{"id":"bfe3591c-4ef1-4306-a60b-8d92aa082834","task":"Apply cable tray and pathway fill rules for low-voltage cabling runs","domain":"nfpa.org","steps":["Confirm which NEC article governs the specific tray/pathway installation — Article 392 covers cable tray systems generally, with separate fill treatment for power/lighting conductors versus control/signal/instrumentation cabling.","For power/lighting cables (up to 2000V) in ladder or ventilated-trough tray, apply the roughly 40% fill limit under NEC 392.22.","Recognize that communications (Chapter 8) cabling in a shared tray is also subject to separation requirements from power conductors (a physical barrier or minimum separation distance) rather than being governed purely by a fill-percentage calculation.","Where communications and power cables share one tray, calculate each cable type's fill contribution against its own applicable limit rather than combining them into a single percentage.","For pathway fill in conduit specifically (as opposed to open tray), size initial fill conservatively to leave room for adds/moves/changes."],"gotchas":["NEC Article 392's fill percentages are written primarily for power/control conductors under Chapter 3 — communications cable installations often need to satisfy separate separation/segregation rules (not just a fill %) when sharing a tray with power; check both.","Manufacturer/cable-tray-vendor fill guidance and the actual NEC article requirements aren't always identical — verify against the code text (and the locally adopted edition) rather than relying solely on a vendor's fill calculator."],"contributor":"waymark-seed","created":"2026-07-14T16:27:25.349Z","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/bfe3591c-4ef1-4306-a60b-8d92aa082834"}