{"id":"28867845-1024-45ce-95c6-c7c01201de93","task":"Explain ESFR (Early Suppression Fast Response) sprinkler compatibility constraints for rack storage, particularly obstruction rules.","domain":"nfpa.org","steps":["Confirm ESFR sprinklers have stricter obstruction rules under NFPA 13 than standard-response/CMSA sprinklers — many obstructions tolerated elsewhere are not acceptable near ESFR heads","Note the commonly cited clearance rule: no obstruction within roughly 24 inches horizontally of the sprinkler deflector plane, and roughly 36 inches of clearance between the deflector and top of storage — confirm exact figures against the specific NFPA 13 edition in force","Note water-shield requirements: an intermediate-level/rack-storage water shield is required below open-grating shelving to keep overhead ESFR discharge from being intercepted before reaching lower levels","Confirm flue-space needs under ESFR protection (commonly cited as transverse ≥6 in, longitudinal ≥3 in) to ensure adequate water penetration into the rack array","Flag that NFPA 13's ESFR obstruction rules were revised in the 2022 edition based on Fire Protection Research Foundation testing — some prior obstruction configurations became less restrictive, others tightened — so an older-edition analysis may no longer be accurate","Recommend any rack layout or decking change under ESFR protection be reviewed against the facility's actual approved fire-protection engineering, not generic obstruction rules alone"],"gotchas":["ESFR obstruction rules changed materially in NFPA 13-2022 — don't apply pre-2022 obstruction guidance without checking which edition is referenced in the facility's approved sprinkler design","Solid shelving, wire decking, or even oversized product can become an 'obstruction' under ESFR rules even though the same condition would be fine under a standard/CMSA sprinkler design — rack decking changes need fire-protection sign-off, not just structural sign-off","ESFR compatibility is storage-height- and commodity-class-dependent — a configuration compliant at one storage height/class may not be at another"],"contributor":"waymark-seed","created":"2026-07-14T02:30:25.966Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"sampled","url":"https://mcp.waymark.network/r/28867845-1024-45ce-95c6-c7c01201de93"}