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Web Content Viewer (JSR 286)


Web Content Viewer (JSR 286)


Web Content Viewer (JSR 286)


Web Content Viewer (JSR 286)


Web Content Viewer (JSR 286)


FSIS Microbiological Testing Program for Ready-to-Eat (RTE) Meat and Poultry Products: Timeline (Changes to the program)

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On January 2, 2019, FSIS laboratories began using the 3M™ Molecular Detection System for initial screening of regulatory samples for Salmonella and Listeria monocytogenes (Lm), following the completion of an evaluation of commercially available rapid pathogen screening technologies.  Further, on March 15, 2019 FSIS suspended the routine use of PFGE for the characterization of Salmonella; whole genome sequencing (WGS) is being used as the primary tool for characterization of Salmonella isolates. The decision to characterize these isolates via WGS was taken in coordination with federal and public health partners at the Centers for Disease Control and Prevention (CDC) PulseNet network.


In coordination with CDC PulseNet, FSIS suspended PFGE for Lm and as of January 15, 2018, started generating Lm characterization through WGS only. 


On October 1, 2016, FSIS made a change to the algorithm used for scheduling RTEPROD_RISK and RTEPROD_RAND samples and also changed the allocation of samples to each of the programs that is further described in Random and Risk-based Scheduling Criteria for the RTE Product Routine Sampling Program. This was done for two reasons: 1) To properly target product groups based on historical sampling data, and 2) To use the alternative identified by the establishment to control Lm in the sampling methodology.


RTEPROD_RAND–Random sampling of Lm and Salmonella in RTE products for both post-lethality exposed and non-post-lethality exposed products (e.g., cook-in bag products).

RTEPROD_RISK–Risk-based sampling of post-lethality exposed RTE products for Lm and Salmonella based on established product types and processing practices.

  • Under RTEPROD, FSIS collects 2 pounds of product. FSIS labs analyze a 25g sample for Lm and another 325g sample for Salmonella. If any positive isolates are confirmed, FSIS labs then enumerate using MPN on the sample reserve and perform PFGE on the positive isolates. In August 2013, FSIS replaced the ALLRTE and RTE001 sampling projects with RTEPROD_RAND and RTEPROD_RISK respectively.

RLMPRODC–Routine risk-based sampling project designed to obtain intact RTE food product samples for Lm collected from a production line that is in operation at the establishment.

  • In January 2013, FSIS replaced the RLMPROD sampling project with RLMPRODC. Under RLMPRODC, FSIS collects five 1 pound samples within a sample unit. FSIS labs remove five 25g sub-samples from each unit, which are composited at the testing laboratory into a single test sample. FSIS increased the number of samples from 3 to 5 when the RLMPRODC sampling project was implemented.


RLMENVC–Routine risk-based sampling of non-food contact environmental surfaces (RLMENVC) for Lm in RTE production areas having indirect (e.g. mop handles or outer garments that may be handled by a person who may touch RTE product) or no contact (e.g., floors, drains, walls, air vents, overhead structures) with the sample product lot. The five environmental swab samples are composited at the testing laboratory into a single test sample rather than analyzing each individually.

  • FSIS transitioned from collecting three non-composited environmental samples to collecting five samples that were composited into one sampling unit (see definition in RLMENVC).
  • FSIS changed the number of swab samples collected to increase the number of establishments scheduled each month from 15 to 45.


FSIS implemented RLm, phase 2 of the Lm risk-based sampling program. RLm included sampling of products, product contact surfaces, and environmental surfaces in conjunction with a comprehensive Food Safety Assessment (FSA). FSIS Directive 10,240.5 provided direction to Enforcement, Investigations, and Analysis Officers (EIAOs) and Public Health Veterinarians (PHVs) trained in the EIAO methodology for collecting samples under the RLm sampling project. RLm samples are analyzed only for Lm.

In calendar year 2006, FSIS discontinued the RTERISK1 project and RTE001 continued in its place.

RLMPROD–Routine risk-based sampling project designed to obtain intact RTE food product samples for Lm collected from a production line that is in operation at the establishment.

RLMCONT–Lm routine risk-based sampling project designed to obtain food contact surface samples in the RTE production areas that have direct contact (e.g., conveyor belts, cooler storage racks, luggers, slicers, peelers, loaders, table tops).

  • Brine or chill water samples are considered to be contact surface samples, if they come in direct contact with exposed product, or the product is in a semi-impermeable casing.

RLMENVR–Routine risk-based sampling project designed to obtain for Lm selected from brine or chill water that does not come into direct contact with post-lethality exposed RTE product.

  • Brine or chill water is considered to be environmental samples if the product is in an impermeable casing or otherwise packaged.


RTE001–Lm and Salmonella sampling project used primarily to verify that establishments producing post-lethality exposed meat and poultry products are controlling the pathogens and are in compliance with the zero tolerance requirements of 9 CFR 430 for Lm.


ALLRTE–Lm and Salmonella sampling project designed to obtain random samples across all RTE products and throughout establishments producing a RTE product, regardless of the risk or product type.

RTERISK1– Product selection was based on the risk-based guidance provided in FSIS Directive 10,240.4 in October 2003. However, once a RTERISK1 sample was scheduled, inspection program personnel were instructed to collect only Alternative 3 products if they were available. (Definitions for RTE Alternatives 1, 2, and 3 can be found in 9 CFR 430.4.)


FSIS began target sampling of RTE products. Under FSIS Directive 10,240.3, inspection program personnel received a form requesting a sample under the target project. The form included instructions to collect a RTE sample based on priority: high (e.g., deli meats) and medium (e.g., franks/hot dogs). During this process, inspection program personnel designated whether the product was a targeted product or low-targeted product.


FSIS discontinued its RTE testing program on selected product categories and began sampling based on Hazard Analysis and Critical Control Point (HACCP) processing categories identified in 9 CFR 417.2 that apply to RTE products. This transition is detailed in FSIS Directive 10,240.2, Microbial Sampling of Ready-to-Eat (RTE) Products.

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Last Modified Mar 18, 2020