Are hydros really necessary?

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I think the danger of missing a hydro test by a couple of years is being overstated on this thread, especially if the tanks in question were relatively new AL tanks. To my knowledge there has never been a documented example of a 6061 AL scuba tank filed with air exploding. The horror stories are usually about the older AL alloy, badly rusted steel tanks, or tanks filled with high percentage O2.

The shop's neglect is definitely illegal, but if the tanks were as described, were they dangerous to divers on the boat? Almost certainly not; probably a bigger chance of getting struck by lightning than having an already-filled tank explode on board simply because the hydro was out of date.

If I was on the boat, I would have done what the OP did; alerted the DM, and simply continued the dive. I would not go back to that shop, but I wouldn't let it ruin a good day of diving.

The tanks exploding referenced as 'horror stories' were not that old when they happened. You're right tho, in reality the danger is most likely overstated. But do you know which tank out there is about to fail hydro? Chances are it's not yours of one you will ever see but it could be.

Playing the odds with what is essentially an explosive device is not only dangerous but highly illegal. Purposely missing hydro's opens the door to big fines and loss of business if you're a LDS. 6061 tanks are relatively safe but year after year tanks get older and weaker. Metal fatigue is more likely and so is mistreatment of tanks (known or unknow).
 
I stand corrected. The Department of Transportation NOT ONLY requires the cylinder to be hydrotested if transported on any public roadway (in commerce) but also if it is NEVER transported in commerce. Here is a quote from DOT. "Any cylinder marked to certify that it conforms with the HMR must be maintained in accordance with applicable specification requirements whether or not it is transported in commerce at any particular time."

The link to the letter of interpretation is below. Keep in mind, letters of interpretation are incorporated by reference into DOT's requirements for cylinders.

Right Here -----> Updates and Interpretations that affect Cylinder testing Click on 'Cylinders "not transported in commerce"

I believe you may be misinterpreting this letter. None of my tank are marked to certify that they conform with HMR requirements. Nor have I ever seen a scuba tank so marked. Therefor A1 make it clear that they are not covered.
 
I believe you may be misinterpreting this letter. None of my tank are marked to certify that they conform with HMR requirements. Nor have I ever seen a scuba tank so marked. Therefor A1 make it clear that they are not covered.

If you're in the United States and I'm assuming TX in this case means Texas, your SCUBA cylinder will say something like DOT 3AL-3000 or DOT 3AA-2400. These are both Department of Transportation markings, and are covered under 49 CFR sections 180.1 to 180.201 roughly. Any cylinder in this category, must be maintained according to its specificion (reference above DOT specifications) including hydrostatic testing.

Any hydrostatic testing stamp on any of your SCUBA cylinders, including the manufacture, certifies that they conform with the HM R. The HMR is incorporated by reference into Title 49 of the Code of Federal Regulations (49 CFR).
 
If you're in the United States and I'm assuming TX in this case means Texas, your SCUBA cylinder will say something like DOT 3AL-3000 or DOT 3AA-2400. These are both Department of Transportation markings, and are covered under 49 CFR sections 180.1 to 180.201 roughly. Any cylinder in this category, must be maintained according to its specificion (reference above DOT specifications) including hydrostatic testing.

Any hydrostatic testing stamp on any of your SCUBA cylinders, including the manufacture, certifies that they conform with the HM R. The HMR is incorporated by reference into Title 49 of the Code of Federal Regulations (49 CFR).

While I agree with your idea that DOT tends to mealy-mouth their interpretations, I think it is fairly clear that the "markings" referred to in your cited letter are those markings required by the HMR, Part 172, Subpart D, which are the marking which pertain to the contents for the specific shipment.
 
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I stand corrected. The Department of Transportation NOT ONLY requires the cylinder to be hydrotested if transported on any public roadway (in commerce) but also if it is NEVER transported in commerce. Here is a quote from DOT. "Any cylinder marked to certify that it conforms with the HMR must be maintained in accordance with applicable specification requirements whether or not it is transported in commerce at any particular time."

The link to the letter of interpretation is below. Keep in mind, letters of interpretation are incorporated by reference into DOT's requirements for cylinders.

Right Here -----> Updates and Interpretations that affect Cylinder testing Click on 'Cylinders "not transported in commerce"

Edit: I just saw your recent posts which were made while I was composing this post. Please read with that in mind)

What does it mean for a cylinder to be marked to indicate manufacture in accordance with requirements established in the HMR? Is it the "3AA" stamp? REE stamp? What?

If it is a stamping on the cylinder, then according to the letter that stamping must be "removed, obliterated, or securely covered" if empty and offered for commerce (see A6). This, right after she says the empty cylinder is not even subject to the HMR! If it isn't subject to the HMR, then how can the HMR to which it is no longer subject require that markings be "removed, obliterated, or securely covered"?! Makes no sense.

Furthermore, at the beginning of the letter she said, "Thus, a DOT specification 3AA, 3AL, or other SCUBA cylinder that is marked to indicate conformance with applicable DOT requirements must be retested and otherwise maintained in accordance with the HMR whether or not it is being used to transport hazardous materials in commerce."

So, wait.....a depressurized cylinder is NOT a "hazardous material", and is NOT "subject to the HMR" according to her own statement, but here it IS subject to the HMR while NOT being used to transport hazardous materials (being unpressurized) in commerce??? Again, nothing she says makes sense. She contradicts herself, which makes me question the authority of her interpretations.

The idea that a cylinder sitting in my garage MUST be retested and otherwise maintained in accordance with a Federal regulation is draconian at best, and I doubt it would hold up in court. Perhaps Miss Gorsky would be more in her element in Russia?
 
Could you provide the reference for that definition. I suspect something has been left out.

When a 2 Y/O trades her doll with her 2 Y/O cousin is it intrastate commerce if they both live in the same state but interstate commerce if one is visiting from out of state?

It is intrastate commerce if they trade dolls while they are together. Like when you buy groceries when visiting another state.

---------- Post added October 16th, 2014 at 08:35 PM ----------

By law (49 CFR), any compressed gas that has a pressure of 40 PSI or higher is considered Hazardous Materials.

---------- Post added July 24th, 2014 at 07:07 AM ----------




Placards are only required when the transported HAZMAT exceeds the "minimum reportable quantity". For non flammable/non poisonous compressed gasses the minimum reportable quantity is 1000lbs combined weight of HAZMAT and packaging. For example, this equals approximately 28 filled AL80 tanks. The number will vary depending on if you are carrying steel tanks, composite cylinders, pony bottles, or a combination of all of the above. Dive shops would have to then placard the vehicle with a Class 2 Nonflammable gas placard, and if carrying O2 bottles or Nitrox also placard with a Class 2 Oxygen placard. Depending on state regulations, the transporting entity will also be regulated on what documentation, and drivers license they need.

For quantities of air/nitrox/O2 under 1000lbs (combined weight of HAZMAT and packaging) placarding is not required.

See 49 CFR, Part 172, Subpart F for complete placarding regulations.

At 1000 lb contents and containers above 40 psi it is obvious that the tires on a tractor trailer need to be placarded.
 
The Department of Transportation requires any tank, scuba or otherwise to be tested every 5 years (with unrelated exceptions). You can look up specific rulings on ctcseminars.com that's the easiest place I was able to find it.
So no joe blow will probably not be fined when he's filling his tank. However, DOT specifies in its ruling that any tank transported in commerce is subject to the HMR (hazardous materials register) aka 49 CFR ( code of federal regulations ) and therefore must be tested at 5 year intervals. This means that if you drive with your cylinder on ANY public roadway and I knew 99.9% of people do, you are IN commerce and must have your tank tested.

this is one thing I'll never understand about this industry. Why would you chance killing yourself or someone else to save 25-30 dollars every 5 years. You're breaking the law and any fine, if you survive the accident, will be much more than you could possibly ever spend on hydrotesting.

Wrong. Please leave the lawyering to the lawyers. TYIA.

Jesus, do you people even read the :censored:ing documents you cite before you cite them? See 7/1/2005 DOT response letter cited by GrainDane above, which says on page one that "the HMR requirements applicable to pre-transportation functions do not apply to the transportation of a cylinder by a private individual for personal use." (emphasis added).

Also bear in mind that the DOT's cutsie attempt at circumventing a simple 'yeah, HMR requirements don't apply to private use'--the claim that HMR compliant marked cylinders must be maintained as compliant whether used in commerce at that moment or not--is making artful use of the passive voice for a reason. That reason is that simply owning a tank with such markings doesn't confer any obligation to comply with DOT regs or rules on a private individual not engaged in interstate commerce. DOT may construe the regs to require marked tanks to be maintained however they want...but their rules do not apply to and they have no lawful authority to enforce that requirement against someone not engaged in interstate commerce. Perhaps they'll issue a citation to the tank itself.
 
Edit: I just saw your recent posts which were made while I was composing this post. Please read with that in mind)

What does it mean for a cylinder to be marked to indicate manufacture in accordance with requirements established in the HMR? Is it the "3AA" stamp? REE stamp? What?

If it is a stamping on the cylinder, then according to the letter that stamping must be "removed, obliterated, or securely covered" if empty and offered for commerce (see A6). This, right after she says the empty cylinder is not even subject to the HMR! If it isn't subject to the HMR, then how can the HMR to which it is no longer subject require that markings be "removed, obliterated, or securely covered"?! Makes no sense.

Furthermore, at the beginning of the letter she said, "Thus, a DOT specification 3AA, 3AL, or other SCUBA cylinder that is marked to indicate conformance with applicable DOT requirements must be retested and otherwise maintained in accordance with the HMR whether or not it is being used to transport hazardous materials in commerce."

So, wait.....a depressurized cylinder is NOT a "hazardous material", and is NOT "subject to the HMR" according to her own statement, but here it IS subject to the HMR while NOT being used to transport hazardous materials (being unpressurized) in commerce??? Again, nothing she says makes sense. She contradicts herself, which makes me question the authority of her interpretations.

The idea that a cylinder sitting in my garage MUST be retested and otherwise maintained in accordance with a Federal regulations is draconian at best, and I doubt it would hold up in court. Perhaps Miss Gorsky should go back to Russia?

1) For a cylinder to be marked to indicate manufacture in accordance with the HMR

Any DOT stamp you see on your cylinder (DOT 3AL-3000) is a stamp that manufactures are allowed indicating the cylinder is a DOT certified cylinder made of Aluminum with a service pressure of 3000 psi. *The REE (for example REE 78) indicates that the cylinder cannot have an elastic expanision of more than 78 ml during hydrostatic testing or it is rejected. REE stands for Rejection Elastic Expansion. This is used to determine if your tank can get the coveted + marking

2) Response to '...whether or not it is being used to transport HAZARDOUS materials in commerce. This means the cylinder must be retested and maintained if it contains compressed gases, whether or not it is being transported. Compressed gases are HAZARDOUS materials according to DOT and PHMSA (see Title 49 Code of Federal Regulations - Parts 180.1 to 180.201 for this topic). So any SCUBA, SCBA, CO2, Spare Air, etc cylinders are subject to DOT, PHMSA, and the HMR.

3) A depressurized cylinder

She states that a depressurized cylinder is NOT a "hazardous material", and is NOT "subject to the HMR". The limit as she states is 40 psi. This is because it is not CONTAINING any compressed gases - see hazardous material (i.e., air, Nitrogen, CO2). The moment it is going to be used as a vessel of hazardous material transportation, like when any SCUBA tank is filled, it is subject to the HMR. That is why NO tank out of hydro can legally be filled in the U.S.

3) Court & Your 'Garage' Cylinder

Yes, your cylinder MUST be retested. It is a compressed gas vessel and is subject to many, many regulations. As I've seen before on these forums, only "a handful of unlucky people" have died from tank explosions. When remove the amount of people that do follow industry standards, the percentage gets much bigger.

As for court, if you're willing to go up against the Department of Transportation to keep an explosive container in your garage - one that could easily destroy it, assuming your garage can't comfortably fit an airplane - then be my guest. Just know the manufacturer of said tank will not come to your aid. In fact, they will probably be at the court - telling the judge how the tank should have been maintained.

---------- Post added October 16th, 2014 at 10:54 PM ----------

Wrong. Please leave the lawyering to the lawyers. TYIA.

Jesus, do you people even read the :censored:ing documents you cite before you cite them? See 7/1/2005 DOT response letter cited by GrainDane above, which says on page one that "the HMR requirements applicable to pre-transportation functions do not apply to the transportation of a cylinder by a private individual for personal use." (emphasis added).

Pre-transportation means you don't need placarding and shipping within an outside package. (i.e. box, crate, etc). We weren't talking about placarding because we're talking about personal use. Take a few more seconds to read cited response letter.

We're talking about maintaining the cylinder - hydrostatic testing - and that is REQUIRED. Unless you want to make the same old argument, well what if its not beind used? Yes, assuming there is less than 40 PSI in the cylinder, as far as PHMSA and DOT are concerned it is a windchime. Just like a condemned cylinder.

---------- Post added October 16th, 2014 at 10:56 PM ----------

It is intrastate commerce if they trade dolls while they are together. Like when you buy groceries when visiting another state.

---------- Post added October 16th, 2014 at 08:35 PM ----------



At 1000 lb contents and containers above 40 psi it is obvious that the tires on a tractor trailer need to be placarded.

Tractor trailer tires are not DOT specification cylinders so the regulations we're talking about don't apply.
 
The moment it is going to be used as a vessel of hazardous material transportation, like when any SCUBA tank is filled, it is subject to the HMR. That is why NO tank out of hydro can legally be filled in the U.S.

Again, false. You don't understand the regulations you're citing, the DOT's letter interpreting them, or the interstate commerce precedents that undergird the system. Filling an out of hydro tank--whether you're a dive shop or Joe Blow with a compressor--is not illegal unless you're doing so as part of interstate commerce or transportation...though doing so is not very bright.

---------- Post added October 16th, 2014 at 09:03 PM ----------

Pre-transportation means you don't need placarding and shipping within an outside package. (i.e. box, crate, etc). We weren't talking about placarding because we're talking about personal use. Take a few more seconds to read cited response letter.

We're talking about maintaining the cylinder - hydrostatic testing - and that is REQUIRED.

Keep digging that hole, champ. From the same letter: "Q1. Do the HMR apply to a cylinder that is transported to and from a dive shop by a private individual for personal use?

A1. The HMR generally apply to the transportation of hazardous materials in commerce. Transportation of hazardous materials by a private individual in a private motor vehicle for personal use is not commercial transportation."

Then the DOT launches into the use of passive voice about tank labeling and maintaining such tanks whether or not it is in transportation in commerce at any particular time. And again, regardless of who can get in trouble for not maintaining such a tank in such a manner, it's not Joe Blow driving around with a filled and out of hydro tank, because the DOT has no authority over him in that context.
 
Again, false. You don't understand the regulations you're citing, the DOT's letter interpreting them, or the interstate commerce precedents that undergird the system. Filling an out of hydro tank--whether you're a dive shop or Joe Blow with a compressor--is not illegal unless you're doing so as part of interstate commerce or transportation...though doing so is not very bright.

Read cited letter again. A cylinder may not be filled unless it conforms with the HMR. By cylinder I mean any cylinder that was made by an approved manufacturer - these are the DOT markings. Only these cylinders are allowed to have DOT markings on them.

And again, it does not have to be a part of interstate commerce or transportation. It is still illegal. Like the letter says, whether or NOT it is being offered for transportation in commerce. NOT means you don't have to be transporting it for the regulations to apply.

NO cylinder may be filled if it does not have a current hydrostatic test from an authorized hydrostatic tester licensed under PHMSA with a valid Retester Identification Number (RIN).

---------- Post added October 16th, 2014 at 11:21 PM ----------

Keep digging that hole, champ. From the same letter: "Q1. Do the HMR apply to a cylinder that is transported to and from a dive shop by a private individual for personal use?

A1. The HMR generally apply to the transportation of hazardous materials in commerce. Transportation of hazardous materials by a private individual in a private motor vehicle for personal use is not commercial transportation."

Then the DOT launches into the use of passive voice about tank labeling and maintaining such tanks whether or not it is in transportation in commerce at any particular time. And again, regardless of who can get in trouble for not maintaining such a tank in such a manner, it's not Joe Blow driving around with a filled and out of hydro tank, because the DOT has no authority over him in that context.

Your argument is moot. Does the HMR apply to that personal cylinder with personal transportation to/from the dive shop?

The DOT does have authority over him. He is driving around with an article of 'hazardous material' that was marked at it last date of hydrotest to certify it CONFORMED WITH THE HMR. Therefore, the cylinder is subject to the HRM whether or not it is being transported in commerce.

You cannot fill an out of hydro cylinder, thus it will not be transported as a hazardous material. It cannot be transported full because it was marked at one point or another to certify that it complied with the HMR. In other words, that cylinder is OK for 5 years. When that 5 years is up, the cylinder (that was marked to conform with HMR and MUST be maintained accordingly) does not conform with the HMR and is illegal.
 
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