Dynamic Amplification Factor (DAF) or Dynamic Increase Factor (DIF), is a dimensionless number which describes how many times the deflections or stresses should be multiplied to the deflections or stresses caused by the static loads when a dynamic load is applied on to a structure. When lifting an object during a sub-sea operation, the DAF is calculated based on dynamic hydraulic forces or on snap-forces.
D A F = F t o t a l M g {\displaystyle DAF={\frac {F_{total}}{Mg}}}
Where:
M {\displaystyle M} is the mass of the object in air (kg)
g {\displaystyle g} is the acceleration of gravity (9.81m/s2)
F t o t a l {\displaystyle F_{total}} is the largest of F s t a t i c − m a x + F h y d {\displaystyle {F_{static-max}+F_{hyd}}} or F s t a t i c − m a x + F s n a p {\displaystyle F_{static-max}+F_{snap}} (N)
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