Ramadan Concrete Pour and a Heat Stroke Case
A infrastructure project in Kuantan is pouring bridge-deck concrete during Ramadan. Thirty workers, including eight new hires from outside the state, work 10-hour shifts from 7 a.m. to 6 p.m. with a 45-minute break. Measured WBGT at 2 p.m. is 33.5°C in direct sun; relative humidity is 75%. Workers wear long-sleeve coveralls and hard hats. Drinking water is available at the site office 300 m away; there is no shaded rest area near the deck. Two workers were treated for cramps last week and one was hospitalised with confusion, a temperature of 40.1°C and dark urine; the clinic diagnosed heat stroke and acute kidney injury. The project manager says 'Malaysians are used to the heat' and wants to continue to meet the deadline.
1. Assess the heat stress risk. Was the hospitalised worker's illness work-related? Explain.
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Risk assessment. WBGT 33.5°C in direct sun with 75% humidity, heavy concrete work, long-sleeve coveralls and a 10-hour shift place the crew in a high-risk heat category. The 45-minute break is inadequate, water is 300 m away, and there is no shaded rest area. The new hires are not acclimatised, and Ramadan adds dehydration risk.
Was the case work-related? The clinical picture - confusion, 40.1°C, dark urine and acute kidney injury - is consistent with heat stroke. The timing, outdoor work and lack of acclimatisation make occupational heat exposure the most likely cause. Other causes such as sepsis, dengue or malaria should be excluded clinically, but that does not remove the occupational link. Heat stroke is a medical emergency and a reportable occupational injury; the acute kidney injury is a serious complication.
Implication. This is not a single unusual case. The two cramp cases the week before are sentinel events showing the controls were already failing. The manager's statement that Malaysians are used to the heat is not a risk control; acclimatisation is task- and individual-specific.
2. Set out a work–rest and acclimatisation schedule, and the legal basis.
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Acclimatisation. New and returning workers should start at about 20% of the heat task on day 1, 40% on day 2, 60% on day 3, 80% on day 4 and 100% by day 5, with supervision. Workers on Ramadan should be reassessed and given lighter tasks or adjusted hours where needed.
Work–rest. Move heavy pours to early morning and late afternoon; provide shaded rest with fans or misting near the deck; use work–rest cycles such as 45 minutes work and 15 minutes rest in the hottest period, or more rest if WBGT rises. Provide cool water within reach and encourage about 250 mL every 20 minutes; include electrolytes for long shifts. Use a buddy system and urine colour checks.
Legal basis. OSHA 1994 s.15 requires a safe system of work; the employer must assess heat risk and control it so far as is practicable. The DOSH heat stress guidance is the practical benchmark. Record the risk assessment, the schedule and the controls. PPE should be breathable; cooling vests may help but are not a substitute for rest and shade.
3. What medical surveillance and return-to-work conditions would you require?
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Medical surveillance. Pre-placement assessment for heat-exposed workers: blood pressure, BMI, renal function, urine analysis and history of heat illness, kidney disease, diabetes and medication. Annual review during hot work. Any worker with cramps, dizziness or dark urine should be assessed and removed from heat until recovered.
Return to work after heat stroke. The worker needs physician clearance, including renal function review. Heat stroke can leave increased heat intolerance and kidney risk. I would require a gradual return, no heat exposure for at least 7–14 days depending on medical advice, no lone work, hydration monitoring and a review before full duties. Document the restrictions and communicate only what is necessary to the supervisor.
Programme review. After the case, audit water access, shade, rest breaks, acclimatisation records and supervisor training. Report the case and corrective actions to the safety and health committee and to DOSH as required. Track heat-related symptoms weekly through the peak period.