The Food and Drug Administration (FDA) has published an enforcement policy for bioburden reduction systems using dry heat to support single-user reuse of certain filtering facepiece respirators during the outbreak of COVID-19 and public health emergency associated thereto. 


Due to the importance of the issues addressed therein, the present guidance is subject to immediate implementation without prior public consultations prescribed by the general procedures. However, the industry representatives and other interested parties are still allowed to submit their comments and suggestions to be considered by the Agency. 

It is also important to mention that due to its legal nature, the guidance does not implement any mandatory rules and requirements the industry representatives shall follow, but rather provides the current thinking of the regulating authority regarding the matter, while an alternative approach still could be applied, providing that it would be compliant with the applicable regulations. 

The provisions implemented by the policy, and the special temporary and extraordinary measures would remain effective only during the period of the COVID-19 pandemic and public health emergency associated thereto. 

Regulatory Background 

The present guidance describes the enforcement policy for bioburden reduction systems based on the use of dry heat for supporting the single-user reuse of particulate filtering facepiece respirators (FFRs). 

The scope of the guidance covers FFRs that:

  • Do not have exhalation valves,
  • Do not incorporate a duck-bill design,
  • Do not contain antimicrobial/antiviral agents. 

In particular, the scope of the FDA enforcement policy covers the filtering facepiece respirators placed on the market under the emergency use authorization (EUA) – a special framework intended to improve the availability of medical devices and other healthcare products vitally important in the context of the public health emergency – or authorized under the EUA for non-NIOSH-approved FFRS. The scope also covers the FFRs cleared by the Agency for use by healthcare professionals. 

Bioburden reduction systems are intended to address the potential shortages and ensure the availability of the particulate filtering facepiece respirators used for medical purposes in the context of the pandemic.

For the purpose of the present guidance, “bioburden” stands for the population of viable microorganisms on a product and/or a sterile barrier system. 

According to the guidance, the Agency acknowledges that the actual demand for filtering facepiece respirators and personal protective equipment could exceed the current supply level. Under the general rule, healthcare institutions should use entirely new respirators. However, the FDA finds it suitable to use decontaminated or bioburden-reduced respirators, providing that such use is the only available option to deal with the supply shortages. In order to facilitate this approach, the FDA has already issued the appropriate Emergency Use Authorization for certain decontamination systems for decontaminating compatible filtering facepiece respirators. Moreover, there is a tier-based system of categories of decontaminating procedures. In particular, the aforementioned system provides several tiers based on resistance levels. The FDA states that decontamination or bioburden reduction systems could be based on the use of various approaches, while the present enforcement policy covers only the bioburden reduction systems using dry heat.

The FDA additionally emphasizes that NIOSH-approved filtering facepiece respirators that have passed bioburden reduction procedures would not be deemed NIOSH-approved. In order to regain approval, the responsible party shall demonstrate that such a respirator meets NIOSH approval criteria. Thus, the decontaminated NIOSH-approved respirators are not deemed compliant by default, and additional approval is required.

Dry Heat Bioburden Reduction Systems 

The scope of the present enforcement policy covers the bioburden reduction systems using dry heat. Under the general rule, such systems could be used for Tier 3 bioburden reduction of single-user reuse of filtering facepiece respirators. At the same time, in case if the manufacturer of such systems intends to make the appropriate claims regarding their applicability for decontamination for Tier 1 or Tier 2, the provisions of the applicable FDA guidance “Recommendations for Sponsors Requesting EUAs for Decontamination and Bioburden Reduction Systems for Surgical Masks and Respirators During the Coronavirus Disease 2019 (COVID-19) Public Health Emergency” should be applied. The Agency also mentions that till the date of the guidance (November 2020), any bioburden reduction system was not authorized under the aforementioned EUA. 


In order to withstand the impact of potential shortages in the supply of personal protective equipment during the COVID-19 outbreak, the FDA finds it suitable to reuse the single-use disposable filtering facepiece respirator for a limited number of times, providing that such FFRs have passed the appropriate decontamination or bioburden reduction procedure. It is also important to mention that according to the applicable recommendations, the filtering facepiece respirators should not be reused more than five times. 


According to the present enforcement policy, the regulating authority is not going to object to the use of dry heat bioburden reduction systems without additional marketing authorization, providing that such systems are compliant with the applicable recommendations. The Agency also places an emphasis on the importance of the critical cycle parameters and labeling requirements outlined in the present enforcement policy for bioburden reduction systems.

FDA Recommendations for Dry Heat Systems for Bioburden Reduction

With regard to the critical cycle parameters for dry heat systems intended to reduce the bioburden of certain filtering facepiece respirators, the FDA provides the following list of recommendations:

  • In the course of the bioburden reduction procedure, the respirator should be exposed to a consistent temperature of 70C for 60 minutes or 75C for 30 minutes in order to ensure the bioburden reduction. 
  • The temperature and heat distribution should be monitored and recorded.
  • The system should ensure accurate heat distribution.
  • The system should not constitute a household appliance, since it creates significant risks of cross-contamination.  

The enforcement policy also outlines certain recommendations related to the labeling of bioburden reduction systems, namely:

  • According to the information available, the dry heat systems could provide ≥ a 3-log reduction. This information should be properly reflected in the labeling, together with the appropriate restrictions and limitations of use. 
  • The bioburden reduction systems should be applied only for compatible filtering facepiece respirators to ensure sufficient bioburden reduction and continuous effectiveness of the respirator subject to the procedure. 

The healthcare institutions should be also provided with necessary handling instructions describing the way how systems should be used, especially in the part of the prevention of cross-contamination. 

Moreover, the Agency also outlines certain recommendations regarding the labeling of bioburden-reduced filleting facepiece respirators. These recommendations are mostly related to safety warnings, such as:

  • By default, the entirely new respirators should be used, while the limited use of bioburden-reduced respirators is allowed in case if it is reasonably necessary to address potential shortages in supply. 
  • The bioburden-reduced respirator could be reused only by the same person.
  • The respirators subject to bioburden reduction should not be deemed as NIOSH-approved.
  • There are certain limitations regarding the suitability of respirators for bioburden reduction (e.g. the ones used during aerosol-generating procedures or in close contact with the co-infected patients, as well as damaged or contaminated). 

Summarizing the information provided here above, the FDA enforcement policy for dry heat systems intended for bioburden reduction for certain filtering facepiece respirators outlines the ways such systems should be used, the recommendations they should meet, and also existing limitations of use and risks associated thereto.

How Can RegDesk Help?

RegDesk is a next-generation web-based software for medical device and IVD companies. Our cutting-edge platform uses machine learning to provide regulatory intelligence, application preparation, submission, and approvals management globally. Our clients also have access to our network of over 4000 compliance experts worldwide to obtain verification on critical questions. Applications that normally take 6 months to prepare can now be prepared within 6 days using RegDesk Dash(TM). Global expansion has never been this simple.