Across Europe, lift capacity signs for the maximum number of passengers permitted based on weight are out of date with current obesity trends, finds new research being presented at this year's European Congress on Obesity (ECO) in Istanbul, Turkey (12-15 May). Additionally, new recommendations to reflect lift passenger space requirements are not evidence based and should be linked secular trends in obesity or body shape.
As author Nick Finer, President of the International Prader Willi Syndrome Organisation and past Clinical Professor of Medicine at UCL, London, UK explains, "The failure of lift manufacturers to adapt to rising levels of obesity and body size means that lift capacities are overestimated meaning that journey times are likely to be increased and that safety could be compromised. What's more, suggesting more people can fit in a lift than is comfortable is stigmatising people living with obesity."
Modernising these signs and systems is crucial for maintaining safety, enhancing performance, and increasing accessibility, says Finer: "Recent recommendations to size lifts to fit modern users based on two-dimensional (2D), or floor space area should give passengers more personal space and comfort, but they are not linked to secular trends in obesity or size/body shape, and an urgent rethink is needed."
The scale of the obesity challenge facing the UK and Europe is substantial, with one in four adults in England estimated to be living with obesity in 2023 to 2024 [1]. Rising levels of obesity not only have serious health implications, but also has consequences for the manufacturing industry. Whether the lift industry is responding to these secular trends remains poorly understood.
To find out more, Finer set out to investigate whether lift design has kept pace with the increasing prevalence and severity of obesity over the past five decades (1972-2022).
Lift manufacturers are required to display maximum weight allowance and passenger capacities (i.e., the maximum number of passengers the lift can accommodate). Industry standards define the passenger capacity by dividing the maximum load of a lift by the average weight of a passenger. Historically, European standards, such as EN81-20 and the Lifts Directive (2014/33/EU), assumed an average weight of 75kg per person [2].
In the UK, the average weight of men in the mid-1970s was 75 kg, while the average weight of women was 65 kg. Today, this is approximately 86 kg and 73 kg, respectively [3].
Between 2000 and 2024, Finer gathered a convenience sample of data from 112 lifts across Western Europe (the UK, France, Germany, Spain, Italy, Austria, Finland) which had been manufactured by 21 companies between 1970 and 2024. For each lift, information on the year of manufacture, maximum weight allowance and maximum number of passengers was obtained from the displayed safety signs.
Average weight allowance per person (calculated by dividing maximum weight allowance by maximum number of passengers) for the year of manufacture was compared to average adult weight for that year obtained from the UK National Health Survey (1994 to 2022). Duplicate data (i.e., similar average weight) for any year of manufacture were excluded.
The analysis found that average lift passenger weight allowance increased significantly between 1972 and 2002 (with a wide range from 55 kg to 91.7 kg), and was strongly correlated with the increasing average population weight, suggesting that manufacturers at that time were responsive to the growing prevalence of obesity. For example, in the 1990's individual lift weight allowances increased to around 80 kg against population averages of 76 kg (see figure in full abstract).
After 2002, however, there was no significant increase in the assumed average weight of lift users, so despite an average population weight of 79 kg, the assumed average weight remained at 75kg. This likely reflects lift manufacturers switching their calculations of lift capacities to assumed floor space requirements based on a standard 2D elliptical shape or ellipse of 0.21m2.
However, Finer notes that, "The switch from weight to floor space area has not kept pace with secular trends in obesity or body shape, even though excellent data on the increase in average waist circumference, and thus 2D shape size, exist."The author acknowledges several limitations to the study, including the small sample size and its descriptive nature, which precludes causal inference and warrants confirmation in larger studies.
