Workload of window cleaners using ladders differing in rung separation

Institute for Fundamental and Clinical Human Movement Sciences, Faculty of Human Movement Sciences, Vrije Universiteit, Van der Boechorststraat 9, 1081 BT Amsterdam, The Netherlands.
Applied Ergonomics (Impact Factor: 2.02). 06/2005; 36(3):275-82. DOI: 10.1016/j.apergo.2005.01.013
Source: PubMed


The objective of the present study was to compare energetic workload, perceived exertion, perceived discomfort, safety, and mechanical load at lower limb joints among window cleaners during usage of extension ladders with 30 and 35 cm rung separation. Eleven healthy male professional window cleaners of short and tall stature participated in this study. No significant differences between 30 and 35 cm rung separation were observed for the energetic workload. Results concerning the perceived exertion, discomfort, and safety indicate that 35 cm rung separation is preferred. Based on the mechanical load at the hip, knee, and ankle during ascending and descending the ladder, 30 cm rung separation is preferable to 35 cm rung separation. It is advised to climb ladders with the knees inside the side rails of the ladder, but this seems only possible with 35 cm rung separation. Findings of the presents study suggest that overall, a 35 cm rung separation is marginally favourable while using extension ladders.

Download full-text


Available from: Jaap Van Dieen,
91 Reads
  • Source
    • "Again, we did not measure kinematics during climbing . However, within the constraints of typical ladder climbing, the total moment at the hip is similar to the moments observed in running (Hoozemans et al., 2005). Although ladders are only a modern method of climbing, the experimental simplicity facilitated our experiment. "
    [Show abstract] [Hide abstract]
    ABSTRACT: It has been suggested that the uniquely large gluteus maximus (GMAX) muscles were an important adaptation during hominin evolution based on numerous anatomical differences between humans and extant apes. GMAX electromyographic (EMG) signals have been quantified for numerous individual movements, but not across the range of locomotor gaits and speeds for the same subjects. Thus, comparing relative EMG amplitudes between these activities has not been possible. We assessed the EMG activity of the gluteal muscles during walking, running, sprinting, and climbing. To gain further insight into the function of the gluteal muscles during locomotion, we measured muscle activity during walking and running with external devices that increased or decreased the need to control either forward or backward trunk pitch. We hypothesized that 1) GMAX EMG activity would be greatest during sprinting and climbing and 2) GMAX EMG activity would be modulated in response to altered forward trunk pitch demands during running. We found that GMAX activity in running was greater than walking and similar to climbing. However, the activity during sprinting was much greater than during running. Further, only the inferior portion of the GMAX had a significant change with altered trunk pitch demands, suggesting that the hip extensors have a limited contribution to the control of trunk pitch movements during running. Overall, our data suggest that the large size of the GMAX reflects its multifaceted role during rapid and powerful movements rather than as a specific adaptation for a single submaximal task such as endurance running. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.
    American Journal of Physical Anthropology 01/2014; 153(1). DOI:10.1002/ajpa.22419 · 2.38 Impact Factor
  • Source
    • "Some falls from equipment occur as mine workers enter and exit equipment via the ladder or stair systems. Fairly extensive research has already been conducted regarding ladder and stair climbing (Bjornstig & Johnsson, 1992; Bloswick, 1999; Bloswick & Chaffin, 1990; Bloswick & Crookston, 1992; Chang, Chang, & Matz, 2005; Chang, Chang, Matz, & Son, 2004; Dewar, 1977; Fathallah & Cotnam, 1998, 2000; Giguere & Marchand, 2005; Hakkinen, Pesonen, & Rajamaki, 1988; Hammer & Schmalz, 1992; Hoozemans et al., 2005; Kowalk, Duncan, & Vaughan, 1996; McIntyre, 1983; Partridge, Virk, & Antosia, 1998; Patenaude, Marchand, Samperi, & Belanger, 2001; Shepherd, Kahler, & Cross, 2006; Yang & Ashton-Miller, 2005). Much of this research focused on impact forces during various descent techniques, friction requirements, or the effect of physical changes to ladders (e.g., ladder slant, rung separation). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The objective of this study was to evaluate the circumstances leading to fall from equipment injuries in the mining industry. The 2006 and 2007 Mine Safety and Health Administration annual injury databases were utilized for this study whereby the injury narrative, nature of injury, body part injured, mine type, age at injury, and days lost were evaluated for each injury. The majority of injuries occurred at surface mining facilities (approximately 60%) with fractures and sprains/strains being the most common injuries occurring to the major joints of the body. Nearly 50% of injuries occurred during ingress/egress, predominantely during egress, and approximately 25% of injuries occurred during maintenance tasks. The majority of injuries occurred in relation to large trucks, wheel loaders, dozers, and conveyors/belts. The severity of injury was independent of age and the median days lost was seven days; however, there was a large range in severity. From the data obtained in this study, several different research areas have been identified for future work, which include balance and stability control when descending ladders and equipment design for maintenance tasks.
    Journal of safety research 12/2009; 40(6):455-60. DOI:10.1016/j.jsr.2009.10.002 · 1.34 Impact Factor
  • Source

Show more