A health care provider may only issue a certification that someone cannot wear respiratory protection to persons who are prevented from wearing it for serious medical reasons
According to point I/4 (only in Czech), the Ministry of Health of the Czech Republic orders:
All health service providers are hereby ordered to issue the certificates referred to in point 2. lett hh) of this Schedule with effect from 00:00 on 1 November 2021 until the revocation of this emergency measure. (hh) only to persons who are prevented from using respiratory protective equipment under this measure by serious health reasons, and are further directed to make a record of that fact and the reasons for it, including the diagnosis, in the person's medical record, including that the individual has been advised of the risks associated with not using respiratory protective equipment under this measure.
Text of point I/2 hh) only in Czech:
Persons who cannot, for serious medical reasons, wear a respirator or a medical face mask or similar device meeting at least all the technical conditions and requirements (for the product) of ČSN EN 14683+AC to prevent the spread of droplets and are able to prove this by medical certification; however, such persons shall be required to wear other respiratory protective equipment in accordance with this measure which is specified in the medical certificate, except where the medical certificate specifically states that the person cannot wear any respiratory protective equipment.
The full wording of the measure (only in Czech).