(1) Competent authorities must, subject to paragraphs (4) and (5), perform official controls once per year in the premises and, where applicable, in other locations used by authorised operators who produce or grow plants for planting in respect of which they issue, or intend to issue Northern Ireland plant health labels, where so required to meet the applicable requirements referred to in regulation 12 (substantive requirements).
(2) The controls must include inspections and, in the case of suspicion of risks to plant health, the sampling and testing referred to in regulation 15 (inspections and withdrawal of authorisation), to verify compliance with applicable requirements referred to in regulation 12.
(3) The controls must be carried out at the most appropriate time with regard to the possibility of detecting the presence of relevant pests or signs or symptoms of those pests.
(4) Competent authorities may increase the frequency of the official controls referred to in paragraph (1) of this regulation and regulation 15(1), if the risk so requires, taking into account at least the following factors:
(a) increased phytosanitary risks for the specific family, genera or species of the plants for planting produced in those premises and, where applicable, in other locations, where more than one control is necessary due to the pest biology or the environmental conditions;
(b) phytosanitary risks linked to the origin or provenance within Great Britain of particular plants for planting;
(c) number of production cycles in a year;
(d) history of compliance of the professional operator with the applicable provisions of the UK Plant Health Regulation, the Official Controls Regulation and these Regulations;
(e) available infrastructure and where the premises, and, where applicable, other locations used by the professional operator, are situated.
(5) Competent authorities may reduce the frequency of the official controls referred to in paragraph (1) to at least once every two years if—
(a) the risk so allows; and
(b) the professional operator concerned has complied with the applicable provisions of—
(i) the UK Plant Health Regulation;
(ii) the Official Controls Regulation; and
(iii) these Regulations.
(6) Premises and, where applicable, other locations used by authorised operators must be subject to at least one official control by the competent authorities in addition to the one referred to in paragraph (1) if they are the place of origin of plants for planting which—
(a) have been grown at least part of their life or have been located in a demarcated area established in accordance with Article 18(1) of the UK Plant Health Regulation, and
(b) can be expected to be infested by the pest for which that demarcated area had been established.
(7) That additional official control shall be carried out as close as possible to the point in time when those plants for planting are moved out of that demarcated area or from the infested zone to the buffer zone of that demarcated area.