The 3M™ 4251+ maintenance-free half mask has filter type FFA1P2 R D. It protects against organic vapours (good warning properties, boiling point above 65 °C) up to 10x the workplace exposure limit (WEL) or 1000 ppm, whichever is lower, and against particulates up to 10x WEL.
The 3M Maintenance-Free Half Mask 4000+ Series is a range of simple, ready-to-use respirators with integrated cartridges and filters, available in four models.
A newly enhanced valve assembly helps reduce exhalation breathing resistance for improved breathing comfort*. The textured face seal is soft, non-allergenic and silicone free. The lightweight, well-balanced design has a centrally positioned exhalation valve that helps reduce heat and moisture build-up, keeping you comfortable in hot and humid conditions.
The integrated cartridges and filters are maintenance free: use the mask until your change-out schedule indicates a replacement is needed or the filters are full, then discard it. An adjustable head cradle fits a broad range of head shapes and sizes, and the neck straps are easy to fasten. The low-profile design does not hinder peripheral vision, and the two large bonded-carbon filters give low breathing resistance. A resealable bag is included for hygienic storage and transport.
*Exhalation breathing resistance of the 3M 4000+ is reduced by more than 30% at 120 l/min peak exhalation flow and more than 35% at 160 l/min compared with the 3M 4000 Series. Results measured by 3M in 2017 under laboratory conditions. Breathing rates shown as an example only.
