Sets of CLIMAT coupons were placed on a pedestal besides the weather station at Canadian Forces Base (CFB) Greenwood, near Kingston Nova Scotia, Canada, and sampled on a monthly basis for five years.
Measured monthly mass loss for a five year period and monthly TOW hours/100 for CFB Greenwood
It is obvious from these results that Winter months (1 is January and 12 December) are the most corrosive months in this particular marine environment. However, the time of wetness (TOW) estimated with the ISO 9223 definition , i.e. number of hours when RH is greater than 80%, is much higher in the Summer months. In fact, the ISO 9223 TOW does not seem to explain the corrosivity of this particular environment.
The corrosivity results measured on the Canadian West Coast during the five year period are shown here. An interesting observation is that the corrosivity of these very distant marine environments seems to follow the same pattern, i.e. corrosive Winters vs. much less corrosive Summers.