Welcome to the 10th Edition Major Changes blog series! As part of Code Red Consultant’s 10th Anniversary celebration, we will be doing a 10-part series on major changes to the 10th edition of 780 CMR, Massachusetts State Building Code.
To kick things off, this post is one of several egress-related entries that highlights some changes associated with egress occupant loads, lighting requirements, and turnstiles.
The occupant load factor for business areas (i.e. offices) has been increased from 100 to 150 gross square feet per occupant. This change was initially implemented into the 2018 International Building Code (IBC) following numerous studies of current office space layouts and furnishings used within business occupancies. Notably, a study conducted by WPI undergraduate students in collaboration with the NFPA Fire Protection Research Foundation recommended increasing the business occupant load factor and was cited as contributing rationale for the change. This shift results in a decreased calculated occupant load for office spaces, aligning occupant load calculations with NFPA 101, Life Safety Code. For more concentrated business uses, like call centers or trading floors, a factor of 50 gross square feet per occupant (or higher) is permitted where approved by the building official.
Exit and exit access stairway lighting requirements have been increased from 1 foot-candle to 10 foot-candles at the walking surface when the stair is in use. This adjustment also aligns IBC requirements with those of NFPA 101. This change will improve safety within a building by enhancing visibility for occupants navigating stair treads and handrails. Note that stairways are not always required to be fully illuminated; illumination can be activated when the stair is in use through the use of a motion detector or similar device.
Another notable change coming to the 10th Edition pertains to security access turnstiles, often referred to as speed gates. Currently, in the 9th edition, individual turnstiles along the means of egress are always limited to an egress capacity of 50 occupants. The change, first introduced in the 2018 Edition of IBC, allows the egress capacity of a turnstile to be calculated based on its clear width, similar to a door or gate. (Turnstiles providing less than 32” of clear width will still be limited to 50 occupant capacity.) This approach for turnstiles is permitted where the building is fully sprinklered and the turnstile opens (fails safe) during each these conditions: loss of power, automatic fire alarm initiation (excluding manual pull stations), and activation of a manual release device located on the egress side of the gate or other approved location.
It’s important to highlight that the 10th edition of 780 CMR has not been finalized or adopted in Massachusetts and is potentially subject to further changes. Our current projection for the adoption of the 10th edition is Q2 of 2024 – see our prior post which outlines the overall process and timeline.
Stay connected for more Insights posts as we continue our “10th Edition Major Changes” series as part of CRC’s 10th Anniversary!