Is there a minimum level of impairment, and what if I have more than one impairment?

Paralympics Australia's classification FAQs say each sport has Minimum Impairment Criteria (wheelchair basketball and wheelchair rugby are given as examples). If you do not meet the criteria, you receive a Not Eligible – Minimum Impairment Criteria status, which does not dispute that you have an impairment. You can request classification by a different panel.

If you have multiple impairments, each is assessed separately and they are not combined. You may receive more than one class and must choose which to compete in, subject to sport rules.

Athletes in the same class can differ widely, because impairments vary and it is not feasible to have unlimited classes. The FAQs say differences in appearance or performance do not mean a classification is wrong or that someone is cheating.

Source: https://www.paralympic.org.au/classification/classification-faqs/