40 CFR §1068.430

1. (a)We may suspend your certificate of conformity for a family if it fails the SEA under § 1068.420. The suspension may apply to all facilities producing engines/equipment from a family even if you find noncompliant engines/equipment only at one facility.
2. (b)We will tell you in writing if we suspend your certificate in whole or in part. We will not suspend a certificate until at least 15 days after the family fails the SEA. The suspension is effective when you receive our notice.
3. (c)You may ask for a hearing as described in subpart G of this part up to 15 days after we suspend the certificate for a family. If we agree that we used erroneous information in deciding to suspend the certificate before a hearing is held, we will reinstate the certificate.