Synthetical lethal pairs is equivalent to parallel components

The network survivor function S(t) is based on network structure function (see Leemis09, example 3.9 figure 3.9 on page72). Mortality rate (hazard rate) can be found by definition:  h(t) = -S' / dS .

$S_a$ and $S_b$ follow the Weibull model in earlier aging based on GG01.