Assertion: fuel cell's part | /r/HasProperty | acceptable
Facets:
value: usually
type: DEGREE
Source sentences:
text: The platinum catalyst on the membrane is easily poisoned by carbon monoxide (no more than one part per million is usually acceptable) and the membrane is sensitive to things like metal ions, which can be introduced by corrosion of metallic bipolar plates, metallic components in the fuel cell system or from contaminants in the fuel/oxidant.