I am a firm believer in the use of PPE and when I started researching the use of hardeners in paint I was very surprised at the hazards involved. I was even more surprised by the amount of people that only use a half mask with particulate filters. After reading several horror stories from people that ruined there health by inhaling harmful vapors I knew what I needed to purchase. I was able to use my HobbyAir system for the first time today. It gave me a great deal of peace of mind as I was painting with a hardener added to my paint. Absolutely no vapors what so ever. I am using it with the hood. I also am using the disposable hood lens protectors. If i only use it this one time I know it will have been money well spent.