OK That's a BLOG that is built to look like a government agency website. "National Terror Alert" .com is NOT a government website. Crap but I can't remember how to look up the website owner information - anyone remember? I thought it was something like "whois" or something similar?
Sure, you're talking about your life here so it is worth investigating. However everything on that page is alarmist and dismissive. They don't even provide test criteria. It is an obvious advertisement baiting site for Armchair Admirals, nothing more.
The interesting bit I picked up from the filter descriptions are that the filter components decay (corrode?) over time and can lead to chromium toxicity. Never heard that but I suppose it depends on the filter element. I can see needing to replace filters every so often. Makes sense - I have to do it for my fridge
Some were listed simply because they can't use current NATO filters. I know for a fact you buy current NATO filter adapters and simply screw them on so you can use NATO filters (duh) so that seems completely moot. Others though are discarded because they don't meet some high standard of "100% NBC" protection. Well I don't live downwind of a chemical or biological weapons factory so I don't need to worry about tear gas, mustard gas, etc. however I do want protection from chemical spills.
I'm looking at the Finnish masks because while I never plan to fight my way out of a tear gas-infested shootout (c'mon REALLY?!?!?!?!?) I do live in an area just a few miles from a government facility and railroad tracks. Obvoiusly chemical spills or other types of accidents would be my primary concern so I can make tracks upwind! Those seem to be the best deal for what they offer.
HOW TO TEST THEM?
What's a good test? Does anyone actually TEST their masks? Hover over some open chemicals (bleach, ammonia, camp fire, etc) and see if you can smell anything? Other tests to validate? This is something you don't want to find out AFTER you need it!!!