IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

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(June 12, 10AM) Gradual resumption of the Laboratory Division’s activities. Due to the rapid spread of COVID-19, and to ensure the health and safety of its employees and its entire network, the IRSST has implemented exceptional measures.

Stability Criteria for Ladders and Stepladders


Falls from heights are one of the main causes of accidents in Quebec and the second-most costly cause, amounting to an average of $397 million per year from 2010 to 2012. Statistics for injuries involving ladders or stepladders reveal an increase over the years.

A ladder’s stability is mainly affected by its angle of slope. Studies of the topic have concluded that the ideal angle of slope to avoid foot slippage or tipping backward is approximately 75°. In addition to the slope, the worker’s height and the task to be performed affect a ladder’s stability.

This study aims to determine the limits of stability during the use of portable ladders and stepladders according to these criteria.