California and Colorado, including many public venues and attractions, have banned face masks with valves, as reported by Forbes unless you can just put tape firmly over the valve!
N 95 Masks with valves are for industrial purposes not for medical use.
Don’t just see ‘N-95’ and buy the mask. N95 face masks with one-way valves are readily available to purchase. The valve filter allows your breath to be expelled. Yes, it is cooler and more comfortable in the summer months but not at all helpful. Yes, less restrictive than masks without a valve, but they are also useless in preventing the COVID-19 spread. The Centers for Disease Control (CDC) recommends covering your nose and mouth in order to protect yourself from infection but also to protect others from coming into contact with your respiratory droplets. These masks can put other folks in danger of catching the virus you exhale. Recall even if you have no symptoms you can expel virus. Studies say anywhere from 4-5 days of the virus living in your body to 14 days on average.
The eyes are the other site of virus entry, hence glasses or visors are part of healthcare personnel attire (PPE).