SIR, – Fuel suppliers, distributors and fuel tank suppliers have all known that the British standard (No 2869) for non-road diesel was revised in 2006 to allow the addition of fatty acid methyl esters (FAME).

They also know that in 2011 an EU directive was implemented, so changes by all suppliers should have been implemented either 13, or at least eight years ago to ready us for a smooth transition. Given their inactivity you have to question what actions have been taken since April, 2018, when biofuel targets of 7.25% were announced to be followed by rises to 8.5% and 9.75% in 2019 and 2020, respectively.

The advice in last week's article: prudent to keep a supply of spare filters for machinery and storage tanks, or clean your tank out at every refill (for which specialist cleaners can only give a 95% guarantee) ,or buy a variety of additives, all add to farmers costs and are impractical. Where is the advice to claim against suppliers for failing to supply products in line with regulations.

When you go to your local shop to buy food, it all has to have standards and a sell by date. Why are our fuel suppliers any different?

Andrew Thomson

South Carse of Coldoch,