SAFETY CONSIDERATIONS WHILE DESIGNING STAIRCASES
When building a stair, functionality is the most important consideration. Extreme accuracy must be used for a safe design. Aspects of total height and span should be looked into and tread widths and riser heights should be carefully calculated. After looking into Codes and By-Laws, materials for constructions should also be considered carefully as they determine the final detailing, types of construction and safety additions.
Stairs that are too steep, have changes in direction (winders) or are tightly spiraled are more difficult to use safely. Spiral or curved stairs must meet specific design requirements so that the curve is not too tight. Because of the increased risk of slips and trips on spiral and helix stairs, these designs should be avoided unless space constraints dictate that there is no alternative. Helical and spiral stairs should
not be used for means of escape in buildings where a high percentage of children or disabled people are
likely to be in the building at any one time.
General safety considerations while designing staircases for public and private use include the following; to prevent tripping, make sure all risers and treads are uniform throughout a flight, keeping variations in riser height and tread width in a flight of stairs to less than 3/16 inch. Using round nosings and enhancing stairs visually to make edges more distinct will also help to prevent missteps. Treads narrower than 9 inches in width result in the greatest number of tripping accidents. Research indicates that tread widths of 10 to 13 inches and riser heights of 6 to 8 inches are the most foot-friendly. Treads should project past the riser by at least 3/5 inches, but not more than 1 inch to prevent toes being caught while walking up stairs.
Risers should be even – the riser height plus one tread depth should be in the 25 inches to 26 inches range. A tread depth should be of at least 11 inches. Stair width should be...