Ergonomic Risk Assessment of Kitchen Workers: CMDQ and Manual Lifting Analysis

Aims: This study provides a comprehensive ergonomic assessment in a kitchen, combining subjective and objective measures.
Method and Materials: In this cross-sectional study, kitchen staffs completed the Farsi version of Cornell Musculoskeletal Discomfort Questionnaire (CMDQ). Hierarchical Task Analysis (HTA) broke down tasks to identify key physical demands. Manual handling tasks were evaluated using National Institute for Occupational Safety and Health (NIOSH), Washington Industrial Safety and Health Act (WISHA), Key Indicator Methods (KIM), and Manual Handling Assessment (MAC). Cohen’s Kappa (κ) assessed inter-method agreement.
Findings: The CMDQ revealed highest discomfort in the lower back region (11.33 ± 8.38) and right shoulder (11.00 ± 5.62). Objective tools identified several tasks as high risk: the Rice Cook's handling of 50kg rice containers (NIOSH Lifting Index (LI)=3.4; KIM Score=56, Risk Level 3) and 40kg rice strainers (NIOSH LI=5.48; KIM Score=132, Risk Level 4), and the Stew Cook's preparation of food in 30kg pans (NIOSH LI=3.56; KIM Score=41, Risk Level 2). Inter-method agreement (κ) was moderate to good between WISHA and NIOSH (κ=0.4942) and between MAC and KIM (κ=0.5170). NIOSH showed fair agreement with KIM (κ=0.2540) and slight agreement with MAC (κ=0.1960). WISHA’s agreement with MAC and KIM was very slight (κ=0.0837 and κ=0.1143 respectively).
Conclusion: kitchen tasks pose significant ergonomic risks, aligning with reported lumbar and shoulder discomfort. The varied agreement among MMH tools emphasizes the value of a multi-method approach for comprehensive risk assessment. Ergonomic interventions like load reduction and workstation adjustments are recommended.