A review of machine-guarding recommendations

Area of Science:

• Industrial Safety
• Ergonomics
• Human Factors Engineering

Background:

• Machine-guarding standards were established in the 1940s based on limited anthropometric data.
• Subsequent comprehensive anthropometric surveys have not been used to validate these original recommendations.
• The changing demographics of the American workplace, including increased representation of women and minorities, necessitate updated safety standards.

Purpose of the Study:

• To assess the continued validity of 1940s machine-guarding recommendations against current anthropometric data.
• To identify necessary modifications to ensure safety for diverse populations, particularly women and minorities.
• To compare existing gap size and safe distance guidelines with contemporary human body measurements.

Main Methods:

• Data from six extensive anthropometric surveys were analyzed.
• Comparisons were made between existing machine-guarding drawings and current anthropometric data.
• Length dimensions were based on the 99th percentile male, and thickness dimensions on the 1st percentile female to minimize risk.

Main Results:

• Many of the original machine-guarding recommendations were found to be consistent with current anthropometric data.
• Several recommendations require modification to better reflect contemporary population measurements.
• Certain current dimensions lack correlation with incompressible joints and should be reconsidered.

Conclusions:

• Existing machine-guarding recommendations are largely valid but require updates for optimal safety.
• Proposed modifications aim to enhance protection for all workers, especially women and minorities.
• Eliminating dimensions not correlated with incompressible joints is recommended for improved industrial safety standards.