This is a FFP3 (or N99) respirator. Only masks designed to filter pathogens from the air are effective against an airborne aerosolised virus like Covid. A simple sign that a mask is a genuine FFP3 is that it has head straps not ear loops - the mask needs to fit tightly. N95 / FFP2 masks are also highly effective (just not quite as protective as FFP3 but more easily available in colours and some people feel they don’t stand out quite as much).

A study early in the pandemic looked for correlations in mask mandates and infection rates and concluded that masking was not an effective public health strategy, noting that too many people didn’t wear masks consistently or properly (remember all the under the nose masks), also at the time everyone was wearing cloth or blue surgical masks, neither of which are designed to filter pathogens.

People minimising Covid risk still reference this study as proving that ‘masks don’t work’. Whether a mask filters a pathogen is a matter of fact, you test it in a lab not by looking to see whether people not wearing the wrong type of mask didn’t seem to stop a virus spreading.

Wearing a proper respirator is the most effective thing you can do at an individual level to reduce risk.