FAR 23.851 Fire extinguishers.
(a) There must be at least one hand fire extinguisher for use in the pilot compartment that is located within easy access of the pilot while seated.
SFAR No. 23
1. Applicability. An applicant is entitled to a type certificate in the normal category for a reciprocating or turbopropeller multiengine powered small airplane
that is to be certificated to carry more than 10 occupants and that is intended for use in operations under Part 135 of the Federal Aviation Regulations if he shows compliance with the applicable requirements of Part 23 of the Federal Aviation Regulations, as supplemented or modified by the additional airworthiness requirements of this regulation.
I think Part 23 may be for Part 135 operators.
Chuck (or others), is that right?