Overview
Provides confidence that there are no pests on the registered site when the commodity is vulnerable to infestation.
- Examples of a registered “site” include an entire farm, orchard blocks or greenhouses within a farm, packhouses and storage facilities. This measure incorporates Pest Free Place of Production (PFPP: one or more production units within a single premises) and Pest Free Production Site (PFPS: a defined portion of a premises), as defined in ISPM 10, but is not limited to production in The Menu of Measures.
- On-site surveillance is used to verify pest freedom, with requirements for corrective actions to eradicate the outbreak, or suspension of the site, if the pest is detected. Evaluating the efficacy of a Pest Free Site measure requires demonstrating that the surveillance design will provide the required confidence that the site is free of pests at times when the commodity is vulnerable to becoming infested.
- A Pest Free Site can be combined with additional supporting or dependent measures such as protected facilities, buffer zones, pest-free inputs and an Area of Low Pest Prevalence (ALPP).
- Assurance can be achieved through record-keeping and physical audit, or direct oversight, of key components of the Pest Free Site measure, by the NPPO or relevant authority of the exporting jurisdiction.
Evidence to support efficacy
Surveillance evidence is required prior to the establishment of a Pest Free Site to give confidence that it is pest-free, with ongoing surveillance required to maintain and verify pest freedom on the site. There is generally a zero tolerance for pest detection during the stipulated period within a designated site that is pest free. As a consequence, surveillance design, and the evidence supporting it, may need to be more stringent than that required for a Low Pest Prevalence Site (LPPS). An LPPS measure may be more appropriate where sufficient confidence in pest freedom can-not be achieved, even with no pest detections.
The surveillance must be able to detect pests already present within the site and, in most situations, pests entering the site. Appropriate survey methods will depend on their ability to quickly detect the pest at low densities (high detection efficacy). Survey methods may include growing season inspections and other detection methods like insect trapping, laboratory diagnostic testing and soil testing.
Supporting evidence is needed to demonstrate that surveillance design (e.g. sampling method, intensity, duration and frequency) will detect pests within the registered site with sufficient confidence (surveillance sensitivity). The level of required confidence in pest freedom may vary with the importance of the pest, as well as the likelihood that it will enter the site. The required surveillance sensitivity may therefore be lower within protected facilities (e.g. greenhouses), if the site is located within an ALPP, or if the pest is a poor disperser. This is because confidence in pest freedom increases if pests are unlikely to enter the site due to physical or geographic barriers. Evidence to support the efficacy of a surveillance design can be generated through modelling, empirical studies and reference to similar pests. Confidence can also be gained through trial implementation of a Pest Free Site measure across diverse sites.
Surveillance design should consider factors such as pest biology and detection methods, the likelihood of pest introduction to the site via natural or human-assisted dispersal pathways, site receptivity and attractiveness to the pest, detection latency (e.g. time required for symptoms to appear), and any potential interference from pest management activities (e.g. use of pheromone disruption technologies). For trappable pests, for instance, surveillance sensitivity is influenced by trap density and arrangement, lure attractiveness, and the dispersal ability of the pest. A perimeter-biased sampling design may be appropriate where pest entry is a concern. To give added confidence that a site is pest-free, surveillance may need to commence prior to the commodity becoming vulnerable to infestation.
If the target pest is detected, then the pest free status of the site may be withdrawn and the site suspended from trade. A corrective action may be permitted following pest detection, especially if the detection occurs prior to the commodity becoming vulnerable to the pest. A corrective action should be demonstrably fast-acting and not interfere with monitoring efficacy. Supporting evidence for the efficacy of any corrective actions aimed at re-establishing and verifying pest free status for the registered site will be required. Reinstating the status of the Pest Free Site will require evidence demonstrating that the pest is eradicated and absent from the designated site area for a certain period of time.
Applying the measure
How it is used
Providing sufficient confidence in pest freedom at the site level can be challenging. The use of a Pest Free Site measure is therefore typically restricted to pests that can be quickly detected through structured surveillance, and where there is a low likelihood of pests entering the designated site. For example, it could be applied to detectable pests that are poor dispersers, and to secure protected facilities such as a pest-exclusionary greenhouses within areas where the pest is expected to be rare.
During production a Pest Free Site measure can be applied to one or more premises or collection of fields, such as orchard blocks or greenhouses, that are operated together as a single production unit (PFPP: Pest Free Place of Production). It can also be applied to a defined portion of a Place of Production that can be managed as a separate unit, such as a defined greenhouse (PFPS: Pest Free Production Site). A Pest Free Site measure can also be applied in the same way to sites involved in post-production activities such as treatment, storage, packing, processing and logistics.
Use with other measures
On-site surveillance alone may not provide sufficient confidence in pest freedom, and so additional measures may be needed to ensure that the site is pest free. For example, a Pest Free Production Site may be located within an ALPP.
Pest avoidance measures can reduce the likelihood of pest presence or entry to the designated site. This can include limiting the use of Pest Free Site measures to areas (restricted to poor pest habitat) or times of the year (limit seasonal overlap) when the pest is rare or inactive.
Pest exclusion measures such as protected facilities, maintaining buffer zones, and pest-free inputs, can be used where there is a risk of the pest entering the Pest Free Site naturally or through human assistance. If buffer zones are required, then Pest Free Site measures will be restricted to areas where registered businesses can legally and practically implement them. Measures such as safeguarding (secure storage) and segregation may be required when the commodity is removed from the Pest Free Site to prevent subsequent infestation.
Independent measures such as kill treatments are generally not required.
Similar measures
A Pest Free Site differs from a PFA measure in terms of geographic scale, duration of pest free status, and outbreak consequences. Whereas a PFA is generally maintained over multiple years without interruption, the pest free status of a registered site may be maintained for only one or a few growing seasons. A key difference between a PFA and a Pest Free Site measure is that corrective actions and suspensions may only be applied to registered sites where the target pest is detected, provided that there is confidence that spread/contamination into other Pest Free Sites is not likely. Other registered sites exporting under the same export protocol are not necessarily affected.
Either protected facilities and Pest Free Site measures can be applied to ensure that a site such a greenhouse, packing facility or storage facility is pest-free. Both measures can also be combined, and in this case the Pest Free Site measure would support, or verify the protected facility measure.
A Pest Free Site and a LPPS can both have requirements for on-site surveillance and corrective actions, with a zero-tolerance for pest detections. However, an LPPS site is not assumed to be pest-free, even if no pests are detected.
Assurance of correct implementation
Registration of each pest free site and records of the application of key components of the PFS measure may be required. Depending on the method and the level of assurance required, this could include:
- records of the surveillance program (for example, trap placement, how frequently the traps were checked, any pest detections and diagnostic tests used)
- confirmation that outbreaks are triggered, managed and reinstated as agreed
- confirmation that additional supporting or dependent measures like buffer zones are correctly implemented
- requirements for consignment labelling to allow trace back to specific Pest Free Sites
- and the triggering and implementation of corrective actions, suspensions and reinstatements.
In some cases, physical inspection of the registered site and audit of the records can be conducted by authorised personnel at an appropriate interval, with oversight by the NPPO or relevant authority of the exporting jurisdiction. Pest freedom is more difficult to demonstrate than low pest prevalence, and so may require a greater level of assurance, and greater expectations from producers in terms of their management, technical and operational capabilities.