Stair step geometry compliance with standard specifications for safety and usability: a study of selected university buildings in Ghana

Abstract

PurposeCompliance with standard specifications in stairway design and construction, particularly the step geometry, is imperative for the safety and usability of stairs. The purpose of this study, was to assess the compliance of stair step geometry parameters with standard specifications in selected public buildings in Ghana. Specifically, the study investigated the prevalence of deviations in step geometry parameters from standard provisions; how significant these deviations are in comparison, and by theoretical association, the potential risk of accidents.Design/methodology/approachField measurement of the geometric parameters of a total of 1954 steps in 204 flights of stairs within 28 university buildings was undertaken using a calibrated Multi Digit Pro + digital spirit level and a tape measure following the Nose-to-Nose Method. The results were analyzed using in Microsoft Excel 2016 and Minitab 18 and interpreted based on mean values, one-sample t-test and percentages.FindingsAlthough some parameters generally complied with standard specifications, dimensional inconsistencies in risers and treads of adjacent steps were most prevalent, and significantly at margins far above standard specifications. The findings of the study show the unique limitation of the step geometry design requirements specified in the current Ghana National Building Code and the National Building Regulation, and by association, the potential risk of accidents and discomfort in the use of stairs in public buildings such as those on university campuses.Practical implicationsThe observed deviations in the dimensions of risers and treads point to a lack of strict compliance with standard specifications in the design and construction of stairs. Apart from engaging skilled artisans, and intensifying supervision in stair construction, development control authorities in Ghana need to strengthen inspection of stairs during construction to ensure and enforce compliance.Originality/valueFindings of the study provide insight into stairway design, as well as stair safety and usability in a developing world context, and allows for a more comprehensive study of stair-related accidents and discomfort associated with stairs in public buildings as a basis for the review of standards and codes in Ghana and other developing countries.