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Priority: Medium to High
Scale: Processing volume should exceed limitations of small tabletop units currently in use
Points of Contact: Jim Crandall and Melissa James, and Kevin Bush
Specifications
[Describe what the sterilization approach must do to be successful]
- Treating materials with hydrogen peroxide in either the vapor-phase or aerosolized forms can successfully decontaminate exposed, non-soiled surfaces. Decontamination works by neutralizing or removing harmful microorganisms. True sterilization is only achieved via methods that kill 100% of all microbial life, such as steam autoclaves, which are not appropriate for all materials.
- According to 3M, the disinfection method of N95s must:
• be effective against the target organism, such as the virus that causes COVID-19;
• not damage the respirator’s filtration;
• not affect the respirator’s fit; and
• be safe for the person wearing the respirator (e.g. no off-gassing of chemicals into the breathing zone).
Background Information
- [Relevant background on sterilization functionality]
- Price and Chu, Addressing COVID-19 Face Mask Shortages. Stanford Medicine.3/25/20 and updates
- https://radio.wosu.org/post/coronavirus-ohio-battelle-pioneers-technology-clean-and-reuse-ppe#stream/0
CAD Files and Build Instructions
- [Links to CAD files, build instructions, etc.]
Equipment
[What equipment can be used to accomplish sterilization]
- Animal Biosafety Level 3 (ABSL-3) room
- Equipped with bubble-tight dampers with automatic actuators on supply and exhaust ductwork
- Room doors sealed with preservation tape and/or other materials prior to decon cycle to prevent H2O2 leakage
- Cycle parameters verified and routinely validated by Pell Lab staff
- Pell Decontamination (Decon) Chamber
- Stainless steel chamber with two gasket-sealed, locked doors
- Accessible from outside of containment (Pell Loading Dock/Receiving Bay)
- Cycle parameters verified and routinely validated by Pell Lab staff
- Pathogo Curis Decontamination System
- https://www.curissystem.com/
- Touch free, whole room decontamination utilizing Aerosolized Hydrogen Peroxide to achieve a Log 6 reduction which is a 99.9999% kill. Use on all surfaces, beds, computers, office space, high touch areas, equipment and even N95 masks! The easiest to use fogger on the market weighing 36 lbs, is on wheels, and can decon up to 10,000cu ft with one unit. No residue left behind
- Mobile unit, approximately the size of carry on luggage with wheels and collapsible handle
- Unit is physically located inside the room during the cycle. Can be started/stopped remotely with app (iOS only).
- Utilizes 7% Hydrogen Peroxide (H2O2) in aerosolized form
- No certification required for operation; training can be provided
- Currently 4 Pell personnel trained to operate
- Typical cycle time (for full ABSL-3 room decon), including preparation and aeration: 2-4 hours
- No calibration required
- Steris 1000ED Vaporized Hydrogen Peroxide (VHP) Generator
- https://www.sterislifesciences.com/products/equipment/vhp-sterilization-and-biodecontamination/vhp-1000ed-mobile-biodecontamination-system
- Located at Pell Lab with connections specific to the Pell Decon Chamber and each room within ABSL-3 containment
- Located and operated from outside the room/chamber
- Utilizes 35% Hydrogen Peroxide (H2O2) in vaporized form
- Requires certification to operate (online course; renew every 2 years)
- Currently 5 Pell personnel trained and certified to operate.
- Typical cycle time (for full room decon), including preparation and aeration: 24 hours
- Typical cycle time (for Pell Decon Chamber): 6-12 hours (Note: aeration time varies depending on the absorption factor of materials to be decontaminated)
- Calibrated annually
- PortaSens Hydrogen Peroxide Detectors (x2)
- Placed outside of the sealed environment to detect leakage of H2O2 and warn users if ppm meet or exceed OSHA exposure limits
- H2O2 sensors manufacturer calibrated annually
- Biological indicators
- Steris Spordex Biological Indicators
- 10^6 Geobacillus stearothermophilus
- 7-10 day results
- Transfer to growth culture media required
- 18 month shelf life
- Mesa Labs EZTest Self Contained Biological Indicators
- 10^6 Geobacillus stearothermophilus
- 24 hour results
- No transfer to media required, reducing false positives due to post-cycle contamination
- 24 month shelf life
- CrossTex SporView Self Contained Biological Indicators (SCBIs)
- 10^6 Geobacillus stearothermophilus
- Built in chemical indicator on each vial (eliminating need for separate chemical indicators)
- 24 hour results
- No transfer to media required, reducing false positives due to post-cycle contamination
- 18 month shelf life
- Steris Spordex Biological Indicators
- Powered-Air Purifying Respirators (PAPRs)
- Dual HEPA/organic vapor filter cartridges
- Required to enter the room prior to completion of aeration cycle or in the event there is leakage into adjacent space
Relevant Articles
- NEJM letter, Effective sterilization of N95 respirators for reuse, final
- 20160817 Battelle final report FDA N95 Decon_KH_508_sm
- https://radio.wosu.org/post/coronavirus-ohio-battelle-pioneers-technology-clean-and-reuse-ppe#stream/0
- Duke Starts Novel Decontamination of N95 Masks to Help Relieve Shortages
- https://www.safety.duke.edu/sites/default/files/N-95_VHP-Decon-Re-Use.pdf
- https://www.cdc.gov/infectioncontrol/guidelines/disinfection/sterilization/hydrogen-peroxide-gas.html
- Geisinger
- https://absa.org/wp-content/uploads/2020/03/ABJ-200326_N-95_VHP_Decon_Re-Use.pdf
- Boston hospitals getting ‘game changer’ machine that sterilizes 80,000 protective masks a day