Installer credentials for medium+ pressure gases piping installations? 1

[PagoMitch]

Could anyone point me to a standard or certification for installers for specialized gases?

NFPA 55 does a great job of calling out what needs to happen; but nothing even hinted at for qualifications of installers.
NFPA 99 (covering Health Care Med Gases) specifies ASSE 6000 series installers, testers, and verifiers, but those gases (O2, Med Air, N2O) are relatively tame, at pressures of 55-100 psi.
The AWS (American Welding Society) has installer certifications for welding and brazing tasks, but nothing on general installation/testing certifications for industrial gases.
A sub-group of the CGA (the CGACB) offers certification for bulk compressed medical gas supply systems - but nothing outside that narrow area of discipline.

This project has multiple gas lines: Acetylene at 10 psig, Methane at 1200 psig, O2 at 1200 psig, UHP Argon, UHP Nitrogen, Helium, and a couple more. The opportunities for errors will be many.

Other than specifying "Shall be installed in accordance with NFPA 55", I'd like to ensure that the Contractor has a working knowledge about the systems - and dangers therein - he will be installing.

TIA.

 

[1503-44]

That's usually an item of the bid evaluation and selection of winner procedure.
Contractor's experience.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[PagoMitch]

1503-44 - Unfortunately, the "bid evaluation" has generally taken a back seat to cost. Around here, the lowest cost/best talking Contractor is often more successful than the higher cost/better qualified Contractor. Hence my efforts to try and get ahead of this; these gas systems are not for the un-initiated to learn via OJT...
We (the A/E) seldom have input into the bid process; only how it turned out. Absent pre-qualifications - that I am trying to find - or create - only then do we discover the winning Contractor's name - and expertise.

 

[1503-44]

There is no universely accepted certification. If I managed to find something, you would not find a contractor with the credentials. Check your state's construction contractor licensing procedures, first,for if there is one.

As such, this is left up to your initiatives.

Contractor experience issues can also fall into the Contractor and supplier "prequalification actuvities". Do not send material inquiries or invitations to bid to any organisation not on the list.

You must convince your client and your management that potential risk of working with unqualified contractors on what you think is technically a difficult and potentially risky job is worth the prequalification effort.

Otherwise...
The answer then becomes,
"You will get what you pay for."

Find a construction contractor that will assign a PE to your job full time. Make that a line item in the construction contract.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[EngrPaper]

When using outside contractors for tubing systems, where I used to work would make each fluid tech do test bends and flares to be submit for inspection prior to work being done. Had more than a few contractors kicked off the job when you could tell they sent conduit benders and not pressure tubing folks.

 

[1503-44]

Good idea. Even very experienced pipeline contractors must have their welders qualified on test welds and a certain percent of production welds are continuously tested. You can't Count on much continuity in construction laborers between jobs, sometimes on the same job.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[EdStainless]

You have three very different piping requirements here.
You may want three different sets of qualifications.
The UHP systems are more akin to biotech or pharmaceutical services. These are normally done in SS with semi-auto orbital butt welds.
Lots of cleanliness and purge requirements. For tips look at ASME BPE.
The 1200psi services are clearly Code piping (or tube) installations.
The acetylene would be like any other med pressure flammable gas line (methane or hydrogen).
The installation methods may be very different, and the NDT and inspection requirements will be also.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[Prometheus21]

1503-44 is correct, there is no universal certification for installing specialized gases, beyond your typical cylinder safety and usage courses (to my knowledge).

As you say the opportunities for error will be many. In my experience the safest bet is to describe, in complete detail, what you need. Technical drawings and assembly documents needs to be clear-cut with no room for misinterpretations. Any and all deviations from your specifications will be on the shoulders of the contractor. (Then again, Im from Europe, probably a bit different).

In cases where I've organized the complete installation of cylinder filling systems the following needs to happen to reduce the risk of installation errors:

1. Any and all equipment in direct contact with the gas needs to arrive on sight ready for installation, if possible. This means everything shall be welded, brazed, bent, cleaned and packaged acc. to relevant rules and regulations before it arrives on sight. Inspection and product certificates will follow each piece of equipment according to your required specifications.

2. Due to the O2 system the entire area needs to be cleaned and prepped beforehand. Sectioned off areas should be available for storing the equipment meant for installation, reducing the risk of recontamination.

3. The technicians needs to follow appropriate cleanliness routines before starting the installation process. The use of lubricants, teflon tape on tapered threads, gaskets, O-rings and applicable torque values should be readily available for the technicians, to mention a few.

4. After that it's a simple matter of connecting everything together and performing a final inspection (is everything where it needs to be). The system needs to be pressurized and purged with oil-free air or nitrogen to clean out any residue that might have been introduced in the system, and check for any leakage that might occur. Additional leakage testing with Helium might be required.

I will assume the people who will use this system on a daily basis is trained and will know what they are doing.

As for the technicians:

"You must convince your client and your management that potential risk of working with unqualified contractors on what you think is technically a difficult and potentially risky job is worth the prequalification effort." -This

 

[FacEngrPE]

Consider adding these documents to your reading list.
NFPA 51 Standard for the Design and Installation of Oxygen-Fuel Gas Systems for Welding, Cutting, and Allied Processes
ASTM
MNL36-2ND-EB - Safe Use of Oxygen and Oxygen Systems: Handbook for Design, Operation, and Maintenance: Second Edition
ASTM G88-21 -Standard Guide for Designing Systems for Oxygen Service
ASTM Oxygen Training
Your 1200 psi gases may all need to be cleaned for oxygen service. That should suffice for the UHP gas service. It is easier to install clean and keep it clean, than to clean after installation.
MIL-DTL-24800, DETAIL SPECIFICATION: CLEANING COMPOUND - AQUEOUS - OXYGEN SYSTEMS COMPONENTS
MIL-STD-1622B STANDARD PRACTICE FOR CLEANING OF SHIPBOARD COMPRESSED AIR SYSTEMS
MIL-STD-1330 Revision D:1996 STANDARD PRACTICE FOR PRECISION CLEANING AND TESTING OF SHIPBOARD OXYGEN, HELIUM, HELIUM-OXYGEN, NITROGEN AND HYDROGEN SYSTEMS

 

[Caloooomi]

Reference EIGA / CGA standards? Not necessary qualifications, but at least there are guidelines to follow.

 

[PagoMitch]

Thanks again all.

I have created a Spec with pre-qualification data, as well as incorporated criteria from several of the indicated sources.
A lot of good references there.