What is California Technical Bulletin 133 and how does it apply to furniture?

According to BIFMA, TB-133 was repealed in January 2019. 

Richardson Seating is committed to assisting its customers with meeting specific fire code standards, including the CAL 133 standard if so desired. We are here to work with you from design and material selection through the rigorous testing process to make sure the custom furniture you order from us does meet all necessary regulations.  This standard has been used in California and Boston.  Many places go back and forth because in order to make materials fire resistant, you need chemicals.  The chemicals may be considered hazardous so states want to ban them.  Many states are more concerned about chemicals than they are of fire.

What is the CAL TB 133 Fire Code?

The CAL TB 133 (California  Technical Bulletin 133)  standard is one of the strictest fire code standards in the US, developed in California but adopted by other states and municipalities. The CAL 133 standard is developed for upholstered furniture and applies to public buildings or "public occupancy areas," which are identified as an area containing ten or more articles of seating furniture. CAL 133 has standards for heat production, mass loss, smoke opacity, and carbon monoxide production. CAL TB 133 does not apply to residential furniture. Furniture that meets the CAL TB 133 Standard will also meet the Boston Fire Code standard.

How is furniture tested?

For both the Boston and CAL TB 133 Fire Code, a full scale piece of furniture is placed in a specially designed room where the furniture or mockup is exposed to an approximate 16 KW open flame for eighty seconds. The temperatures at the 4 foot level and ceiling, the mass loss of the furniture, and the carbon monoxide levels in the room are monitored constantly. Also monitored constantly are oxygen consumed, peak heat release, and total heat release.              


A chair undergoing CAL 133 Testing

Chair getting tested for Cal 133

Helpful links below:


State of California Technical Bulletin 133

Additional Information on Flammability Testing

Explanation on CAL 133 Testing from a Testing Laboratory

Leave a comment

Please note, comments must be approved before they are published