Seakeeping - MSW / MSH Comfort Criterion

Motion sickness incidence from ISO 2631-1 / NORDFORSK - integrated weighted acceleration exposure over 2 hours.

SeakeepingComfortMSW

σ vertical accelm/s²Encounter freqHz

Weighted accel: 1.48m/s²

MSI (2 h exposure): 89%

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

\text{MSI} = f(a_w, t) \approx a_w \cdot t_{min}

Symbol	Meaning	Unit
$\sigma_z$	σ vertical acceleration	m/s²
$a_w$	Frequency-weighted acceleration	m/s²

Source: ISO 2631-1:1997

In short

Motion sickness incidence from ISO 2631-1 / NORDFORSK - integrated weighted acceleration exposure over 2 hours.

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