IPM Action Thresholds for an Account

Why this matters

Without written thresholds, a commercial account runs on one of two bad habits. Either the tech treats on the calendar whether anything is there or not, which piles pesticide into a food plant for no reason and reads badly to an auditor, or he waits until the manager complains, by which time a few roaches at the dish machine are a few hundred behind the line. An action threshold is the agreed count that moves the program from watching to inspecting, and from inspecting to acting. It turns monitoring data into decisions anyone can check. The principles of IPM are in Integrated Pest Management Reference; this card shows how to write thresholds for one account and run the data against them.

A threshold is an agreement, so it is written down

The numbers below are not a standard and not a label direction. They are what the service company and the client agreed for this facility, signed and dated, and they change only by the same process. Three reasons they belong in writing:

• They set expectations both ways. The client knows a single roach on a storage monitor triggers an inspection, not a treatment, and does not call that a failure. The tech knows he cannot let two roaches in food prep ride to the next visit.
• They are what an auditor tests. Food-safety audit schemes expect a documented program with defined responses; a threshold table plus records showing it was followed is the evidence.
• They keep treatment tied to need. A threshold never authorizes a product or a site. When a threshold says act, the action is chosen from sanitation, exclusion, trapping and, where warranted, a pesticide applied per the product label in a site the label permits.

The threshold table for one account

The account: a wholesale bakery with a production floor, a dry-goods warehouse, an office and break room, and a loading dock. Service every two weeks.

ACTION THRESHOLDS   Northside Bakery   signed 03/12
counts are per two-week service interval
-----------------------------------------------------
ZONE / PEST        INSPECT AT         ACT AT
-----------------------------------------------------
PRODUCTION (food prep)
 German roach      1 on any monitor   2 or more in
                   or 1 sighting      zone, or any
                                      nymph
 Rodent            any sign           any capture or
                                      live sighting
STORAGE (dry goods)
 German roach      2 in zone          4 in zone
 Stored prod moth  5 on any phero     15 on any
                   trap               phero trap
 Rodent            any sign           any capture
OFFICE / BREAK ROOM
 German roach      3 in zone          6 in zone
 Ants              trail sighted      trail on 2
                                      visits running
EXTERIOR
 Rodent stations   feeding in 2 or    feeding in 4 or
                   more stations      more stations
-----------------------------------------------------
"in zone" = monitor captures plus staff sightings

How to read it

Unit of analysis. Every count is per two-week service interval. "On any monitor" is per device; "in zone" is the total of monitor captures plus logged staff sightings across the whole zone. Mixing the two is the most common error: four roaches spread across four production monitors is one per monitor, which on a per-device reading would only trip inspection, but four in zone trips the act threshold.

The Boolean. Where a cell lists two conditions with "or", either one alone triggers the tier. "1 on any monitor or 1 sighting" means a single sighting with clean monitors still triggers an inspection.

Inspect, then act. Inspection means a focused look at the triggering spot and its surroundings to find the cause: a harborage, an entry point, a sanitation failure, an infested ingredient. Acting means doing something about the cause, with a pesticide only where the inspection says it is warranted and the label permits it.

Why sensitive zones get lower numbers

Production is the zone where a pest touches product, so its thresholds sit at the floor: one roach triggers inspection, and any rodent sign at all is the inspect tier, with any capture or live sighting the act tier. Storage tolerates a little more because product is packaged, but stored-product moths get their own row because they live in the ingredients themselves. The office sits highest because no product is there and the main cost of a few roaches is a complaint, not a contaminated batch.

The same logic drives thresholds at schools, healthcare facilities and childcare centers, where the occupants are the sensitive part. There, thresholds tend to be low for pests that bite or spread disease and the response leans hard on non-chemical action first. Several states have laws requiring IPM programs, notification or posting before applications at schools or childcare facilities; check your state lead agency for what applies to the account. See related: Sensitive Account Service: School or Healthcare.

Where the law sets the floor, not the contract

A contract can set the count that triggers a visit; it cannot make pest contamination of food acceptable. Under the federal Food, Drug, and Cosmetic Act, Section 402(a)(4), food is adulterated if it is prepared, packed or held under insanitary conditions where it may have become contaminated with filth, and rodent and insect evidence in a food plant is exactly that kind of condition. That is why the production row's rodent line has no tolerance at all, and why a rodent capture there is reported to the plant's food-safety lead the same day rather than written up at the end of the visit. State and local health codes add their own requirements for retail food establishments. The plant's food-safety team owns product decisions (hold, inspect, discard); the tech's job is to report promptly and accurately what was found and where.

Worked example: one interval run against the table

The tech arrives for the scheduled visit and pulls the counts since the last one.

Production. Four monitors read 0, 1, 0 and 1 roach (adults). The sighting log has no production entries. Zone total: 2.

• Per device: two monitors at 1, so the inspect tier is triggered.
• In zone: 2 meets "2 or more in zone", so the act tier is triggered too.

He inspects both monitor locations and finds roaches in a gap behind a mixer's control box, a classic warm harborage. Action: the gap is noted for maintenance to seal, and a crack-and-crevice placement suited to a food area goes into the harborage per the product label. Electrical caution: the gap is at an energized control box, so the placement stays at the frame gap, nothing goes into the box, and if the harborage is inside the enclosure the work stops until the plant's maintenance staff isolate the equipment under the plant's lockout procedure and prove it dead.

Storage. No roaches, no rodent sign. One pheromone trap shows 7 Indian meal moths; the other three show 0, 1 and 2.

• 7 is at or over 5, so inspect; under 15, so not act.

He inspects the dry-goods racks near the 7-count trap and finds webbing in a torn, outdated bag of flour. The action at the inspect tier is the client's: remove and dispose of the infested product and tighten stock rotation. No pesticide; the inspection found a cause that sanitation fixes.

Office and break room. Monitors behind the vending machine and the coffee station show 3 roaches total. No staff sightings.

• 3 meets the inspect threshold; under 6, so not act.

He inspects and finds roaches in the vending machine's warm underside. He records it and asks the client to contact the vending company, because the machine belongs to them.

Exterior. Twelve rodent bait stations; feeding in 3.

• 3 is at or over 2, so inspect; under 4, so not act.

He checks the interior walls nearest the three stations for rodent sign and finds none, and checks the dock door seals, which are intact. Station servicing follows Rodent Bait Station Placement and Servicing.

The tally. Four zones checked, four inspect tiers triggered, one act tier (production roaches). One pesticide placement made, in the one zone where both the threshold and the inspection called for it. Every threshold decision and its result go on the service report beside the counts that triggered it.

What would change the outcome. If the production monitors had read 1, 0, 0, 0, the zone total would be 1, inspection only, and the mixer harborage might still be found and sealed without any placement. If the 7-moth trap had read 15, the storage row would reach the act tier and the response would add a broader search of the warehouse for other infested lots.

Writing thresholds for a new account

Start from a baseline: two or three intervals of monitoring before setting numbers, so the thresholds reflect what this facility normally shows. Set production and other product-contact zones at or near the floor. Write the unit of analysis on the table itself. Review the table with the client at least once a year and whenever the facility changes (new line, new storage, a renovation), and re-sign it.

Where thresholds go wrong. Numbers copied from another account with a different layout. Thresholds that are never compared against the data, so the table exists only for the auditor. A threshold that triggers so often nobody responds anymore, which means it is set below the facility's normal background and should be reviewed with the client, not ignored.

References

• See related: Integrated Pest Management Reference
• See related: Sensitive Account Service: School or Healthcare
• See related: The Commercial Pest Sighting Log
• See related: Commercial Food-Handling Facility Audit Requirements (AIB, SQF, BRC)
• See related: Rodent Bait Station Placement and Servicing
• Federal Food, Drug, and Cosmetic Act, Section 402(a)(4) (adulteration, insanitary conditions)