Measure category: pest exclusion

Risk reduction objective: pest exclusion

Measures in this category include:

  • Protected facilities
  • Safeguarding
  • Protected units
  • Segregation
  • Maintain buffer zone
  • Pest-free inputs

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

Overview of measure category

Partial or complete exclusion of the pest can be maintained during production and post-production. It can be achieved at the scale of the registered facility (e.g. protected cropping, secure processing and storage facilities), consignment level (e.g. safeguarding through secure packaging) down to the individual unit (e.g. bagging of fruit, wrapping of machinery). Pest exclusion measures often combine physical “infrastructure” (such as pest proof buildings) with management practices (e.g. to maintain the integrity of processing facilities).

Required proof of efficacy

Demonstration that both physical barriers and management practices are sufficient. This is often established based on the biology of the pest, for example to establish the maximum pore size of an exclosure. It can also be supported empirically through field surveys (comparing pest abundance inside and outside exclosures) or experimentally.

How these measures are certified

Most commonly certified through audit of structures and processes.

How these measures are used

Pest exclusion is relevant in some production systems, such as protected cropping and micro-propagation. Secure growing facilities are widely used as a measure for commodities that are grown commercially in that way. Partial exclusion, such as by netting and tunnels, might also contribute to risk reduction. We found no examples of those being stipulated as phytosanitary measures, although it may influence the assessment of unrestricted risk where the entire production system is grown in that way. Most protocols will have post-harvest pest exclusion measures, especially safeguarding.

Relationship with other measures

Depends on the measure.

Consignment stages where the measures can be applied

Protected facilitiesYesYesNo
Protected unitsYesYesNo
Maintain buffer zoneYesYesNo
Pest-free inputsYesYesNo

Measures in detail: pest exclusion

MeasuresRequired proof of efficacyHow the measure is certifiedHow the measure is usedRelationship to other measures
Protected facilities
Production and post-production (storage, processing, packing) facilities are designed and managed to exclude entry of pests that can subsequently infest the commodity.
The ability of both physical infrastructure and associated practices to exclude pests to the required extent needs to be established. This is often done through HACCP (Hazard Analysis and Critical Control Points). Surveys can be conducted where pest abundance is high outside of the facility. Other methods may be needed where external pest abundance is low, for example through experimentation or using data from other commodities grown in the same way but in higher pest abundance situations. Audit of physical structures and processesA common factor in PRA and a commonly used measure where production occurs in facilities that can be secured (e.g. protected cropping, micropropagation, ISPM10). Partial exclusion, such as by netting and tunnels, might also contribute to risk reduction, but is rarely quantified or considered when managing riskCan be combined with a pest freedom or low pest pressure measure (through monitoring and corrective action) or “inspect product and reject” measure to provide added confidence in the exclosure. For vectored diseases the action threshold may be higher for the vector than the disease
Physical barriers, with associated management practices, to prevent pests accessing the commodity (typically consignments). Intermediate between protected facilities and protected units. 
HACCP can be used to identify points of risk through the supply chain. Measures are often established biologically (e.g. to establish required pore sizes or commodity segregation requirements under storage conditions). In some cases, experimental studies may be needed to establish the level of risk, and the efficacy of specific measures under commercial conditions.Audit of physical barriers and processes.Safeguarding is almost universally required where there is a risk of secondary infestation along the production and supply chain. Can be a phytosanitary measure or commercial practice that contributes to PRA. This measure is functionally similar to protected facilities and protected units.
Protected units
Physical barriers, with associated management practices, to prevent pests accessing individual units of commodity.
Efficacy can be established through experimentation, although it does need to account for commercial conditions and likely environmental conditions that might be encountered.Audit of physical structures and processes.Rarely used, as probably not economic in many cases. Sometimes used in fruit production and has been used for shipment of machinery and other heavy equipment (to prevent hitchhikers).Tends to be combined with other measures that provide confidence that pest exposure is low, presumably because protection is not considered complete.
Actions to ensure regulated and unregulated commodity don’t mix in space or time, thereby preventing cross-contamination.
HACCP can be used to identify points of risk through the supply chain.Audit of processes.Can apply during production (for example to separate production of regulated and unregulated produce), but mostly applied post-production to prevent mixing through the supply chain. It can range from spacing commodity in storage to only allowing regulated commodity within a registered facilityOften used in combination with safeguarding to prevent post-production infestation from occurring.
Maintain buffer zones
Active establishment and maintenance of buffer zones around registered facilities or regions to provide spatial separation from unmanaged pest populations.
Demonstrating efficacy requires an understanding of dispersal risks, and the how immigration will affect exposure of commodities to pestsAudit of processes, and inspection of outcome.Used both during production and post-production (e.g. around storage and processing facilities). Unlikely to be used in isolation.Used to support the maintenance of pest exclusion (e.g. around registered facilities) and pest freedom or low pest prevalence (registered site or area-wide). Where buffer zones are extensive, they can be designated as an area of low pest prevalence.
Pest-free inputs
Ensuring (e.g. through sterilisation or cleaning) that equipment and inputs used in production, processing and packaging are free of pests.
HACCP can be used to identify points of risk through the supply chain.Audit of processes.A common requirement in micro-propagation, plant growing (for planting), the seed trade, and where plant pathogens can be transmitted to the commodity (e.g. fruit) through seeds or cultural practices.Often combined with other exclusion measures. Can contribute to maintaining pest free areas.

Key references

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