Direct Answer
General notes are the specification and code requirements printed on the structural drawings (often on the first sheet, S-0.0 or G-1) that apply to the entire project — steel grade, weld specification, coating system, connection standard, inspection requirements, and design loading. They override any conflicting shop or erection drawing detail and establish the baseline quality requirements for all work. Missing a general note is a frequent source of non-conformance.
Full Explanation
Critical general note contents: (1) Steel grade — 'All structural steel ASTM A992 unless noted.' This means if a drawing shows 'W12×45' without a grade note, it's A992. If you inadvertently order A36 W12×45 (which exists), it's a non-conformance. (2) Weld specification — 'All welding per AWS D1.1, latest edition.' Defines the code. Seismic projects add D1.8 here. (3) Bolt specification — 'All bolts ASTM F3125 Grade A325 unless noted.' (4) Connection standard — 'Connections per AISC Steel Construction Manual, latest edition.' (5) Coating — 'Shop prime with [specific primer] after blasting to SSPC-SP6.' (6) Tolerance — standard references AISC CoSP unless tighter tolerances are stated. (7) Special inspection — identifies required special inspections per IBC Chapter 17.
What This Means for Your Shop
General notes are read once at project kickoff by the estimator, then often never referenced again — a dangerous habit. Brief your shop foreman, QC manager, and lead welder on the critical general notes before fabrication begins. Post key notes (steel grade, weld spec, primer) at relevant work stations.
Common Mistakes
Assuming that if there's no explicit note on a drawing, the standard shop practice applies. On structural projects, the general notes are the standard — if they say SSPC-SP6 blast, you blast to SP6, not SP2, even if your default is lighter.
Recommended Process
At project kickoff, extract the critical general notes into a project data sheet: steel grade(s), weld code, bolt grade, coating system, inspection requirements. Distribute this sheet to the shop foreman, QC manager, purchasing agent, and coating supervisor.