Yes.
One of the most famous observatories in the environmental field is Mauna Loa in Hawaii. There are two Brewers at Mauna Loa that are really Environment Canada Brewers. There's a sticker on them that says NOAA, but they are Environment Canada Brewers.
Their function, in addition to gathering data and looking at the ozone in that part of the world, is to help with this calibration method. To calibrate properly you need stable values, and Mauna Loa is a location that gives a fairly stable value, being high up and away from the lowest layer of the atmosphere. It's also away from the polar latitudes, where a lot of interaction takes place to generate ozone.