California Technical Bulletin (TB 133)

TB 133 originated in California, but other states have begun to adopt its strict guidelines aimed at promoting public safety.

  • TB 133 is a flammability test for upholstered seating for use in spaces/ buildings considered to be in public, including healthcare facilities, daycare centers, restaurants, hotels and penal institutions.
  • Special materials, including barrier wrap and/or CMHR foam, are used to comply with TB 133. Martin Brattrud must be consulted to obtain pre-approval for fabric and leather to be used on orders requiring TB 133 compliance.
  • The up-charge for TB 133 construction is 20% for each chair or sofa. Purchase orders requesting TB 133 certification will require a full-scale burn test of a finished furniture piece identical to the unit to be installed on the job site.
  • The fabric to be tested must be supplied by the client. The charge for certification is $875 NET test/per item, which includes manufacturing and testing of the sample to be ignited.
  • Laboratory testing adds 3-4 weeks to Martin Brattrud standard lead times. Purchase orders will not be placed in production until mock-up has passed TB 133.
  • Barrier wraps, flameproofing and/or CMHR foam affect the hand, sit and look of most styles. The special materials used to obtain TP 133 compliance or certification will yield a firmer seat and less supple hand.
  • Purchase orders must clearly stipulate the need for TB 133 compliance or certification. It is the specifier’s responsibility to check with local agencies for flammability and other code requirements.
  • Martin Brattrud can supply Combustion Modified High Resiliency (CMHR) foam for select styles. Please contact the factory for pricing.