Title: +038=627.001-##001T_03-Fasadevasksystem NorAcon - International Code of Practice (ICOP).pdf
O.3.6.1.3.3 Some mid layers incorporate a draw cord through the bottom hem and adjustment at the sleeve cuffs. These can be tightened for optimum heat retention or loosened to provide ventilation. A neck design with a short zip is useful for adjusting ventilation when required.O.3.6.1.4 Outer layerO.3.6.1.4.1 The top (outer) layer should be windproof and water repellent but sufficiently breathable to allow unwanted moisture to escape.O.3.6.1.4.2 Breathability is the ability of a material to allow moisture vapour (e.g. sweat that has been wicked through the base and mid layers) to pass through the fabric. Non-breathable fabric is best avoided because the water vapour wicked through the layers becomes trapped on the inside of the outer layer. The inside surface of the outer layer and the mid layer become wet and the insulating benefits of the layering system are consequently compromised.