Bill - Thank you for the data sheet. Based on the specs, this material is applicable for extremely light WPB rain wear as would be required for backpacking but, not bushwhacking. It is very similar to the Golite Trinity fabric. It is about half the weight and cost of the most common eVENT fabric. Its waterproofness level is adequate for backpacking applications. Its breathability will necessitate venting options such as pit zips. The DWR will wear off after about 60 miles if you bushwhack through heavy brush.
The hydrostatic head number tells us how water proof the fabric is. 10,000 mm = 1,000 cm = 14.2 PSI. 11.4 PSI is all that is required to sit in water without forcing moisture through. Kneeling in water is a tougher requirement in that a 165 lb man would exert 16.0 PSI. It has the same waterproofness as the Golite Trinity fabric, which is used for similar applications. In contrast, eVENT’s (Nylon Fabric @ 3.1 oz/yd2, 105 g/m2) hydrostatic head is 42.6 PSI but, is 1.9x heavier.
The breathability, (MVTR) using the JIS L1099 test, tells us how well internal moisture vapor will be passed through the fabric. Their spec of 7,000 puts this material in the mid range of breathability. Other options with similar breathability are as follows: Epic nylon = 6,852; Helly-Tech Extreme = 6,696; and Triple Point Ceramic = 5,306. In contrast, 3.1 oz nylon eVENT = 27,826.
The DWR value of 80/20 tells us how frequently we will need to reapply an aftermarket DWR. The durable water-repellent finish increases the surface tension on the face fabric of your garment allowing water droplets bead up and roll off. While not able to withstand much water pressure it will help keep the shell fabric from saturating and reduce the internal condensation, thus keeping you drier and warmer. The test for water repellency is called the Spray Test. Results are given by the % of the fabric still beading up after spraying water on the fabric after washing. For example: 80/20, this means; 80 points (or %) after 20 washing. The higher the points and the more washings the better the DWR is. 80/20 is about the norm for factory applied fluorine based resins. My experience with this type of DWR is that after bush whacking in heavy wet brush for about 60 miles, it needs to be replenished. By contrast, factory applied nanotechnology based DWRs will typically have a rating of 80/100 and EPIC will last the life of the fabric.