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Dale M.
2005-06-27, 3:08pm
Notes on Natural Gas and Propane Use.

By Dale Meisenheimer

Natural gas and propane are both natural occurring flammable gases found in or near most known oil reserves in the world.

Natural gas is gaseous in nature and is pretty much a composite of Methane (85% ) and other gases. Natural gas is also "lighter than air" so any leaking gas will generally dissipate in to the air and be carried away IF plenty of ventilation is provided.

Propane is a Liquid Petroleum Gas (LPG) when stored under pressure it turns into a liquid. As pressure is reduced it naturally evaporates into a vapor. Propane and other LPG are "heavier than air" and tend to pool in low areas and become a explosive mixture when mixed with air and a ignition source in provided. Propane used in low areas (basements) should always have appropriate "drain" so an escaping gas can escape and not pool. NO the water drain in basement floor does not qualify.

Natural gas is generally a piped in gas using extensive underground piping systems and is usually available in more populated areas.

Propane is most often stored in tanks and used in more rural settings to power stoves, heaters and gas powered refrigerators and some industrial applications. EXCEPT for the ubiquitous #20 gas cylinder found under the BBQ grill in urban America

Temperatures of these fuels used with oxygen and adjusted for neutral flame are as follows:

(Degrees C. - Degrees F.)

Propane 2,450 - 4,442
Natural Gas/Methane 2,350 - 4,262

Some reference materials will have other values varying by several hundred degrees. It depends who researched and wrote the reference’s. But in all cases Propane will be hotter than Natural Gas/Methane.

NATIONAL FIRE PREVENTION ASSOCIATION ( NFPA)

Using and storing these "gases" is regulated by the Nation Fire Protection Association ( NFPA) and or a set of local ordinances. A copy of the NFPA codes may be purchased here:

http://www.nfpa.org/Codes/index.asp

Note: They are not available for viewing online.

Or:

NFPA (National Fire Protection Association)
1 Batterymarch Park, Quincy, MA 02169-7471 USA
Telephone: +1 617 770-3000 Fax: +1 617 770-0700


The NFPA stipulates that natural gas may be brought into a residence in steel piping at a maximum pressure of 5 pounds per square inch (psi) . It is generally brought into residence at the pressure of ¼ to ½ psi or 6.9199 to 13.8399 inches of water column (wc). 27.6799 inches of wc is equal to 1 psi.

The NFPA stipulates propane may be brought into a residence at the maximum pressure of 20 psi . And must be in steel piping.

Please note it is against NFPA and most local ordinances to bring either gas into residence with rubber or vinyl hose just pushed through a hole in the wall.

The NFPA also prohibits storage and use of a propane cylinder over the size of "1 pound" in a residence. Although it is permissible to store 2 such "1 pound" containers inside at any give time. This means your 4.5 and 11 and 20 pound cylinders (or larger) MUST BE STORED OUTSIDE. If concerned about out side storage you can either provide a secured (locked) storage enclosure or if its only appearance you can use a decorative enclosure. Just be sure what ever enclosure you use, that it is well ventilated at bottom of enclosure to prevent propane pooling in enclosure.

GETTING “CONNECTED”

Note also that propane gas is normally at a pressure of about 100 psi when in a tank and stored at approximately 70 deg F. This is so whether it is in a 1 pound cylinder or the 2000 gallon tank behind local industrial building down the street. It is customarily to use a fixed regulator to bring down the pressure of propane to ¼ to ½ psi or 6.9199 to 13.8399 inches wc for appliance use in the residential setting. When used for lamp working purposes it is customary to use a working pressure from ½ psi to 10 psi. This is accomplished using a adjustable regulator, the same type used for acetylene/oxygen welding in the industrial world.

Bringing propane into home or extending natural gas into studio area should be done by a qualified professional plumber or HVAC person. It is usually required that a building permit be obtained from local building authorities and all work must be inspected once work is complete. This is for personal safety, insurance and liability reasons. Some states now require a "Gas Certified Plumber" to do the actual work.

At the end of the new “line” should be quality shut off valve. Also some type of adapters are required to get connected from the standard cut off valve to your particular hose type. A “Type B” fitting may be required (1/4" NPT to 9/16"-18 (B-Size)) may be required to connect a standard grade “T” welding hose to the new glass line. This fitting should be available at welding supply, if your plumber can not locate one in his supplies. Note that the fuel “b-fitting” is left hand thread ( has circular mark around wrench area). Or it may be possible to have “barbed” fitting placed on end of gas line and the hose just slipped over barbed fitting and clamped in place with metal ( mechanical) clamp.

Grade “T” welding hose or an “approved” propane type hose must be used (propane “rated” embossed or printed on hose) . Any other type of hose will be affected by the propane and will deteriorate and cause rubber particles to clog torch head and/or prematurely begin leaking causing extreme safety hazard.

A "gray" area I hesitate to mention is using a HOT HEAD torch on extended hose from a bulk tank. First the HOT HEAD was designed to be used on a 1 pound disposable propane or MAPP gas cylinder. It is a practice of some bead makers to use a extension hose intended for camping appliance's ( stoves and lanterns) to connect a HOT HEAD torch to a bulk fuel tank. The gray area is it violates the NFPA codes on bringing high pressure propane in to a residence. The common practice is to connect the hose to tank only during the period of time that the torch is in use. The tank must remain outside. The hose may be brought into the work are through a open door or window only during torch session. At no time is the hose and high tank pressure to be used as a permanent installation. It is recommended that the hose is disconnected from the tank after use and brought inside. The tank must stay outside.

As usual when working with any compressed gas fuels, use caution and have unobstructed access to emergency shut off. Keep exits clear, and have fire extinguisher easy accessible.

NOTE: This document is copyright © 2003-2005 by Dale Meisenheimer.
This document may not be reproduced on any other website or forum without express written permission by the author.


Rev 06-26-2005

chrisdd
2005-06-27, 7:27pm
Thanks, Dale...great info as always.

BillBrach
2005-07-03, 9:43am
Dale,

Is there an approved method to connect the "steel pipe" to the tank outside ??

It seems that this would need to be a flexible hose to allow for some movement of the tank, possibly a steel or stainless steel flexible line of some sort.

Many times I've seen "copper tubing coils" used in this location, I wonder if this is approved ??

Bill

Dale M.
2005-07-03, 9:58am
I think it was covered here....

http://www.isgb.org/forum/ubbthreads/showflat.php?Cat=&Board=safety&Number=61591&page=0&view=collapsed&sb=5&o=&fpart=1

All documentation I have seen seem to suggest Propane approved rubber hose....

Same as in RV installations(?).... Hose and specalized connectors may be available at RV dealers....

Also some interesting reading.... Don't know how much applies.....

http://ops.dot.gov/regs/small_lp/Chapter3.htm
http://ops.dot.gov/regs/small_lp/Chapter9.htm



Dale

BillBrach
2005-07-03, 5:19pm
Every RV installation I've ever seen have those rubber hoses in total darkness. Propane tank/tanks are either in a enclosed box near the hitch, or is under the unit.

In my opinion, it is better to be safe than sorry, as the sun will deteriorate them very quickly. So just make sure they are not subject to DIRECT sunlight.

Dale M.
2005-07-03, 5:30pm
I think it may be the aesthetics of the RV construction that puts them in the dark... What about rubber hoses on BBQ grills....

Dale

BillBrach
2005-07-03, 5:48pm
Dale,

Good point on the BBQ grills. But, notice that most BBQ tanks are under the grill, and often the rubber hose is NOT in the sun.

I was just trying to say that we KNOW the sun emits UV, and UV deteriorates rubber in several ways, so to be safe, TRY to keep it out of the sun.

Bill

Dale M.
2005-07-03, 7:01pm
Think we need to have a little more faith in the quality and longevity of the hose and the manufacturers.

Dale

MikeAurelius
2005-07-05, 6:33am
Absolutely Dale, but the people who wrote the code did not have faith in the people who USE the product - the belief was that some people would not bother to inspect the hoses from time to time, and only replace them when they outright failed (which could be catastrophic).

oldrosegarden
2006-02-27, 8:33am
Thanks for all this information. I think I have even more questions:
I'm about to buy a Nortel bench burner for use with a 20lb propane tank (barbecue probably) and oxygen. What exact instructions will I give the plumber (gas certified) who probably won't know a think about lampworking? It sounds like I have to tell him to that I want to bring it into the house at a pressure of 5 psi. Also, I don't understand everything here but I want to know the worst case scenario: if I have a gas certified plumber pipe propane into my basement and set up my torch with the standard propane regulator, will my house still blow up the first time I ever forget to turn off the outside valve on my propane tank?
Thanks so much for all your postings.

artwhim
2006-02-27, 9:31pm
My propane line was professionally installed. I like the fact that I have so many turnoffs. First there is the tank that is located outside. It has the standard on/off screw top. Then they installed a turnoff valve inside at the end of the metal pipe. Since it is a handle type it is easy to tell even at a distance if it is off. Then there is the torch valve.

I would insist on the wall valve. The added security is worth the price of installation. I actually think they are required to add this but not positive.

Good luck,
Kathy

Tanya
2006-03-07, 8:49am
Thanks for all the great information. Dale - this is something people really need to know about.

I'm feeling pretty overwhelmed right now. I'm trying to get hard connections installed outside for both propane and O2. We have an existing 100g tank of propane we use for a propane stove in the room next to my studio. I'd like to tap into this so I don't have to use the 20 lb tank anymore. I have a qualified person lined up to do the work, but he needs to know that this will be in conformance with my township's building codes. Now I have to deal with my township and the building code person. I left a message and am waiting for a call back.

I'm sure others out there have dealt with this before. Has anyone had a hard time getting approval? Is there anything I should know before talking to this man? I'm terrified they'll tell me I can't do lampworking in my home.....