Field Notes
EN 12845 Hazard Classes and Building Types (LH, OH, HHP, HHS and FH)
The four hazard groups, design densities, sector-by-sector building lists, Material Factor analysis and the new FH conversion matrix.
Field Notes
ESFR and CMSA Prohibitions in EN 12845: FH Hazard Classes and Design Limits
Why EN 12845-2 prohibits ESFR and CMSA in FH3 to FH5, the technical reasoning, and the HHS1-HHS3 design requirement in FH1 and FH2.
Field Notes
EN 12845-2 ESFR/CMSA Design and Minimum Operating Pressures (FH1/FH2)
K-factor and minimum operating pressure tables, the special-condition 9 and 10 sprinkler route, wet and dry CMSA options and layout limits.
Field Notes
EN 12845-2 ESFR/CMSA Design Examples: Sprinkler Selection by Ceiling Height (7–17 m)
Dozens of worked ESFR and CMSA designs by ceiling height for process and storage occupancies, based on EN 12845-2 Tables 7 to 21.
Field Notes
TS EN 12845 Sprinkler Design Criteria Guide: CMDA, ESFR and CMSA
Design densities, areas of operation, K-factor and pressure tables, spacing, deflector distances and obstruction rules in one reference.
Field Notes
CMDA and CMSA Sprinkler Technologies: An NFPA 13 (2025) Comparison
Design approach, K-factor limits, roof slope constraints, droplet characteristics and hydraulic calculation methods compared.
Field Notes
Maximum Ceiling Heights for Sprinklers per NFPA 13
Ceiling height limits by K-factor for non-storage and storage occupancies, the 9.1 m rule and minimum K-factor by design density.
Field Notes
Relief Valves and Auxiliary Reservoirs on Wet Sprinkler Systems per NFPA 13
1/2 inch relief valves and auxiliary air reservoirs, thermal expansion, the 175 psi limit, antifreeze expansion and PRV outlet relief.
Field Notes
Setting Fire Pump Pressures at Commissioning — The NFPA 20 Pressure Cascade
Controlled filling, air venting, water hammer prevention and the jockey stop/start and main pump start cascade, with a worked example.
Field Notes
Filling and Pressurising a Fire System Before First Operation — NFPA 20 and 24
Flushing flow rates, slow filling, air venting, priming, hydrostatic testing and the critical prohibitions during first fill.