Evaluating the Effectiveness of Designed Safety Signage in Manufacturing Facilities in Kaduna State

Workplace safety in manufacturing facilities across Kaduna State, North West Nigeria, is compromised by inadequate, non-standardised, and poorly designed safety signage that fails to communicate hazard information effectively to a workforce characterised by variable literacy levels and diverse linguistic backgrounds. This study evaluates the effectiveness of existing safety signage in fifteen manufacturing facilities across the Kaduna and Kakuri industrial layouts, applying visual communication evaluation frameworks and occupational safety standards. Data collection involves sign legibility testing at operational distances, comprehension surveys administered to four hundred and eighty production workers in English, Hausa, and pictogram-only formats, and analysis of workplace incident reports over a two-year period. Findings reveal that sixty-seven percent of surveyed workers cannot correctly interpret standard ISO safety pictograms without accompanying text, and that facilities with higher incidences of pictogram misinterpretation recorded significantly more minor injury incidents during the study period. The study develops a Signage Effectiveness Assessment Tool for use by safety officers and redesigns eleven of the most misinterpreted signage types using locally validated pictograms, colour coding, and bilingual labelling in English and Hausa. Redesigned prototype signage is installed in three pilot facilities and evaluated through repeat comprehension surveys. Comprehension rates for critical hazard signs improve by an average of fifty-three percent in pilot facilities. Recommendations include mandatory signage effectiveness auditing by the Factory Inspectorate Division of the Kaduna State Ministry of Labour and Employment. Keywords: safety signage, manufacturing, visual communication, Kaduna State, workplace safety.