Around 12h on 15/1, two male workers opened a manhole at the entrance of Ngoc Ha market to inspect the drainage system. One worker descended into the manhole using a ladder and was suddenly overcome by gas, crying out for help.

The manhole where the two workers suffered the accident. *Minh Bang*

Upon seeing his colleague in distress, the second worker immediately went down to assist. However, he also succumbed to the gas and could not climb out. Local residents attempted to help by throwing ropes, but their efforts were unsuccessful due to concerns about their own safety. They then alerted authorities.

Police and rescue teams quickly arrived at the scene. Using oxygen masks, specialized ropes, and ventilation equipment, they accessed the manhole and brought the victims to the surface. Both workers were recovered with pale blue skin, indicating severe asphyxiation.

Rescue forces extracting the two victims from the manhole. *Residents provided*

A representative from Phu My Ward People's Committee confirmed that the two workers died from gas asphyxiation while inspecting the drainage system manhole. The incident occurred directly at the Ngoc Ha market entrance, located 20-30 meters from a nearby intersection, with the manhole opening measuring over 60 cm in diameter.

Experts explain that confined spaces like wells and sewers inherently have low oxygen levels. Furthermore, the decomposition of accumulated waste and animal carcasses in these environments produces dangerous toxic gases such as methane, hydrogen sulfide (H2S), and carbon monoxide (CO). Inhaling these gases can rapidly lead to unconsciousness and death.

Truong Ha