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Listeria monocytogenes (Lm) Regulations 

Introduction: 

 Listeria monocytogenes (Lm) is a widespread pathogen capable of surviving under 

various environmental conditions. 

 Lm is very tolerant of freezing, drying, salt, and heat, and will grow at temperatures as 

low as 31.3°F or as high as 113°F. 

 It can adapt to significant changes in pH values and reproduce at a pH as low as 4.39 

and as high as 9.4. 

 Lm can also reproduce with a water activity (aw) as low as 0.92. 

 Lm can produce a disease called listeriosis. 

 High risk groups include pregnant women and their fetuses, young children, the elderly, 

and immuno-compromised people. 

 A common link in Lm outbreaks is contamination of RTE products in the post-lethality 

environment prior to packaging. 

 The organism can also form a durable biofilm. 

FSIS has developed regulatory requirements specifically for controlling Lm in post-lethality 

exposed RTE products. In addition, the agency has developed Lm sampling programs as part of 

its public health strategy for protecting consumers against Lm. 

Establishment Responsibilities: An establishment that produces post-lethality exposed RTE 

meat and poultry products must maintain its facility in a sanitary manner. The sanitation 

program must be designed and implemented to prevent contamination of food contact surfaces 

(FCS) and adulteration of RTE product. 

Sampling Program: Under 9 CFR 430.4(b)(2)(iii)(A) and (3)(i)(A), establishments that produce 

post-lethality exposed RTE products are required to provide for FCS testing in the post-lethality 

processing environment to ensure that the surfaces are sanitary and free of Lm or indicator 

organism. 

Note: While sampling is not required under Alternative 1 or Alternative 2, Choice 1, FSIS 

recommends the establishment collect from each post-lethality exposed production line a 

minimum of 2 Lm FCS samples per year (every 6 months) under Alternative 1 and a minimum 

of 4 Lm FCS samples per year (quarterly) under Alternative 2, Choice 1. FCS sampling is 

required for Alternative 2, Choice 2 and Alternative 3. 

IPP Responsibilities for Verifying Compliance with 9 CFR Part 430.4: 

To verify compliance with 9 CFR 430.4: 

 IPP must be familiar with the establishment’s RTE products and processes. 

 IPP should ask the establishment which of the three Listeria control alternatives was 

chosen for each post-lethality exposed RTE product produced 

 IPP should verify that the establishment is meeting the requirements of the alternative it 

selected by performing the appropriate SSOP or HACCP tasks. If the establishment 

decides to produce different products using different alternatives, the inspector should 

verify that each post-lethality exposed RTE product meets the requirements for the 

alternative selected. 

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 In addition to verifying the effectiveness of the Listeria control alternatives selected, IPP 

will verify that the establishment is maintaining sanitary conditions sufficient to prevent 

product contamination, including Lm. Sanitation is the foundation for controlling Lm and 

without it, no alternative will successfully control Lm. 

Alternative 1 - 9 CFR 430.4(b)(1): 

Alternative 1 uses a post-lethality treatment (which may also be the antimicrobial agent or 

process) that reduces or eliminates microorganisms on the product AND an antimicrobial agent 

or process that suppresses or limits the growth of Lm. 

Alternative 2 - 9 CFR 430.4(b)(2): 

Alternative 2 uses either a post-lethality treatment (which may be the antimicrobial agent or 

process) that reduces or eliminates microorganisms on the product OR an antimicrobial agent 

or process that suppresses or limits the growth of Lm. 

Under Alternative 2, an establishment may select either Choice 1 or Choice 2 as follows. 

 Alternative 2, Choice 1 - The establishment chooses to use a post-lethality treatment (which 

may be an antimicrobial agent) that reduces or eliminates Lm on the product. 

 Alternative 2, Choice 2 - The establishment chooses to use an antimicrobial agent or 

process that suppresses or limits the growth of Lm. 

Alternative 3 - 9 CFR 430.4(b)(3): 

Alternative 3: involves the use of sanitation measures alone to prevent Lm in the 

processing environment and on the RTE product. There are separate FCS sampling 

requirements for deli meat and hot dogs produced under this alternative. 

Determining Compliance 

Gather Information 

IPP should use the GAD thought process to verify compliance with Alternatives 1, 2, or 3. 

Alternative 2 is based on the same requirements as Alternative 1 except that the establishment 

can choose to use only a post-lethality treatment (Choice 1) or an antimicrobial agent or process 

(Choice 2). When verifying compliance with Alternative 1 and Alternative 2 requirements, IPP 

should seek answers to the following questions: 

1. Is the post-lethality treatment (which may be an antimicrobial agent) incorporated in a 

HACCP plan? 

2. Does the establishment have scientific documentation supporting the effectiveness of its 

post-lethality treatment in accordance with 9 CFR 417.5(a)(2)? 

3. Does the establishment have validation data for the post-lethality treatment in accordance 

with 9 CFR 417.4? 

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4. Is the establishment implementing the post-lethality treatment as described in the HACCP 

plan? 

5. Has the establishment incorporated the use of the antimicrobial agent or process to 

suppress or limit the growth of Lm in its HACCP plan, its Sanitation SOPs, or a 

prerequisite program? 

6. Is the establishment using the antimicrobial agent or process as described in its HACCP 

plan, its Sanitation SOPs, or a prerequisite program, and can it scientifically support how 

the antimicrobial agent or process is being used? 

7. Has the establishment incorporated the use of the antimicrobial agent or process to 

suppress or limit the growth of Lm in its HACCP plan, its Sanitation SOPs, or a 

prerequisite program? 

8. Is the establishment using the antimicrobial agent or process as described in its HACCP 

plan, its Sanitation SOPs, or a prerequisite program? 

When verifying compliance with Alternative 2, Choice 2, or Alternative 3 requirements, IPP 

should seek answers to these questions regarding the establishment’s sanitation procedures. 

1. Has the establishment incorporated sanitation measures in a HACCP plan, SSOP, or 

other prerequisite program? 

2. Is the establishment’s food contact surface testing used to verify the on-going 

effectiveness of its sanitation procedures? 

3. Does testing of food contact surfaces in the post-lethality processing environment ensure 

that the surfaces are sanitary and free of Lm or of an indicator organism? 

4. Did the establishment identify the conditions under which it will implement hold-and-test 

procedures following a positive test of a food contact surface for Lm or an indicator 

organism? 

5. Did the establishment state the frequency with which testing will be done? 

6. Did the establishment identify the size and location of the sites that will be sampled? 

NOTE: establishments should identify all possible FCS sites (AskFSIS QA dated 2-17-12) 

7. Did the establishment include an explanation of why the testing frequency is sufficient to 

ensure that effective control of Lm, or an indicator organism, is maintained? 

If an establishment produces a RTE deli product or a hot dog product under Alternative 3, IPP 

should verify that the establishment: 

1. Effectively implemented corrective actions (with respect to sanitation after an initial positive 

result on a food contact surface in the post-lethality processing environment) by follow-up 

testing that includes targeted testing of the specific site on the food contact surface area and 

other sites as necessary to ensure effectiveness of the corrective actions. 

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2. Holds product lots that may have become contaminated by contact with the food contact 

surface when the establishment obtains a second positive test for Lm or an indicator 

organism during follow-up testing until the problem is corrected as indicated by negative 

follow-up test results. 

3. Sample and test product lots for Lm or an indicator organism using a sampling method and 

frequency that will provide a level of statistical confidence that ensures that each lot is not 

adulterated with Lm. 

4. Documents testing results. 

5. Reworks held product using a process that is destructive to Lm. 

Assess Information 

To answer these questions, IPP should: 

 Review the HACCP plan, 

 Review validation data (supporting documentation) for the post-lethality treatment, 

 Review HACCP records, 

 Review the Sanitation SOP and/or prerequisite programs associated with the use of the 

antimicrobial agent or process (as necessary), and 

 Review Sanitation SOP and/or prerequisite program records (as necessary). 

Determine Compliance 

IPP must determine regulatory compliance after all available information pertaining to the 

Listeria Control Alternative selected has been gathered and assessed. There is no 

noncompliance if the establishment has met all regulatory requirements. If the establishment 

has not met all regulatory requirements, the noncompliance should be documented on an NR 

under the appropriate PHIS task as described in FSIS Directive 5000.1 Rev. 5, citing the 

appropriate sections of 9 CFR 430.4(b), Part 417 for HACCP and prerequisite programs, and/or 

Part 416 for sanitation. IPP should verify that the establishment has taken effective corrective 

and preventive actions to bring itself into compliance with 9 CFR 430. Such actions may include 

a reassessment of the HACCP plan and the establishment’s choice of another alternative. 

Documentation and Enforcement 

If noncompliance with the Lm regulations is found, IPP are to issue an NR under the appropriate 

HACCP or SSOP task as described in FSIS Directive 5000.1, citing 9 CFR 430.4(b)(1), (2), or 

(3) and the appropriate sections of 9 CFR 417 or 416 if applicable. IPP are to verify that the 

establishment has taken effective corrective actions to bring itself into compliance with 9 CFR 

Part 430. Such actions may include, but are not limited to, a reassessment of the HACCP plan 

and the establishment’s choosing of another alternative or determining that the decisions it 

made in the hazard analysis regarding the use of a prerequisite program remain valid. 

If an establishment is producing post-lethality exposed products and has failed to meet any of 

the requirements of 9 CFR 430, IPP should contact the District Office through supervisory 

channels. A NOIE may be issued if the establishment HACCP system and/or SSOP is 

inadequate due to failure to meet the 430 regulations. 

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ATTACHMENT 1: CONTROL REQUIREMENTS for Listeria MONOCYTOGENES 

Requirements 

 Increasing Risk Levels and Frequency of FSIS Verification Testing 

ALTERNATIVE 1 ALTERNATIVE 2 ALTERNATIVE 3 

Post-lethality 

Treatment AND 

Antimicrobial 

agent or Process 

Post-lethality Treatment OR 

Antimicrobial agent or Process 

Sanitation and Testing 

Program 

Choice 1: 

Post-lethality 

Treatment 

Choice 2: 

Antimicrobial 

Agent or Process 

Non-deli, 

Non-hotdog 

Deli or hotdog product 

Validate effectiveness of post-lethality treatment (PLT). Must be 

included as a CCP in the establishment’s HACCP Plan and should show at 

least a 1-log reduction in Lm prior to distribution of the product into 

commerce 

X X 

Document effectiveness of antimicrobial agent or process: Must be 

included as part of the establishment’s HACCP, Sanitation SOP, or Prerequisite Program and should demonstrate no more than 2-logs growth of 

Lm over the estimated shelf life. 

X X 

Sanitation Program Requirements 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

X X X 

Testing food contact surfaces (FCS) in the post-lethality processing 

environment for Lm or an indicator organism. 

X X X 

State testing frequency. X X X 

Identify size and location of sites to be sampled. X X X 

Explain why testing frequency is sufficient to control Lm or an indicator 

organism. 

X X X 

Identify conditions for Hold-and-Test, when FCS (+) for Lm or an indicator 

organism. 

X X X 

Additional Sanitation Program Requirements 

Follow-up testing to verify corrective actions are 

effective after 1st FCS (+) for Lm or an indicator organism. Includes testing 

of targeted FCS as most likely source and additional testing of the 

surrounding area. 

X 

If follow-up testing yields 2nd FCS (+), hold products that may be 

contaminated until problem is corrected as shown by FCS (-) in follow-up 

testing. X 

Hold and test product lots using a sampling plan that provides statistical 

confidence that the lots are not contaminated with Lm or an indicator 

organism. Release, rework or condemn products based on results. 

Document results and product disposition. X 

Establishments in all three alternatives must maintain sanitation in 

accordance with 9 CFR 416. 

X X X X X 

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Definitions Related to Listeria monocytogenes (Lm) 

9 CFR 430.1 provides a several definitions that are specific to ready-to-eat (RTE) products. 

Two RTE product definitions are deli products and hotdog products. 

A deli product is an RTE meat or poultry product that is typically sliced, either in an official 

establishment or after distribution, and assembled in a sandwich for consumption. 

A hotdog product is an RTE meat or poultry frank, frankfurter, or wiener product with a 

standard of identity defined in 9 CFR 319.180 and 319.181. 

Note: A risk assessment performed jointly by FSIS and the FDA indicated that on a per serving 

basis, deli meats and hotdogs (not reheated) posed the greatest risk of illness and death from 

Lm. 

A lethality treatment is the initial process RTE meat and poultry products undergoes to 

eliminate or reduce the number of pathogenic microorganisms on or in a product. Examples of 

lethality treatments that will make an RTE product safe for human consumption include cooking 

or the application of an antimicrobial agent or process that eliminates or reduces pathogenic 

microorganisms. 

The post-lethality processing environment is the area in an establishment into which product 

subjected to an initial lethality treatment has been routed. The product may be exposed to the 

environment through slicing, peeling, re-bagging, cooling semi-permeable encased product in a 

brine solution, or other procedures. 

Post-lethality exposed product is RTE product that comes into direct contact with a food 

contact surface in the post-lethality processing environment after an initial lethality treatment. 

Only post-lethality exposed RTE products are subject to 9 CFR 430. 

The following three terms are associated with the three Listeria control alternatives used to 

control or prevent Lm in an RTE product in the post-lethality environment: 

• Post-lethality treatment (PLT) - an additional lethality treatment, following the initial lethality 

treatment, applied to the final product or sealed package of product to reduce or eliminate the 

risk of Lm contamination during post-lethality exposure. Examples of post-lethality treatments 

include steam pasteurization, hot water pasteurization, radiant heating, and high pressure 

processing (HPP). Some antimicrobial agents may also function as post-lethality treatments. 

• Antimicrobial agent - a substance in or added to an RTE product that suppresses or limits 

growth of Lm in the product throughout the shelf life of the product. Examples of antimicrobial 

agents used in RTE products are sodium lactate, potassium lactate, and sodium diacetate. 

For additional antimicrobial agents see FSIS Directive 7120.1. 

• Antimicrobial process - an operation (e.g., freezing) applied to an RTE product that 

suppresses or limits the growth of Lm in the product throughout the shelf life of the product. 

Examples include: Drying and fermenting 

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While not defined in 9 CFR 430.1, indicator organism is defined in 9 CFR 430 as bacteria 

used to determine if the sanitary conditions of food processing equipment, production areas, or 

storage rooms allow for the presence of objectionable microbes (i.e., pathogens). 

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