Table 3.
Average prevalence of L. monocytogenes for each of 40 sites sampled 12 times over 2 years in each of three packinghouses.
| Area | Sub-area | Sample site description | Zone | Sample ID# | P1 | P2 | P3 |
|---|---|---|---|---|---|---|---|
| Lm prevalence (%) | |||||||
| Cold storage | Short-term and staging | Floor 1/3 | 3 | 01 | 33.3 | 8.3 | 8.3 |
| Floor 2/3 | 3 | 02 | 66.7 | 58.3 | 8.3 | ||
| Floor 3/3 | 3 | 03 | 33.3 | 25.0 | 8.3 | ||
| Floor crack/seam 1/2 | 3 | 04 | 16.7 | 0.0 | 16.7 | ||
| Floor crack/seam 2/2 | 3 | 05 | 41.7 | 16.7 | 8.3 | ||
| Foot of fruit storage bin | 3 | 06 | 8.3 | 0.0 | 0.0 | ||
| Long-term | Floor 1/3 | 3 | 07 | 16.7 | 16.7 | 0.0 | |
| Floor 2/3 | 3 | 08 | 16.7 | 33.3 | 0.0 | ||
| Floor 3/3 | 3 | 09 | 0.0 | 25.0 | 16.7 | ||
| Floor crack/seam | 3 | 10 | 16.7 | 33.3 | 0.0 | ||
| Foot of fruit storage bin | 3 | 11 | 0.0 | 8.3 | 0.0 | ||
| Packing line | Dump tank | Rim above water line 1/2 | 2 | 12 | 0.0 | 0.0 | 0.0 |
| Rim above water line 2/2 | 2 | 13 | 0.0 | 0.0 | 0.0 | ||
| Bin loading equipment | 2 | 14 | 0.0 | 8.3 | 8.3 | ||
| Bin unloading equipment | 2 | 15 | 8.3 | 0.0 | 0.0 | ||
| Interior of cull bin | 3 | 16 | 8.3 | 33.3 | 0.0 | ||
| Spray-wash | Spray or structural bar over brushes | 2 | 17 | 0.0 | 8.3 | 0.0 | |
| Drip pan | 3 | 18 | 16.7 | 8.3 | 0.0 | ||
| Scraper or structural bar under brushes | 2 | 19 | 25.0 | 0.0 | 0.0 | ||
| Floor directly below line | 3 | 20 | 33.3 | 91.7 | 0.0 | ||
| Fan-dry | Structural support/flow partitions above the line | 2 | 21 | 0.0 | 41.7 | 8.3 | |
| Drip pan | 3 | 22 | 8.3 | 66.7 | 0.0 | ||
| Scraper bars and drip pan funnel below line | 3 | 23 | 0.0 | 91.7 | 8.3 | ||
| Floor directly below the line | 3 | 24 | 25.0 | 100.0 | 0.0 | ||
| Wax | Structural support/wax spray bar over brushes | 2 | 25 | 0.0 | 33.3 | 8.3 | |
| Flow partition dividers/wax drip area | 2 | 26 | 8.3 | 66.7 | 0.0 | ||
| Drip pan/wax drip area | 3 | 27 | 16.7 | 100.0 | 16.7 | ||
| Structural support/wax drip area below the line | 3 | 28 | 0.0 | 91.7 | 16.7 | ||
| Floor directly below line | 3 | 29 | 8.3 | 100.0 | 16.7 | ||
| Potential cross-contamination sites | Catwalks adjacent to lines 1/2 | 3 | 30 | 8.3 | 58.3 | 8.3 | |
| Catwalks adjacent to lines 2/2 | 3 | 31 | 16.7 | 41.7 | 25.0 | ||
| Adjacent floor drains along the packing line | 3 | 32 | 33.3 | 91.7 | 0.0 | ||
| High traffic floor adjacent to packing line 1/2 | 3 | 33 | 8.3 | 33.3 | 0.0 | ||
| High traffic floor adjacent to packing line 2/2 | 3 | 34 | 0.0 | 33.3 | 0.0 | ||
| Forklift tine | 3 | 35 | 8.3 | 0.0 | 8.3 | ||
| Forklift wheel | 3 | 36 | 8.3 | 16.7 | 0.0 | ||
| Packaging line | Floor directly below sorting line | 3 | 37 | 0.0 | 16.7 | 0.0 | |
| Sorting line equipment | 2 | 38 | 0.0 | 33.3 | 0.0 | ||
| Floor directly below pack line | 3 | 39 | 0.0 | 16.7 | 0.0 | ||
| Line equipment | 2 | 40 | 0.0 | 8.3 | 0.0 | ||
0%, 
0–25%, 
26–50%, 
51–75%, and 
>75%.