There are few ways to clean the security insect screen.
Use wet newspapers.
Wet the waste newspapers and attache it to the dirty side of the security insect screen, take it out after few minutes. After few times, the security window screen will become clean as new one.
Spray water onto it by a watering can, then dry it by a towel.
Clean the security screen for windows or doors by a vacuum cleaner.
Use a brush to clean the security screen. Easy to operate.
Use a wet sponge to clean the safety insect screen for windows and doors.