“The effective operation of a production facility for ventilators is only possible in an integrated supply chain with sub-suppliers of components,” wrote Kamann. “To meet the technological and quality requirements, close integration and exchange are necessary. New production lines would only generate additional output if the supply industry were also doubled, which is impossible in the short term from the perspective of regulatory qualification.”
Basically there are no parts to scale up the ventilators in the short term, so if they make any ventilators it just means firms that do it for years will make less.
mashable.com/article/experts-doubt-tesla-elon-musk-manufacture-ventilators/?europe=true
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