Abstract

Part of the authors’ professional duties is the regular condition and compliance auditing of 2,600 lifts across 20 diverse client portfolios throughout the UK. Any fault or non-compliance found that represents a hazard to users or engineers is reported back to the client and service provider alike via a Hazard and Incident (H&I) Report.

During 2023 the authors raised 574 H&I Reports, suggesting that at any one time, around 20% of this portfolio demonstrated a safety or compliance issue.

Of those 574 H&I Reports, a startling 481 (84%) related directly to the failures of batteries that support emergency systems like autodiallers, lighting and passenger release systems. As an example, 262 lifts (10% of the portfolio audited) presented with non-operational autodiallers when the lift was isolated, that were operational with mains power on.

This data leads to the alarming hypothesis that 18.5% of this portfolio’s emergency batteries will be ineffective at any given time, and 10% of autodiallers will be entirely inoperative during a mains power failure.

It is important to recognise that the duty holders responsible for this portfolio have the means to fund annual audits and maintenance provision, which cannot be said for 100% of operational lifts in the UK. Thus the 18.5% of this portfolio presenting with battery failures is likely to be an underestimate of the national picture, raising the frightening prospect of large numbers of lift users potentially being trapped in the dark with no means of communication.

This paper conducts a detailed analysis of the dataset, identifying the functions affected by battery failures, commenting on the potential impact to users, and explores component and system designs that both aid and hinder effective charging, monitoring and replacement of battery systems.

The authors see this issue as a significant safety failing in the UK’s (and potentially the global) vertical transportation industry. We are not content with merely highlighting this issue and will be championing an industry-wide campaign to address these safety-critical failings.