Flicker Metrics for Common Sources
| Technology | Percent Flicker | Flicker Index |
|---|---|---|
| Incandescent lamp | 6.3 | 0.02 |
| T12 linear with magnetic ballast | 28.4 | 0.07 |
| Spiral compact fluorescent lamp (CFL) | 7.7 | 0.02 |
| Quad-tube CFL with magnetic balast | 37.0 | 0.11 |
| Quad-tube CFL with electronic balast | 1.8 | 0.00 |
| Metal halide lamp | 52.0 | 0.16 |
| High-pressure sodium lamp | 95.0 | 0.30 |
| Direct current LED | 2.8 | 0.0037 |
| LED with significant flicker | 99.0 | 0.45 |
Source: Michael Poplawski, Naomi Miller, PNNL (2011); Michael Grather, Luminaire Testing Laboratory (2009)