... in well-ventilated areas, where there is no lack of oxygen (> 20%) and where there is no explosive atmosphere. Themask must ... only be used once (no maintenance).Performances :This mask complies with the European directive 89/686, notably regarding ergonomics, innocuousness, comfort, ... Exposure) for verytoxic dust: lead, quartz, chromates). Non woven face mask with valve FFP3EN 104018