13 LOAD LIFTING ANALYSIS

Ergoniza Intelligent includes a specific mode for analyzing tasks in which a worker manually raises or lowers a load between an origin and a destination. The analysis considers lifting geometry and exposure conditions through an implementation of the Revised NIOSH Lifting Equation.

Load Lifting mode can be activated with the corresponding button at the top center of the interface (Figure 1). Unlike single- or multiple-posture analysis, the lifting module does not use an isolated body posture or a generic temporal sequence as its main unit of analysis. Instead, it analyzes a lifting activity that may comprise several tasks.

The assessment has two distinct dimensions. A lifting task represents specific handling conditions: weight, frequency, coupling, handling method, and origin and destination geometry. A lifting period represents the interval during which the task profile is performed before recovery.

An assessment can contain one or more tasks and, independently, one or more periods. All periods currently use a shared profile: the same tasks are performed at the same frequencies in every period. Periods are not additional NIOSH tasks; they describe when that profile is performed.

Temporal organization can be defined as one lifting period, a regular pattern of periods, or a custom sequence. The entered durations and recovery times determine the evaluation blocks and the duration category applicable to the frequency multiplier.

In the Load Lifting mode interface, users can define general analysis parameters, create one or more lifting tasks, adjust the specific conditions of each task, and view the resulting overall and partial results, as shown in Figure 65. Origin and destination results are displayed separately because conditions may differ at the two points of the movement.

In a single-task analysis, each block is assessed using the task's Lifting Index. In a multitask analysis, each block is assessed using the Composite Lifting Index for the task set. All blocks are calculated and compared. The block producing the least favorable index is identified as the governing block and establishes the representative overall assessment result. Results for the other blocks are retained for review but are neither added nor averaged.