Measure category: remove infested commodity units

Risk reduction objective: reduce infestation rates

Measures in this category include:

  • Symptom grading
  • Risk profiling

Note that this resource is a working draft, which is currently being reviewed and updated in collaboration with biosecurity specialists.

Overview of measure category

Reduces infestation rate by removing commodity units that are or could be infested. Can be undertaken during production, post-production and post-border. Inspection is mostly done visually, although non-destructive detection technologies can also be used.

Required proof of efficacy

Demonstration that grading or risk-profiling will reduce infestation rates in the consignment to acceptable levels. This includes determination of detection efficacy for relevant life stages and infestation levels.

How the measures are certified

Audits of processes and outcomes.

How the measures are used

Limited to pests where high-risk units can be readily identified and then removed or treated.

Relationship with other measures

Removing infested commodity units has similarities to measures that remove infested consignments but differs in its goal. By removing infested commodity units it reduces the infestation rate within the consignment. In contrast, measures that remove infested consignments require subsampling of the consignment, with the consignment being rejected if sufficient infested units (typically one) is found. As a result, the later typically requires more careful inspection and diagnostics.

Consignment stages where the measures can be applied

Symptom gradingYesYesNo

Measures in detail: remove infested commodity units

MeasureRequired proof of efficacyHow the measure is certifiedHow the measure is usedRelationship to other measures
Symptom grading
Removing commodity units that show evidence of being infested, either directly (through detecting the pest or its characteristic damage) or indirectly through the presence of more generic symptoms. In some cases, it requires the commodity to be inspected in a specific way to maximise the likelihood of pest detection.
Need to show that symptom grading is sufficiently sensitive when it comes to detecting and removing infested commodity units. This can initially be determined experimentally, then confirmed under commercial conditions. Detection efficacy will depend on the pest, the pest stage that needs to be detected, the commodity and the detection method (e.g. visual, destructive or optical sensors).Audits of processes and of the post-graded commodity against grading requirements.Can be an important phytosanitary measure for pests where detection probabilities are high, such as insects that are external feeders on fruit. In obvious cases it may not be specified as a phytosanitary measure. Optical scanning technologies offers the potential for automated detection of pests or pest symptoms on the commodity.Like inspect product and reject, but detection of an infested unit results in its removal, with no consequences for the broader consignment. Symptom grading and quality grading based on quality specifications (to minimise vulnerability of the commodity) is often done simultaneously but reduces risk in different ways. Symptom grading remove units that appear to be infested whereas quality grading removes units that belong to quality categories that have a higher risk of being infested irrespective of whether they show signs of being infested.
Risk traits rather than pest symptoms, are used to identify, remove or treat units that are most likely to be infested.
Needs to demonstrate the link between risk attributes and likelihood of infestation. The trade-off between pest risk and resourcing may also need to be considered. Demonstration of efficacy of the treatment or response if high-risk unit is found.Normally conducted by the receiving NPPO.Most commonly used post-border where “units” (e.g. passengers and their luggage, shipping containers, ships, aircraft, [PEQ?]) can be singled out based on attributes that affect the likelihood of being infested or of carrying a pest and treated accordingly. It is most useful where the infestation risk across “units” within a “consignment” (e.g. passengers on a plane) is not strongly dependent. Passage of the “unit” is normally permitted after treatment of the risk.Risk attributes may also be used to guide measures that remove infested consignments, but there the consequence is on the consignment (e.g. ship load of shipping containers) rather than the unit. Differs to specifying poor host or carrier as in this case passage of high-risk items is still permitted following inspection.

Key references

  • Key references will be determined through consultation with biosecurity specialists and added here in the coming months.