40 CFR Part 63, Table 24 — Typical Number of Columns as a Function of Tank Diameter for Internal Floating Roof Tanks With Column Supported Fixed Roofs a
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
| Tank diameter range (D in feet) | Typical number of columns, (NC) |
|---|---|
| 0 <D ≤85 | 1 |
| 85 <D ≤100 | 6 |
| 100 <D ≤120 | 7 |
| 120 <D ≤135 | 8 |
| 135 <D ≤150 | 9 |
| 150 <D ≤170 | 16 |
| 170 <D ≤190 | 19 |
| 190 <D ≤220 | 22 |
| 220 <D ≤235 | 31 |
| 235 <D ≤270 | 37 |
| 270 <D ≤275 | 43 |
| 275 <D ≤290 | 49 |
| 290 <D ≤330 | 61 |
| 330 <D ≤360 | 71 |
| 360 <D ≤400 | 81 |
a Data in this table should not supersede information on actual tanks.