3M™ Bayonet to MSA® Bayonet Filter Adapter

thingiverse

3M™ Bayonet to MSA® Bayonet Filter Adapter ==================================== A prototype design for 3M™ bayonet to MSA® bayonet adapter. Designed to help cross compatibility of COTS filters with other manufacturer’s respirators to help mitigate this PPE shortage. Disclaimers/Risks: =============== 1.) Use Proper Gaskets Requires gasket/o-ring, below bayonet to ensure proper seal between cartridge and bayonet. Source some gasket or O-ring that is nominal ID 25.5 mm or ~1.0 in. 2.) Perform Proper Negative Pressure Test Follow SSPs established by your institution or workplace for further guidance. But in general, don your respirator, adjust straps till taught against face, ensuring no obstructions around the periphery of the seal against face either due from hair, facial hair, or otherwise. Exhale deeply. Cover all inhalation ports. (Typically, most full face or half face respirators have two filters, so cover those intake ports with your hands. If your running only one filter, ensure the opposite port has filter cap in place.) Now inhale deeply. The mask should suck tightly against your face without any air leakages. Re-test if adjustments are required at gasket/o-ring interfaces at the adapter. 3.) Use At Own Risk – Temporarily Solution Only Until Supply Chain Normalizes 3D printing materials are not resistant to many solvents, are water soluble, and degrade when exposed to chemicals, heat, and UV/sunlight. 3D printing this adapter is only a temporarily ad-hoc solution against biological contagions. In addition to using a properly calibrated 3D printer, due to tolerances of adapters, if possible perform hot nozzle pass on all exterior surfaces, to reduce surface porosity. Highly recommended users apply a thin layer of polyurethane clear coat on all exterior surfaces, spray or dip based methods, to help resiliency and durability for repeated sterilization and to reduce fomite transmission in printed infill layers. Once supply chains return to normal, users should purchase OEM OSHA/NIOSH/EN standard approved respirators, adapters and accessories for their institution and workplaces. Dev. Notes: ========== 04/10/2020 - Initial model release. In work, pending support and feedback from 3D printing community for prototyping and feedback for revisions. Reworked the indexing tab on MSA® bayonet clock position so that when the adapter is tighten down on a 3M™ respirator it should clock properly, but please let me know any revision to the angle position is required. 04/13/2020 - Revised model based on feedback from 3D printing community. The following changes have been made: (1) chamfers added to 3M bayonet to filter mating surfaces to reduce sharp edges that could result in wear on 3M bayonet, (2) redone chamber from underside OD to wrench flats to reduce printing overhang supports, and (3) added engraved markings on exterior periphery to ID adapter. 04/28/2020 - Gen 3 model features the following changes: (1) completely reworked 3M bayonet to filter geometry to ensure proper fitment/compression against OEM gasket in locked position, (2) reduced OAL of adapter and (3) chamfered 45 degrees to the wrenching ears.to remove printing overhangs.