Job enlargement and mechanical exposure variability in cyclic assembly work.

Cyclic assembly work is known to imply a high risk for musculoskeletal disorders. To have operators rotate between work tasks is believed to be one way of decreasing this risk, since it is expected to increase variation in mechanical and psychological exposures (physical and mental loads). This assumption was investigated by assessing mechanical exposure variability in three assembly tasks in an electronics assembly plant, each on a separate workstation, as well as in a 'job enlargement' scenario combining all three stations.

A method to determine joint moments and force distributions in the shoulders during ceiling work -- a study on house painters.

OBJECTIVE: The purpose of this study was to propose and apply a method to study the net load and the force distribution in the shoulder during sanding of a ceiling. DESIGN: Sanding of a ceiling was studied in an experimental set-up. BACKGROUND: Among painters there is a high frequency of neck and shoulder complaints and some particularly strenuous tasks are sanding and painting of ceilings with tools attached to extension handles.

Hand-arm symptoms related to impact and nonimpact hand-held power tools.

Hand and arm symptoms among workers using impact and non-impact hand-held power tools were investigated in a cross-sectional study and a 5-year follow-up study. The study population consisted of concrete workers (n = 103), truck assemblers (n = 234), electricians (n = 101), platers (n = 140) and lumberjacks (n = 102). Of the original 680 subjects, we followed up 312 after 5 years.

Acute effects of vibration from a chipping hammer and a grinder on the hand-arm system.

Objectives: The purpose of this study was to compare various effects on the hand-arm system of vibration exposure from a chipping hammer and a grinder with the same frequency weighted acceleration. Grip and push forces were measured and monitored during the exposure. The various effects were: muscle activity (measured with surface electrodes), discomfort ratings for different parts of the hand-arm system (made during and after exposure), and vibration perception threshold (for 10 minutes before and 10 minutes after the exposure).

Reaction forces, tool handle displacements and discomfort ratings during work with shut-off nutrunners.

Reaction forces, hand-arm displacement and subjective ratings were studied during securing of threaded fasteners with nine right-angle nutrunners. The nutrunners had three different preset spindle torques and three different shut-off mechanisms. The tools were tested according to the international ISO method and with a method proposed by the authors in a previous study.