CGA PS-31阐述了杂质对质子交换膜（PEM）设备的潜在负面影响，以及在制造和安装氢气供应系统期间，为管理可引入氢气供应系统的固体、液体和过渡杂质而可能采取的步骤。

CGA PS-31 addresses the potential negative impact of impurities on Proton Exchange Membrane (PEM) equipment and the steps that may be taken to manage the solid, liquid, and transitional impurities that can be introduced into a hydrogen supply system during the fabrication and installation of a hydrogen supply system.