Workshop pinpoints top 2 factors behind BC escalator incidents
Technical Safety BC and Baker Engineering and Risk Consultants recently conducted a fault tree workshop to identify potential causes of escalator incidents.
Fault tree analysis uses a top-down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events. The workshop took a look at three common causes of escalator issues we have reported to us: escalator brake failure, escalator pile up, and escalator entrapment (i.e, shoes, scarves and other materials becoming entrapped in the escalator).
There were two causal factors during the sessions.
- Original equipment manufacturer (OEM) data for escalators is not shared with third party maintenance contractors, including data that could be considered safety critical. This was frequently cited as a potential source of hazard, as maintenance is not exclusively done by equipment manufacturers.
- Misuse of the escalator systems, either by operators, third party maintenance groups, or by the public was repeatedly cited as a causal factor in many areas. There is a strong belief that a lack of knowledge on the part of both the public and the escalator owners/operators contributes to the risks in operating this equipment.
At the end of the workshop, 13 recommendations were made to address the factors identified in the fault tree. Implementation of daily start-up inspections and yearly brake servicing for all escalators in BC was a key recommendation. This change was made in July (see safety order). There is data from Ontario’s Technical Safety and Standards Authority (TSSA) that indicates this will reduce the level of incidents related to mechanical failures within the province. Another recommendation was for Technical, Safety BC to explore a public safety campaign around misuse of escalators, which we are exploring.
One item of note was a recommendation for Technical Safety BC to review the maintenance, servicing, and repair components of the existing apprenticeship syllabus/exams and Skills Passport for escalators and ensure that it adequately supports these areas. The opinion of the workshop participants was that our current syllabus is strong on installation, but has areas for improvement around maintenance and repair.
The information from this fault tree study will help inform Technical Safety BC activities over the upcoming year, as pertains to improving safety of escalators and reducing the number of incidents.