Three security guards guarding a bank in Mangaluru were found dead by staffers who reached the branch on Tuesday morning.
The three men were posted at the Kotekaru Vyavasaya Seva Sahakara Bank, an agriculture credit co-operative bank near Mangaluru were found dead inside by staffers when they reached the branch.
Media reports identified the deceased as Umesh (60), Somnath (58) and Santosh (40) hailing from Mangaluru, Kolya and Manjanady respectively.
As the region was experiencing heavy rainfall along with thunderstorms, it was initially suspected that the three men had died due to a lightning strike.
However, later a forensic expert confirmed that they died after inhaling carbon monoxide emitted by the diesel generator. Lack of ventilation is suspected to be the cause of the poisoning.
"With all doors shut, the fumes emanating from the generator would have rendered them unconscious and continued inhalation caused asphyxiation. Their symptoms are similar to carbon monoxide inhalation," TR Suresh, Mangaluru City Commissioner told The Times of India.
CCTV footage showed that the three men were seen talking till 9:30pm on Tuesday. They had finished eating dinner at 8:30pm. It was after that one of them turned on the generator following a power cut.
Police are investigating a case of death by negligence under section 304A of the Indian Penal Code. Reports said that a huge number of people gathered at the spot as the news spread.
Carbon monoxide poisoning
Carbon monoxide (CO) is identified as a colourless, odourless, tasteless, non-irritating, but significantly toxic gas by an article in the Indian Journal of Critical Care Medicine. The article also states that it is one of the leading causes of accidental poisoning as the symptoms are similar to that of other common ailments.
The gas is known to combine with the haemoglobin in our blood to form carboxyhaemoglobin replacing oxygen from the blood. Symptoms vary from headache, nausea, convulsions to dizziness based on the amount of exposure.
1.28% or 12800 ppm presence of the gas in air can cause death in less than three minutes.
Accidental deaths owing to carbon monoxide poisoning have been reported in several cities across India. In 2006, three techies in Chennai died after inhaling carbon monoxide when their car was stuck in a traffic jam. A similar incident was reported in Thiruvananthapuram in 2007 when three youngsters had suffocated to death in a garage after inhaling carbon monoxide.
In 2007, Indian Express reported that LPG water heaters were to blame for at least a dozen carbon monoxide deaths that occurred in bathrooms in Bengaluru.