### 1 Response to Comments Document for the 810.2000 Series Product Performance Guidelines

January (insert date) , 201 2 This document summarizes the comments received in response to the 810.2000 Series Product Performance Guidelines for Sterilants, Disinfectants and Sanitizers , wh ich were proposed on January 27, 2010, and provides the Agency’s response s to those comments. The following groups submitted comments to the docket, # EPA
- OPP
HQ
- 2009
- 0681. They are listed by their assigned docket designation. 0007 Keller and Heckman 0009 Public Employees for Environmental Responsibility 0010 Kimberly
- Clark Corporation 0011 Ecolab 0012 The Clorox Company 0013 Patton Boggs LLP, Metrex Research, LLC 0014 Lonza, Inc. 0015 Consumer Specialty Pro ducts Association **1. General Comments**  **( 5**  **)** 1.1 Comment (0009, 0013): Two commenters expressed concern over the non
- binding nature of the guidelines. Agency Response: The guidelines are non
- binding because they are guidelines and not regulations

. However, the data requirements to which the guidelines relate are codified in the regulations. 1.2 Comment (0009): The draft guidelines do not adequately consider the environmental and human health risks posed by antimicrobial pesticides. Agency Response: These guidelines are intended to make recommendations on methods to be used in tests conducted to address the data requirements for product performance ; these are not intended to address human health and environmental risks that could be pose d by the use of antimicrobial pesticides. The data requirements for human health and environmental risks do and are in 40 CFR Part 161

. 1.3 Comment (0009) : The EPA has failed to adequately consider whether public health
- related antimicrobial pesticides benefit avera ge consumers. Agency Response: The Agency has considered and understands the relationship between the use of antimicrobial pesticides and their benefit to average consumers. Wh ile the average consumer uses antimicrobial products to

### 2 reduce the number of g erms in their household, t he healthcare community also relies on antimicrobial pesticides as an important component of a comprehensive infection control program. Antimicrobial pesticides, along with hand washing, isolation precautions and the use of barrie r materials support the needs of infection preventionists in reducing the number of microorganisms on treated surfaces

. 1.4 Comment (0007, 0011) : Two commenters stated the need for additional guidelines for commercial sterilants for aseptic packaging. One commenter provided language to go into the guidelines regarding the testing of products for aseptic packaging label claims. Further, one of the commenters “requests that EPA’s guidelines for product performances of public health uses of antimicrobial a gents acknowledge that validated testing acceptable to FDA also provides adequate assurance of commercial sterility for use in FDA regulated aseptic food processing operations.” Agency Response: The Agency will add the suggested language regarding test procedures and measures of success for products with label claims for aseptic packaging into a new section , designated as (j) in 810.2100

– Sterilants for Use on Hard Surfaces under the heading “Aseptic Packaging

. ” The Agency is aware and supports the Food and Drug Administration’s program for validating testing processes for commercial sterilants. 21 CFR Parts 108, 110, 113 and 114 deal with the packaging, compliance, good manufacturing practices, validation and other safety and control standards that foo d processors need to follow to ensure “commercial sterility” for aseptic packaging. However, this program does not relieve EPA of its statutory authority to regulate antimicrobial products (like commercial sterilants for aseptic packaging). EPA intends to develop additional guidance directed to aseptic packaging products , and sterilants intended for use in validated systems, in the near future. 1.5 Comment (0015): The sections on “Data collection and reporting” and “Data for recommended methods” should be removed from 810.2100, 810.2200 and 810.2300 and placed in 810.2000 for consistency

. Agency Response: EPA disagrees with removing the sections on “Data collection and reporting” and “Data for recommended methods” from 810.2100, 810.2200 and 810.2300 , and placing the sections in 810.2000

. Since each guideline is intended as a stand alone document , it is important to retain the sections on “Data collection and reporting” and Data for recommended methods” in each individual guideline.
**2. Comments on**  **810.2000 Overview**  **(2 4 comments**  **)** 2.1 Comment ( 0013, 0015):

### 3 Previous guidelines: The Agency should make the 91 B Non
- Public Health Guideline Series available on the EPA website and add citations to the guidelines for non
- public health applications and for the interpretive instructions found in the Preamble of Subdivision G (e.g., Agency philosophy, waiver information, dose and effect iveness evaluations, instructions for adjuvants, geographic distribution of testing, study design, report content, test substance, application and equipment use). The Agency should update all non
- public health guidelines. Agency Response: The Agency will post the non
- public health Guideline Series 91B on the Antimicrobials Division’s website. This posting will include a comparison that identifies the relevant sections in the 810 guidelines that match with the fo rmer 91 A series numbers in Subdivision G. Mo st of the information cited in the Preamble of Subdivision G can be found within 810.2000

. At this time, the Agency has no plans for updating the non
- public health guidelines. 2.2 Comment (0015) : Test organisms should always be cited throughout the docum ent with an identifier (e.g., ATCC number) where one is defined. Agency Response: The Agency agrees and will add identifiers where they are missing. 2.3 Comment (0015) : The commenter requested a description (e.g., title, description of future content) for all sections labeled as “Reserved” and that these sections not be left open without clarification. Agency Response: T he term “Reserved” will be removed from the guidelines.
2.4 Comment (0015): In appropriate places, replace “should” w ith “must” as the term “should” may leave the document open for too much interpretation. Agency Response: At places in this guidance, the Agency uses the word “should

. ” Use of “should” with regard to an action means that the action is recommended rather than mandatory. Since these are guidelines and not regulations, the use of the word “must” instead of “should” is not appropriate.
2.5 Comment (0015) : The title for 81 0.2000 should be changed to “General Considerations for the Uses of Antimicrobial Agents” since it is positioned as an overview document describing how the Agency views all antimicrobial agents. Agency Response: The Agency disagrees with the comment . The majority of information , with the exception of some of the definitions, in 810.2000, “General

### 4 Considerations for the Uses of Antimicrobial Agents ” refers to public health uses of antimicrobial agents. 2.6 Comment (0015): The 810 guideline s are lacking a discussion on the emerging pathogen policy. Agency Response: The emerging pathogen guidance deals with labeling of disinfectant products in emergency situations. The Agency does not believe the product performance guidelines are the appropriate docume nt for discussing the emerging pathogen guidance, which can be found at http://www.epa.gov/oppad001/disinfection_hier.htm
2.7 Comment (0010, 0015): Define the terms “Volatile” and “Non
-volatile

. ” Agency Response: The Agency agrees and will provide definitions for “volatile” and “non
-volatile

. ”
2.8 Comment (0010, 0015): The commenters support the Agency’s goals to periodically update the guidelines and adopt new quantitative methods. All updates must be vetted through a public notice and comment period and new methods must not be adopted without thorough validation. The l evel of stringency for new methods must be aligned with the stringency of historic methods. Adoption of new methods and criteria must not force widespread reformulation of products, which have been available, effective products registered for decades, to h ig her levels of active ingredient resulting in greater human and environmental safety concerns. Agency Response: The Agency agrees that in general new methods should be validated prior to adoption , and public notice and comment should take place before a method is accepted for use. The Agency also believes that as the state
of
-the
- science evolves and new information becomes available regarding disinfection principles, processes and test methods, new methods may not always align in stringency with historic methods. The Agency will uphold its responsibility to consider and adopt methods that are protective of public health. Depending on the test results, the impact to an individual product would have to be assessed on a case
- by
- case basis.
2.9 Comment (001 5): New methods that have been approved through the internal protocol review process must be published on the EPA website until such a time as it can be added to these Guidelines.

### 5 Agency Response: The Agency agrees that new methods approved through the internal protocol review process should be published on the EPA website. Methods that have previously been approved and newly approved methods will be posted to the Antimicrobials Division website. However, in some instances, scientific information has ari sen that may change the Agency’s decision concerning a previously approved protocol. Such protocols will not be posted to the website or they will be removed if already posted.
2.10 Comment (0015): Adoption of AOAC methods should not occur until the met hod has achieved final status. Agency Response: The Agency disagrees with the comment . Methods that have achieved First Action by AOAC have been fully vetted and validated prior to acceptance by AOAC. Since these First Action methods have undergone validation, the Agency believes it is acceptable to adopt them for use. AOAC allows a two year period for meth ods to reach Final Action S tatus

. Methods that do not reach final status may be delayed (dependin g on the nature of the comments) or repealed. In that case the Agency will need to decide whether to retain us e of the method.
2.11 Comment (0015): The assertion that all disinfectants are considered to be human health
- related, whether or not control of infectious microorganisms as specifically claimed , is not correct. Agency Response: The Agency agrees with the comment and has revised the section on public health claims to read: “An antimicrobial pesticide is considered to make a public health claim if the pesticide product bears a claim to control pest microorganisms that pose a threat to human health, and whose presence cannot readily be observed by the user, including but not limited to, microorganisms infectious to man in any area of the environm ent.”
2.12 Comment (0015): Insert a place holder for mold remediation products. Agency Response: As new guidelines are developed, the Agency will incorporate them into the 810 series

. It is not necessary to add a place holder for each potential guideline.
2.13 Comment (0015): Revise the title in Section (c ) ( 2 ) ( B) to include fungistatic products.

### 6 Agency Response: The Agency agrees with the comment and will revise s ection (c)(2)(B) in 810.2000 to include fungistatic products.
2.14 Comment (0015): Revise the sentence in Section (c ) ( 2 ) ( D) by changing the “or” to “and” so that it states , “

. . . the Ag ency is requesting the submission of efficacy data to support these claims because these pathogens have animal health significance and the potential to infect humans

. ” Add a reference to a list of organisms that meet the criteria for which testing is required. Agency Response: The Agency dis agrees with the comment because the Agency would want to review the data in either case (significant anim al health pathogen or the potential to infect humans) and has not made the suggested change to s ection (c)(2)(D) in 810.2000

. 2.15 Comment (0015): Commenter believes all definitions must agree with those definitions provided in FIFRA (e.g., antimicrobial pesticide, disinfectant, etc

. )

. For those terms not defined in FIFRA, definitions consistent with those found in standard methods employed in testing antimicrobials should be used

. Definitions for additional terms used in the Guidelines have been provided

. The statement “For the purposes of these guidelines, slimicide claims are reserved for non
- public health industrial label claims” is inappropriate. Agency Response: The Agency has revised the definition for slimicide to remove the statemen t “are reserved for non
- public health industrial label claims

. ” The Agency has determined this statement is not appropriate for the guidelines because it deals with labeling and not tests that are recommended to support a label claim

. Additional definition s for slime, volatile, non
-volatile and revisions to the definition of a biofilm have also been made. Revisions have also been made to the definitions for sanitizer and disinfectant, however, the descriptors of these terms that are outlined in FIFRA sectio n 4(i)(4)(C), which , by its own wording, concerns only the reduction or waiver of fees for minor uses, were not used to define these terms.
2.16 Comment (0010, 0011, 0012, 0014 and 0015) : Several comments were made regarding testing formulations at the lower certified limit(s) (LCL) of the active ingredient(s). Most of the commenters agreed that formulations should be tested at the lower certified limit(s) of the active ingredient(s). However, for products that contain multiple actives, have inverse rela tionships (e.g., peracetic acid/peroxide), or the active is created in situ , producing batches with all the actives at the lower certified limits may be difficult or impossible to achieve. Suggestions for revised language were provided.

### 7 Agency Response: The Agency agrees there may be situations where it may not be technically feasible to test at the exact LCL (e.g., reactive chemistries with a degradation profile, multiple active ingredients and formulations with inversely related active ingredients) ; a rationale should be provided to the Agency for approval of the testing that cannot be performed at the LCL. Efforts should be made to test as close to the LCL as possible. The suggested language from the commenter has been incorporated into 810.2000, sect ion (e)(1)(v).
2.17 Comment (0015): For the HBV, HCV and Norovirus studies, the fact that the data consistency controls found in the methods posted on the EPA web site are no longer required should be reflected in the 810.2000 guidance. Agency Response : The Agency agrees with the comments and believes the data consistency controls are no longer needed for the HBV, HVC and Norovirus surrogate methods because sufficient data has been generated using these controls and shown that the data for these surrogates is consistent. The Agency will remove the data consistency controls from these methods that use surrogates for HBV, HCV and Norovirus

. 2.18 Comm ent (0010, 0013) : Two comments were made regarding the addition of an organic soil load in efficacy tests. One focused on the addition of organic soil to suspension based tests where the example given in the guidelines provides for the soil be ing added to the test substance. The commenter believes the soil load should be added to the test microorganism. The second commenter requests clarifying language be added, so that if the product requires pre
- cleaning of the surface of gross debris before the use of t he spray disinfectant or towelette, it is clear the EPA’s test method does NOT call for the addition of organic soil such as blood serum. Agency Response: The Agency agrees with the first comment. For suspension based tests, the soil should be added to t he test inoculum to achieve 5% of the test inoculum . The Agency also agrees that products requiring a pre
- cleaning step do not call for the addition of organic soil in the test. Th e lack of the need for an organic soil when a pre
- cleaning step is included on the label is also stated in Section (g)(3)(i) of the 810.2000 guidelines.
2.19 Comment (0015): The Agency routinely accepts shorter time periods than are listed in methods. This section is worded in a way that makes it seem like registrants must seek Agency concurrence before conducting studies with shorter time periods. This is burdensome for both the Industry and the Agency when current policy allows tim e reductions on a routine basis.

### 8 Agency Response: The Agency agrees with the comment. Section (g)(4) will be revised to state that shorter contact times than those listed in standard methods are allowed without obtaining Agency review prior to conducting the studies. Any resulting claims would reflect reduced contact time.
2.20 Comment (0015): The proposed Guideline does not include any reference to use/reuse studies. Wh ile use/reuse is most commonly associated with reprocessing of medical equipment, an FDA regulated claim, there may be instances where use/reuse is indicated for EPA applications. Thus, registrants want to maintain the right to have this use on EPA regulated products. Agency Response: The Agency does not envision situations where reus e of dirty disinfectant products would be appropriate. As stated in the comment, reuse is most commonly associated with reprocessing medical equipment and is therefore an FDA regulated claim. Therefore, references to reuse of disinfectant products will not be included in the guidelines.
2.21 Comment ( 0012, 0015): Considering that n eutralization is a key part of any antimicrobial study, a more detailed description of neutralization techniques and its importance should be highlighted in this document. Age ncy Response: The Agency agrees with the comment and has revised s ection (h)(3) to provide a more detailed description concerning neutralization techniques.
2.22 Comment (0010): The statement “The Agency reserves the option to perform its own tests for validation of efficacy of products selected on a case
- by
- case basis” should be revised to read, “The Agency reserves the option to perform its own tests following the protocol submitted with the registration for validation of efficacy of products selected on a case - by
- case basis.” Agency Response : In general, t he Agency agrees with the comment

. When the protocol submitted for registration meets current recommended protocols, the Agency will use that same protocol when performing its own validation tests. If the protocol does not meet current agency standards, the Agency will use its own protocol to conduct validation studies on a product. The Agency will revise the statement to read, “The Agency reserves the option to perform its own tests, on a case - by
- case basis, following the protocol submitted with the registration , if that protocol meets current agency standards. In all other cases, the Agency will conduct the validation studies using the current agency protocol. ”

### 9

2.23 Comment (0010, 0012 and 0015): Several commenters requested clarifying information be added to the guidelines regarding the repeat testing of low level failures. Agency Response: The Agency does not have a formal policy regarding the repeat testing of low level failures. The industry has historically repeated low level failures (e.g., 2

– 3 positive carriers out of 60 carriers) when the results from an analyst come under question or there is contamination in the system. The Agency believes the regulated industry is familiar with the se limited instances where repeat testing should be conducted and that it is not necessary to include this information in the test guidelines.
2.24 Comment (0015): The commenter recommends adding a section that describes what information should be include d in a final report. Agency Response: The Agency has already included a list of the information that should be included in a final report at the end of each test guideline.

**3. Comments on 810.2100**  **Sterilants (15 Comments)** 3.1 Comment (0010) : The commenter believes it is inappropriate for the Agency to share developing methods with organizations outside of the Agency, and requests the following statement be deleted: “ The Agency may consult with AOAC prior to accepting modifications to their standardized methods. ” Agency Response: The Agency disagrees with the comment

. Methods that have been validated through a standard setting organization should not be changed without consultation with the standard setting organization

. 3.2 Comment ( 0010 , 0015): The commenters requested removal of the carrier count range (1 x 10 5

– 1 x 10 6 ) for spore forming bacteria. If the carrier count range is retained, one commenter requested removal of the word “approximately” from the section on Bacillus anthracis

. Agency Response: The carrier count range needs to be retained so that a minimum spore count of at least 5 to 6 logs on each carrier is assured. The Agency agrees that the word “approximately” wh ere in the proposal it modified the number of spore formin g units per carrier is not needed because a finite

### 10 range is set for the number of spore forming units that should be achieved per carrier. T he word will be deleted from the section on Bacillus anthracis

. 3.3 Comment (0015): The 810.2100 Guideline is mis sing information on the use of porous carriers as the more stringent test standard. In 810.2000, (g)(1 ) Type of Surface, a hard, porous carrier may be substituted for a non
- porous carrier. The statement is as follows: “Since the use of a hard, porous surfa ce would simulate the more stringent test condition, demonstrated efficacy on hard, porous surfaces would suffice to support an analogous claim for efficacy of the product on hard, non
porous surfaces as well.” Agency Response: The Agency agrees with the comment and has added the language dealing with porous carriers from 810.2000 (g)(1) into the guideline under “General considerations

. ”
3.4 Comment ( 0010, 0015): Official Methods of Analysis of AOAC International, Official Method 966.04 Sporicidal Activity of Disinfectants test, Method II is limited to use for Bacillus subtilis ( B. subtilis ) spores dried on porcelain penicylinders. This method has not been validate d for B. subtilis spores dried on suture loops or and Clostridium sporogenes dried on porcelain penicylinders and suture loops. Include Sporicidal Activity of Disinfectants Test, Method I in the recommended tests. Agency Response: The Agency agrees with the comment and will include the Sporicidal Activity of Disinfectants Test, Method I among the recommended tests. However, it will be noted in the guidance document that Method I will no longer be applicable when AOAC issues First Actio n S tatus to the validated Method II for B. subtilis spores dried on suture loops, and for Clostridium sporogenes dried on porcelain penicylinders and suture loops. 3.5 Comment ( 0015): Include an explanation of the term “failures” under the section “Eva luation of Sterilant Success

. ” Agency Response: The Agency agrees and has added an explanation of the term “failures” to the evaluation of success section

. 3.6 Comment (0010, 0015): The commenters are requesting independent validation testing for sterilant label claims be conducted in either a separate facility or in the same facility as the initial testing but with separate staff. This request is being made because there are a limited number of laboratories that have expertise in sporicidal testin g.

### 11 Agency Response: The Agency agrees with the comment . Independent validation testing for sterilant label claims may be conducted in the same facility as the initial testing so long as the study director , staff and QA auditor are not the same individual s who we re involved in any way in the initial testing. 3.7 Comment (0015): The commenter requests the removal of the term “interim guidance” under the section addressing testing against Clostridium difficile ( C. difficile )

. Agency Response: The Agency disagrees and will continue to use the term “interim” guidance until it believes the science issues under development surrounding testing for C. difficile have been adequately resolved

. 3.8 Comment (0010): The commenter requests clarification that the va lidation testing is not required for Clostridium difficile claims. Agency Response: The Agency agrees and has added c larification that validation testing is not part of the recommended testing for C. difficile claims. 3.9 Comment (0010, 0015): The commenters request the Agency clarify how to achieve a 90% spore purity limit. Agency Response: There are several means to obtain a 90% spore purity limit, including using a physical process (e.g., HistoDenz) or chemical enzymatic digestions (e.g., lysozym e, trypsin). 3.10 Comment (0010, 0015): Revise the Test procedure for C. difficile sporicides

– quantitative testing to include the number of carriers to be used in each of the three recommended methods. Agency Response: The Agency agrees and will in clude the number of carriers to be used for each of the three recommended methods. 3.11 Comment (0010): Since no survivors are allowed in the qualitative test for C. difficile , the quantitative tests should be held to the same criteria. Agency Response: The Agency disagrees with this comment . The performance standards for the qualitative test (which is a presence/absence test) are different from those of the quantitative test (which allows for survivors in order to fa cilitate calculat ing a log reduction). 3.12 Comment (0010):

### 12 Include a section which addresses testing towelette products against C. difficile

. Agency Response: The Agency agrees and has added a section which addresses testing the use of towelette products against C. difficile

. 3.13 Comment (0015): The commenter requests the Agency provide a list of surrogate organisms to be used in testing for claims against Bacillus anthracis ( B. anthracis). Agency Response: EPA does not have a list of surrogate bacterial spores for use in testing for claims against Bacillus anthracis ( B. anthracis )

. Because the susceptibility of spores to inactivation varies according to the antimicrobial che mical to w hich they are exposed, the strain of bacterial spore(s) that would be acceptable as surrogates to B. anthracis spores may vary

. Accordingly, it is the responsibility of the registrant to provide data and/or a persuasive rationale as to wh y a particular bacterial spore strain sho uld be an acceptable surrogate. 3.14 Comment (0015): Define the statement “appropriate positive and negative controls should be employed ”. Agency Response: “Appropriate positive and negative controls ” are those controls used in the method to demonstrate a valid test, including but not limited to; neutralization confirmation, sterility, purity, negative or inert substance, etc. 3.15 Comment (0015): The commenter requests a rationale for how the target count of 1 x 10 7 spores per carrier was determined and whether it has been collaborated and validated. Agency Response: The target count of 1 x 10 7 spores per carrier was determined to be necessary to demonstrate a 6log 10 reduction in the quantitative test methods. It has been collaborated and validated in past studies that required a 6 log 10 reduction as a performance criteri on
. **4. Comments on 810.2200**  **Disinfectants ( 12**  **Comments)** 4.1 Comment (0015): The commenter requests an upper limit be assigned to accompany the minimum mean log density for Staphylococcus aureus ( S. aureus ) and Pseudomonas aeruginosa ( P. aeruginosa ). Agency Response: The Agency agrees with the comment and is currently working on establishing an upper limit to accompany the minimum mean log density for Staphylococcus aureus and Pseudomonas aerugin osa. This upper limit will be added to the guidelines once it is established.

### 13

4.2 Comment (0015): Documents, references and methods cited in 810.2200 should be made publically available. For example: Sanitizer for Urinal and Toilet Bowl W ater and In
-tank Sanitizers, EPA Sanitizer Test, 1976 and any unpublished DIS/TSS documents. Agency Response: The Agency agrees with the comment and will post the methods for In
-tank sanitizers and other current Agency methods on the Antimicrobials Division’s website. 4.3 Comment ( 0015): References to specific test methods should be modified to delete the edition nu mber since it needs to be communicated to the user community that standard practice needs to be to use the most recent revision of the method. Agency Response: The Agency agrees and will delete the edition numbers. The guidelines will state that the reference is to the most current edition of the test methods. 4.4 Comment (0015): The information provided allowing for the use of the Hard Surface Carrier Test needs to be further defined in the success criteria to include the carrier count req uirements for each test organism. Agency Response: The Agency agrees and will include the carrier counts for each test organism for the Hard Surface Carrier Test. 4.5 Comment (0015): The mean log density for S. aureus is listed as at least 6.0 (corresp onding to a geometric mean density of 1 x 10 6 ). Is this a requirement even though the corresponding test method is not a Final Action? Agency Response: The Agency recommends a mean log density of at least 6.0 (corresponding to a geometric mean density of 1 x 10 6 ) for Staphylococcus aureus
. The Agency believes that any method that has achieved First Action Status has been fully vetted and validated by the AOAC and is, therefore, acceptable for use by the Agency

. 4.6 Comment (0010) : Revise the sentence “In addition, per the 2009 revisions for the Use
- Dilution Method, the mean log density...” to read “In addition, when testing with the AOAC Use
- Dilution Method per the 2009 revisions, the mean log density... ” This clarification is needed to communicate that th e carrier count density requirements described are only applicable to testing with the AOAC Use
- Dilution and therefore, do not apply to the other AOAC methods discussed in the section.

### 14 Agency Response : The Agency agrees and will make the suggested clarification to the section describing the recommended method

. 4.7 Comment (0015): The Agency needs to define the total volume to be used for calculation of the appropriate use dilution used for testing of toilet bowl products

. The current guidance requires t he use of 96 fl oz as representative of a typical toilet

. With the inclusion of low volume toilets in homes the total volume needs to be adjusted. Agency Response: The Agency agrees and has added language to address the amount of water involved when deal ing with low volume toilet bowls. 4.8 Comment (0015): The inoculum employed for Fungicidal activity currently specifies a concentration of 1 x 10 4

– 1 x 10 5 conidia per carrier. This level has not been validated, collaborated or discussed through an SAP process. How was this level derived? Agency Response: This level was derived through Agency discussions with commercial testing laboratories that provided data that the Agency reviewed and used to determine that 1 x 10 6 conidia per carrier level was difficult to achieve. 4.9 Comment (0015): The minimum carrier count and therefore success criteria for efficacy against additional organisms is not defined. The commenter requests the Agency provide guidance based on discus sions with industry. Agency Response: The minimum carrier count for additional organisms has always been expressed as no lower than 1 x 10 4 in the DIS/TSS guidance document number 1, under the section addressing testing of additional microorganisms. 4 .10 Comment (0015): The Multiple
- Use Towelette language from previous guidance documents for testing towelettes should be added to the guideline. Agency Response: The Agency disagrees with the comment because g iven the many towelette materials and label claims associated with this type of product, the Agency recommends a pre
- registration meeting to discuss this product prior to registration. 4.11 Comment (0013): EPA’s Test Method Does Not Address Towelette Size, but Should Do So. Agency Response: Th e Agency disagrees with the comment because the amount of liquid in the towel ette is more important than the actual size of the towel ette

.

### 15

The towel ette should be capable of dispensing enough liquid to keep the surface wet for the specified contact time li sted on the label. 4.12 Comment (0013): EPA’s Test Method Uses an Unrealistic W iping Procedure Agency Response: The Agency disagrees with the comment. The wiping procedure employed in the test is intended to simulate the back and forth motion of the towelette in actual use. The wiping is conducted on a stable surface similar to what would occur in practice. **5. Comments on 810.2300**  **Sanitizers (7 Comments)** 5.1 Comment (0010) : The commenter states that virucidal testing should be allowed for all forms of sanitizing products

. Virucidal activity is equally critical in food service applications as in healthcare and general disinfection uses

. The FDA National Food Code (2009) states “Viruses such as Norovirus, hepatitis A and rotavirus are directly re lated to contamination from human feces

. In most cases, however, contamination of food by viruses is the result of cross
- contamination by ill food employees or unclean equipment and utensils.” Agency Response: The Agency agrees there are instances where inactivation of viruses would be appropriate label claims for sanitizers. These determinations will be made on a case
- by
- case basis. 5.2 Comment (0010): More detail of the key testing requirements for food contact surface towelettes is needed in the guideline. Agency Response: The Agency agrees and has expanded the test information guidance for food contact surface towelettes. 5.3 Comment (0010) (0015) : More detail of the key testing requirements for residual self
- sanitizing (dry) is needed in the guideline. Agency Response: The Agency agrees and has expanded the test information guidance for residual self
- sanitizing testing. 5.4 Comment (0015): The name for Salmonella typhi (ATCC 6359) has been changed to Salmonella enterica (AT CC 6359). Agency Response: Thank you for the correction. The Agency will make the change in the guidelines.

### 16

5.5 Comment (0015): The ATCC numbers for the test microorganisms for in
-tank sanitizers should be specified. Agency Response: The Agency agrees and will provide the ATCC numbers fo r all test microorganisms recommended in the test guidelines

. 5.6 Comment (0015): Previous Agency guidance lists Salmonella typhi as the test organism for food contact testing of halide products

. Table 1 of 810.2300 states test organisms are Salmonella typhi or Staphylococcus aureus

. Is the intent to provide two options of test organisms? Agency Response: Yes, the intent is to provide two options of test organisms since Salmonella typhi may be di fficult to acquire from ATCC. 5.7 Comment (0015): Sanitizers for Toilet and Urinal Bowl W ater
- Under the section describing the microbial counts of the treated bowl water, the Agency needs to define the three exposure intervals and provide clear guidance on how these were derived and what they equate to (e.g., duration, tablet lifespan, etc.). Agency Response: The Agency has expanded this section to include the number of flushes, test days, and test weeks (duration) for the test. The intervals were der ived when the protocol was first developed by the Agency and is intended to simulate flush activity in a normal household.