Interestingly Siemens and Eaton both manufacture a 'GFPE' breaker that has a 30ma/2000ms trip level, per some obscure super outdated UL standard. They can be identified by their 'red' test buttons.
If UL or CSA updated the standard for breakers to the more modern IEC standards for RCD 30ma/25ms they might be a good option for 2-prong NEMA 1- and 2- ungrounded receptacles and 240V equipment. But for now in the US the only RCD is a 5ma/25/ms UL Class A GFCI, which seems to nuisance trip due to the low 5ma trip level for wet locations.
However since per the NEC article 110.7, no proper functioning circuit should have "short circuits, ground faults, or any connections to ground other than as required or permitted elsewhere in this Code." thus not more the 30ma flowing on the Equipment ground (Earth Leakage) I am not sure why this GFPE breaker has not replaced the standard breaker (non GFCI ) where a standard breaker is permitted. At least in dry locations or fixed equipment in dwelling units.
