Here's something from the SCTA/BNI:
Notice to racers that some HELMETS have expired
Helmets with a SNELL rating of SA2010, M2010 and helmet certified to FIA8860-2009 expired on January 1 , 2022. (Rule Book sections 3.A.2 and 7.C.1). Also E.C.E. 22.05 motorcycle helmets manufactured before 2011 have expired.
Given the current supply chain issue, we strongly recommend you check the date codes on your helmet and, if necessary, order a replacement early.
NOTE: Most new helmets are dimensionally larger to meet the higher protection requirements in the new standards. We advise you to check the fit of the new helmet inside the roll cage structure of your vehicle. Rule 3.B.1 requires "a front hoop of the roll cage shall be at least three (3) inches in front of the driver while the driver is in his normal driving position."
