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WATERPROOF AND BREATHABILITY NUMBERS
WHAT DO THEY REALLY MEAN
FOR WORKERS?
MM WATERPROOF
150D 190T
DX461
3,000-10,000 MM 10,000-20,000 MM 20,000 MM +
The minimum rating for a garment Will withstand moderate to heavy Suitable for those working outdoors
to be called waterproof, suitable for rain but may soak through if in extreme weather conditions, wind
working in light to moderate rain. subjected to pressure such as and heavy rain.
kneeling in very wet conditions.
Waterproof ratings are measured in millimeters (mm), ranging from 800mm to 20,000mm.
For example 10,000mm indicates that a fabric can withstand the pressure of a 10 meter tall Waterproof Level
column of water pushing on it before it starts to let any water through.
MVP BREATHABILITY
3,000-10,000 MVP 10,000-20,000 MVP 20,000 MVP +
Suitable for light physical activity Suitable for heavy physical Suitable for heavy physical
which causes minimal perspiration. activity which results in significant activity which results in significant
perspiration, will require rainwear perspiration.
this breathable.
MVP is Moisture Vapor Permeability and is expressed as g/m²/24 hours, it is the number
of grams (g) of water vapor that can pass through a square meter (m²) of fabric from the Breathability Level
inside to the outside in 24 hours.
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