable, the ideal being a textile that stops water droplets but allows water vapor to pass so as to remove evaporated sweat (a textile of this sort is said to "breathe");
- and between the two, a "thick" layer that traps the air and prevents contact between the skin and the wind-breaking layer (which, as it is thin, gets close to the ambient temperature).
The three layers of air between the skin and the exterior layer also play an insulating role. If the clothing is squeezed tight (as by the straps of a backpack), insulation will be poorer in those places.
Units and Measurement Of ColdWeather Insulation
Clothing coldweather insulation may be expressed in clo units. The clo has the same units as the R value used to describe insulation used in residential and commercial construction. The clo value is also similar in magnitude to the R value.
- 1 clo = 0.155 K·m²/W = 0.88 R
This is the amount of insulation that allows a person at rest to maintain thermal equilibrium in an environment at 21°C (70°F) in a normally ventilated room (0.1 m/s air movement). Above this temperature the person so dressed will sweat, whereas below this temperature the person will feel cold.
There are a number of ways to determine clothing coldweather insulation provided by clothes, but the most accurate according to ASHRAE Fundamentals are measurements on heated manikins and on active subjects. Equations may then be used to calculate the thermal insulation. Because clothing insulation cannot be measured for most routine engineering applications, tables of measured values for various clothing ensembles can be used. According to ASHRAE-55 2010 standard, there are three methods for estimating clothing insulation using the tables provided.
- If the ensemble in question matches reasonably well with one on Table 1, the indicated value of intrinsic clothing insulation can be used;
- It is acceptable to add or subtract garments on Table 2 from the ensembles in Table 1 to estimate the insulation of ensembles that differ in garment composition;
- It is possible to define a complete clothing ensemble as a combination of individual garnments using Table 2.
Another coldweather unit which is used is the "tog":
- 1 tog = 0.1 m²·K/W ≈ 0.645 clo
- 1 clo = 1.55 togs
The word "togs" is a British slang term for clothes.