Talk:ST elevation

Low quality...
(...) is at least 0.9 mV (usually representing 1 mm or 1 small square) in a limb lead or 0.29 mV (2 mm or 2 small squares) (...)

If 0.9 (0.90) mV represents about 1mm, the 0.29mV is represented by 2mm??? ST elevation is measured 0.24s (240ms) after J point? Not 0.08s (80ms)? Any citation?