Always check your withholding with this tool if there are personal or financial changes in your life that might change your tax liability, for example new employment or a promotion changing income amount, or new family members altering the number of dependents you claim.
believe the answer you're looking for has to do with the pressure-altitude-voltage derating related to corona discharge, which increases (gets worse) with higher altitude and peaks at around 80-100,000' Typically this is considered to occur at votlages above 300 V peak, but be sure you are accounting for all transients and internal voltages.
Inhalation of air containing elevated levels of methylamine can result in a number of adverse health effects such as breathing difficulties, burning sensation, sore throat, headache and accumulation of fluid in the lungs (pulmonary oedema).