Within the rules and purpose of this forum --" the promotion of safe diving through accident analysis.
Accurate analysis of accidents and incidents that could easily have become accidents is essential to building lessons learned from which improved safety can flow."
Please...Remind yourself of the rules before you add to the thread...
(1) Events will be "scrubbed" of names. You may refer to articles or news releases already in the public domain, but the only name you may use in this forum is your own.
(2) No "blamestorming." Accident analysis does not "find fault" - it finds hazards - and how to reduce or eliminate them.
(3) No flaming, name calling or otherwise attacking other posters. ....etc.
Other threads that have attempted to discuss this accident have been locked/edited/or deleted because of posters not following the rules. It is my hope that this thread will remain constructive, instructional and maybe even save a life by discussing the danger of Carbon Monoxide (CO) and what can be done to prevent and detect it.
Backround from Scuba-Doc:
"Carbon Monoxide poisoning is a rare cause of problems when diving, it does occur when there is contaminated air in recreational diving tanks. CO poisoning is the leading cause of poisoning deaths in the U.S.(about 8600 deaths per year) and is easily missed unless health care providers are especially vigilant.
The most commonly observed result related to CO poisoning is neurological dysfunction; abnormalities in the cardiac, pulmonary and renal organ systems do occur. About 14% of patients sustain permanent brain damage, and delayed neurological sequelae do occur 3-21 days later in about 12% of people.
--------------------------------------------------------------------------------
CO risk factors include:
Pre-existing cardiovascular disease
Age greater than 60 years
An interval of unconsciousness (longer the higher the risk)
Little association with COHgb (carboxy hemoglobin)
Carbon Monoxide signs:
Tachycardia (rapid pulse)
Tachypnea (rapid breathing)
Retinal venous engorgement (as seen through an ophthalmoscope)
Ekg conduction defects
COHgb greater than 20%
--------------------------------------------------------------------------------
Carbon monoxide in diving is the product of incomplete combustion of hydrocarbons and is usually from compressors and cigarette smoking. In addition to the effect on the hemoglobin molecule, it has a toxic effect on the cytochrome A3 system. Prevention requires periodic air sampling. The maximal allowable level is 20 ppm (0.002%)"
In light of recent Roatan reports of 2 diver deaths on the same dive from "bad air" who were diving with a top dive resorts operation, I have been searching for answers to a few questions and would like to take every reasonable step to protect myself from a similar mistake.
---Are the symptoms of CO poisoning detectable by a diver in time to surface/abort the dive?
---If so what's the time frame for detection?
---What is the lethal ppm range?
---Do fill stations (resort or otherwise) routinely check for CO and measure ppm?
---If so how often?
---What is the best method for a diver to self test his tanks for CO?
---Does anyone manufacture a combination Nitrox/CO analyzer/detector?
Now, without flaming or naming....let's all learn something from one another and discuss CO poisoning. Thanks in advance for your thoughtful replys.
Accurate analysis of accidents and incidents that could easily have become accidents is essential to building lessons learned from which improved safety can flow."
Please...Remind yourself of the rules before you add to the thread...
(1) Events will be "scrubbed" of names. You may refer to articles or news releases already in the public domain, but the only name you may use in this forum is your own.
(2) No "blamestorming." Accident analysis does not "find fault" - it finds hazards - and how to reduce or eliminate them.
(3) No flaming, name calling or otherwise attacking other posters. ....etc.
Other threads that have attempted to discuss this accident have been locked/edited/or deleted because of posters not following the rules. It is my hope that this thread will remain constructive, instructional and maybe even save a life by discussing the danger of Carbon Monoxide (CO) and what can be done to prevent and detect it.
Backround from Scuba-Doc:
"Carbon Monoxide poisoning is a rare cause of problems when diving, it does occur when there is contaminated air in recreational diving tanks. CO poisoning is the leading cause of poisoning deaths in the U.S.(about 8600 deaths per year) and is easily missed unless health care providers are especially vigilant.
The most commonly observed result related to CO poisoning is neurological dysfunction; abnormalities in the cardiac, pulmonary and renal organ systems do occur. About 14% of patients sustain permanent brain damage, and delayed neurological sequelae do occur 3-21 days later in about 12% of people.
--------------------------------------------------------------------------------
CO risk factors include:
Pre-existing cardiovascular disease
Age greater than 60 years
An interval of unconsciousness (longer the higher the risk)
Little association with COHgb (carboxy hemoglobin)
Carbon Monoxide signs:
Tachycardia (rapid pulse)
Tachypnea (rapid breathing)
Retinal venous engorgement (as seen through an ophthalmoscope)
Ekg conduction defects
COHgb greater than 20%
--------------------------------------------------------------------------------
Carbon monoxide in diving is the product of incomplete combustion of hydrocarbons and is usually from compressors and cigarette smoking. In addition to the effect on the hemoglobin molecule, it has a toxic effect on the cytochrome A3 system. Prevention requires periodic air sampling. The maximal allowable level is 20 ppm (0.002%)"
In light of recent Roatan reports of 2 diver deaths on the same dive from "bad air" who were diving with a top dive resorts operation, I have been searching for answers to a few questions and would like to take every reasonable step to protect myself from a similar mistake.
---Are the symptoms of CO poisoning detectable by a diver in time to surface/abort the dive?
---If so what's the time frame for detection?
---What is the lethal ppm range?
---Do fill stations (resort or otherwise) routinely check for CO and measure ppm?
---If so how often?
---What is the best method for a diver to self test his tanks for CO?
---Does anyone manufacture a combination Nitrox/CO analyzer/detector?
Now, without flaming or naming....let's all learn something from one another and discuss CO poisoning. Thanks in advance for your thoughtful replys.