Here is a new article: (They mention that it was an aluminum tank, although who knows how accurate that is at this point.)
Scuba tank explosion raises questions among divers | wtsp.com
Written by Eric Glasser
St. Petersburg, Florida -- The Tampa Bay scuba diving community is rasing questions about a scuba tank explosion Sunday that killed a local dive instructor.
23-year-old Russell Vanhorn died when the blast ripped through a condo on 37th Avenue North.
Detectives say they're looking at all possibilities, including whether Vanhorn's aluminum tank was faulty, or whether the Iraq war veteran used his knowledge as a dive instructor to alter his dive tank in some way.
Some who knew him describe Vanhorn as an avid cave diver. In order to maximize their "bottom time" or time spent underwater, it's not unheard of for some divers to over-fill their scuba tanks.
Dive shop workers say a membrane called a "burst disk" in the valve-stem is supposed to prevent such over-filling. But a skilled dive technician like Vanhorn, they say, would know how to add an extra burst disk -- or perhaps a stronger one -- in order to fill the tank beyond its normal specs.
"If that's tampered with, the safety is tampered with. And if the pressure gets too high, it's got nowhere to go but through the tank wall," said Bill Hardman, owner of Aquatic Obsessions Dive Shop in St. petersburg, "And that's a bomb."
Police do not suspect foul play. They are speaking with two other people who were inside the apartment when the tank exploded to see what they know about the tank, when it was last serviced, whether it was over-filled, and who last pressurized the cylinder.
"We have heard -- not necessarily from them -- but we have heard in the past, that tank modification is not unheard of in those individuals that like to cave dive," said Spokesman Mike Puetz. "So, again, that's just one aspect of this we're going to be looking at."
Witnesses say Vanhorn was carrying the tank to his car for a dive trip when the explosion occurred.
Please note that by pasting in the text of the article I am not trying to discourage people from clicking on the link and reading the article at its source. I always try to do that and I often find the comments there interesting. But, in future, an A & I thread's usefulness can be compromised if the article links are "dead" and their text is not available (I have read some past threads where this was a problem).