NB/T 20259.4-2021 Bill of Quantities Valuation Specifications for Nuclear Power Plant Construction Project Part 4: Ventilation and Air Conditioning Installation Engineering (English Version)
2021NB/T 20259.4-2021 Bill of Quantities Valuation Specifications for Nuclear Power Plant Construction Project Part 4: Ventilation and Air Conditioning Installation Engineering
2014NB/T 20259.4-2014 Code of valuation on bill of quantities of nuclear power plant construction works.Part 4: Ventilation and air-conditioning