According to EU Regulation 2016/425, by Personal Protective Equipment (PPE) we mean any device or item intended to be worn or held by a person for protection against one or more risks to that person's health or safety, as well as any functional complement forming part of that item, even if removable. The personal protective equipment (PPE) is divided into three categories:
Cat I: PPE of simple design intended to safeguard the person against risks of minor physical harm, the effects of which can be identified in good time and without harm to the user.
Cat. II: PPE that does not belong to the other two categories.
Cat. III: PPE of complex design intended to safeguard against risks of death or severe and irreversible injuries.
Standard EN 379 specifies requirements for automatic welding filters that switch their light transmission factor to a lower preset value when a welding arc is triggered (called switchable grade number welding filters).