Polarized System (dc) 2 : A system in which the grounded (negative) and ungrounded (positive) conductors are connected identically in relation to all terminals or leads on all devices in the circuit
NFPA 302 Fire Protection Standard for Pleasure and Commercial Motor Craft, 1998 ed. https://www.nfpa.org/assets/files/AboutTheCodes/30 2/302-A2003-rop.PDF, (Std: Fr Prac for Pleasure and Comm Motor Craft - Amer) {292 NFC}