In a contaminated environment with health threatening aerosol a helmet with transparent face shield as an alternative to mask can be used. The helmet protects the entire head of a person using a transparent shield that is knotted at the back of the neck. The helmet uses a fan to suck the environment air, filter it with an aerosol filter and releases the clean air into the interior of the helmet. The contaminated air inside the helmet is filtered and then the clean air is sucked by another fan and released to the environment. The fans are battery powered and their speed can be controlled using sensors and a controller.