Filter Smoke Number → Black Carbon

Convert an FSN (Bosch) reading to mass-concentration black carbon in exhaust, per IMO's correlation function.

CombustionEmissionsBlack Carbon

Filter Smoke NumberFSN

Black carbon concentration: 7.70mg/m³

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

BC = \frac{1}{0.405} \cdot 5.32 \cdot FSN \cdot e^{0.318 \cdot FSN}

Symbol	Meaning	Unit
$FSN$	Filter smoke number (ISO 10054 / Bosch)
$BC$	Black carbon concentration	mg/m³ exhaust

Source: IMO MEPC BC correlation (ISO 8178 annex); Mollenhauer & Tschoeke - Handbook of Diesel Engines

In short

Convert an FSN (Bosch) reading to mass-concentration black carbon in exhaust, per IMO's correlation function.

Learn the theory Engine Performance Monitoring: PMI Systems