What is the criteria for the max slope of a ramp serving egress?

The maximum slope of a ramp serving egress is set at a ratio of 1:12. This means for every inch of vertical rise, there should be at least 12 inches of ramp run. This criteria is established to ensure accessibility and safety, particularly for individuals with disabilities. A 1:12 slope is generally considered the steepest angle that allows for safe and manageable navigation for wheelchair users and others who may require assistance.

Choosing a steeper slope, such as 1:10, can cause difficulties for users in maintaining balance and control while descending, and can increase the effort needed to ascend the ramp, potentially leading to safety hazards. Conversely, a gentler slope such as 1:16 or 1:20 would be easier to navigate but may not be necessary for egress ramps, which must adhere to the established guidelines to ensure they are effective in emergency situations. Therefore, the 1:12 slope is the standard accepted norm for balancing safety and accessibility in building design.