3M™ Bayonet to MSA® Bayonet Filter Adapter

thingiverse

A Design for Cross-Compatibility of COTS Filters with Various Respirators This design aims to bridge the gap between disparate respirator models by creating an adapter that allows for seamless integration of common off-the-shelf (COTS) filters. By doing so, it helps alleviate the Personal Protective Equipment (PPE) shortage. Important Safety Precautions: 1.) Ensure Proper Gasket Sealing To guarantee a secure seal between the cartridge and bayonet, use a gasket or O-ring with an ID of 25.5 mm or approximately 1.0 in. Obtain one that fits this specification. 2.) Conduct Negative Pressure Tests Follow your institution's Standard Operating Procedures (SSPs) for further guidance, but generally, put on your respirator, adjust the straps until they're snug against your face, ensuring no obstructions around the seal area. Exhale deeply, then cover all inhalation ports with your hands or by using filter caps if necessary. Now inhale deeply; the mask should conform tightly to your face without any air leaks. Re-test if adjustments are needed at gasket interfaces. 3.) Use at Your Own Risk – Temporary Solution Only 3D printing materials have limitations, including susceptibility to solvents, water solubility, and degradation from heat, chemicals, and UV/sunlight. This adapter is a temporary solution until the supply chain normalizes. To enhance durability, apply a thin layer of polyurethane clear coat on exterior surfaces using spray or dip methods. Development Notes: 04/10/2020 - Initial model release; pending community feedback for revisions and support. 04/13/2020 - Revised model incorporating changes from 3D printing community feedback: (1) chamfers added to 3M bayonet to filter mating surfaces, (2) reworked chamber to reduce printing overhang supports, and (3) engraved markings on the exterior periphery for identification. 04/28/2020 - Gen 3 model features: (1) completely reworked 3M bayonet to filter geometry, ensuring proper fitment/compression against OEM gasket in locked position, (2) reduced overall length of adapter, and (3) chamfered 45 degrees on wrenching ears.