The gradual annual reduction in total dose was requested by companies that hold approvals for formulations as part of the CIPC stewardship process and was agreed with the Expert Committee on Pesticides.
The new Chemicals Regulation Directorate-approved limits are 30g per tonne for the fresh market and 50g per tonne for processing. Latest time of application is 14 days before removal from store for sale or processing.
Best practice, in line with Red Tractor Farm Assurance and the NAAC applicator group, permits just one application in cold stores (under 5 degsC), early in storage.
Stewardship Group secretary Adrian Briddon said: "From 2017 it is expected that new product labels will permit a total dose of no more than 36g per tonne, with conditions under which this may be applied more strictly controlled on labels."
And he warned: "Even modest doses of around 10-14g per tonne applied under conditions where best practice modifications have not been adopted will increase the risk of a Maximum Residue Level exceedance. Now more than ever, it is critical that users adopt best practice."
The group was formed to reduce CIPC residues in the 3.5 million tonnes of stored potatoes treated each year, to safeguard its availability for future use. Its guidance can be found online at www.BeCIPCcompliant.co.uk.