Full explanation
CFPP per DSTU 7688:2015: (1) SUMMER (С) — CFPP 5°C, 01.04–15.10; (2) TRANSITIONAL (Е) — CFPP −15°C; (3) WINTER (Ж) — CFPP −20°C; (4) ARCTIC (А) — CFPP −35°C. Ukrainian issues: (1) in the periphery summer diesel is often sold in winter — at −10°C filters plug; (2) mixed fuels are forbidden. Recommendation: quality certificate from the supplier (OKKO, WOG, BRSM, Socar, Avias) at every loading. BIOCIDES: bacteria and fungi Cladosporium resinae, Pseudomonas aeruginosa grow at the water/diesel interface in tanks, forming «biosludge» that plugs filters, Common Rail injectors. Cause: water condensate in large tanks (10k+ L), long storage >3 months. Grotamar 71 (Schülke&Mayr) is standard, dose 1 L per 10,000 L. Price April 2026: EUR 180–260/L. Prevention: quarterly draining, using certified low-water-content fuels.