Dear Linda, While CAR 3 and 4a do not specify any burn or flammability standards (for example, see CAR 3 below), it doesn't make sense to use upholstery materials that do not meet modern burn standards. The FAA specific standard is FAR 25.853 (a) & Appendix F Part I (a) (1) (ii) however, it makes further sense to upgrade that to the even more stringent Federal Standard 191 A-5903.1 (CID-A-A-2950A - which supersedes CCC-A-680a). This Federal Standard must be met by any fabric/foam/thread/rug manufacturer that desires to sell product to the Federal Government, hence, there are very few vendors that don't strive to meet these product standards. A popular website for purchasing fabrics is http://www.designerhomefabrics.com/ - they carry 5,641 different materials. Each fabric lists the burn standards that it meets. Whichever fabric you end up with, make sure to demand copies of the applicable burn certifications.
There is still some confusion on the part of your FSDO office, A&P and A&P IA on this subject. I recently attended the annual all day FSDO A&P IA refresher course and this was the first topic covered. The basic scenario presented to the A&P IAs in attendance by the FAA was "You are performing an Annual and you check out the interior on a CAR 3 or 4a airplane only to discover a newly upholstered interior (any or all seats, side panels, rugs, ceiling). You request the burn certs for each material as they are obviously not the original materials installed when the plane was built. The plane owner is unable to produce them. Do you sign off the airplane Annual placing the airworthiness liability squarely on your shoulders?" The final answer was left up to each A&P IA. Refurbishing these interior materials is an allowable log book activity for the airplane's owner just like changing the engine oil and filter. Due to the ambiguities of interpretation, I make certain that I have all the burn certificates for each material in the aircraft records, just as if the airplane was type certificated under FAR 23 rather than CAR 3 or 4a. As far as requiring a "No Smoking" sign to meet CAR 3 requirements, please also consider that directly over your knees is a gasoline tank - ON YOUR SIDE of the firewall !!! Yours, Chris Koch Buffalo, NY *CAR 3 Personnel and Cargo Accommodations* § 3.389 *Doors.* Closed cabins on all airplanes carrying passengers shall be provided with at least one adequate and easily accessible external door. No passenger door shall be so located with respect to the propeller discs as to endanger persons using the door. § 3.390 *Seats and berths**—(a) Passenger seats and berths.* All seats and berths and supporting structure shall be designed for a passenger weight of 170 pounds (190 pounds with parachute for the acrobatic and utility categories) and the maximum load factors corresponding to all specified flight and ground load conditions including the emergency conditions of § 3.386. (b) *Pilot seats.* Pilot seats shall be designed for the reactions resulting from the application of the pilot forces to the primary flight controls as specified in § 3.231. (c) *Categories U and A.* All seats designed to be occupied in the U and A categories under § 3.74 (c) (4) shall be designed to accommodate passengers wearing parachutes. § 3.391 *Safety belt or harness provisions.* Provisions shall be made at all seats and berths for the installation of belts or harness of sufficient strength to comply with the emergency conditions of § 3.386. § 3.392 *Cargo compartments.* Each cargo compartment shall be designed for the placarded maximum weight of contents and critical load distributions at the appropriate maximum load factors corresponding to all specified flight and ground load conditions. Suitable provisions shall be made to prevent the contents of cargo compartments form becoming a hazard by shifting. Such provisions shall be adequate to protect the passengers from injury by the contents of any cargo compartment when the ultimate forward acting accelerating force is 4.5g. § 3.393 *Ventilation.* All passenger and crew compartments shall be suitably ventilated. Carbon monoxide concentration shall not exceed 1 part in 20,000 parts of air. You can download the Federal Standard 191A from here: http://www.everyspec.com/FED-STD/ - it even specifies how the testing is performed.
