The Volcanological Institute of the Canary Islands (Involcán) has warned that the amount of carbon dioxide (CO2) per unit area (square kilometer) emitted into the atmosphere by the La Bombilla area (0.033 square kilometers of surface) is of the order of 30 times higher than the amount of CO2 of the entire volcanic edifice of Cumbre Vieja (220 square kilometers of surface).
Currently, the La Bombilla area has an instrumental network for monitoring carbon dioxide (CO2) in the ambient air (outdoors) made up of five stations and, on occasion, the concentrations of CO2 in the ambient air (outdoors), at 30 centimeters from the ground, they register more than 40,000 ppm, the upper limit that sensors can detect.
In addition, they are registering average daily values of CO2 between 10,000 ppm and 30,000 ppm, with concentrations that are even observable with the naked eye. In the case of the station that operates Involcán, daily average values of CO2 have been recorded between 50,000 ppm and 215,000 ppm. This figure is much higher than what is considered lethal for humans.
Outdoors and in poorly ventilated areas, as occurs in some parts of La Bombilla, repeated exposure to CO2 concentrations between 30,000 ppm and 50,000 ppm causes headaches and the respiratory rate accelerates, but this is lethal in the case of exposure to CO2 concentrations of the order of 150,000 ppm.
Currently, the Puerto Naos area has 7 stations in indoor areas of buildings and outdoors. As in La Bombilla, the monitoring stations in Puerto Naos exceed the value of the upper limit that their sensors can detect, registering average daily values of CO2 between 5,000 ppm and 30,000 ppm and up to 40,000 indoors. The residence time for people indoors should not exceed 30 minutes if CO2 concentrations are between 5,000 ppm and 25,000 ppm and immediate ventilation is recommended.
The Involcán has recently installed in Puerto Naos a non-instrumental network of 40 observation points inside buildings (ground floor at street level) thanks to the collaboration of owners and administrators of the area with the aim of evaluating a possible zoning of this volcanic hazard in Puerto Naos. This network of alkaline traps does not provide information on the concentrations of CO2 inside the buildings, but it does allow knowing the amount of CO2 that can be trapped in them, registering for the most part values greater than 120 milligrams per day, reaching to register in some observation points values higher than 200 milligrams per day, above the value considered acceptable for health.
