LNG Border

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augie47

augie47

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For installation of a non-classified pole light what would be the minimum distance from an above ground LNG storage tank ??
 
Augie, if situation (tank) being only for storage, and (non-dispensing device) Article 515.1 Scope. along w/Table 515.3 (outdoor equipment)
 
Thanks. I had referenced 515.3 but was not sure that was applicable for LNG,
 
If you have it available, consider NFPA 59A, especially Section 6. Several plant design references for spacing from potential "ignition sources" exist.

Edit Add: There are other considerations beyond electrical classifications.
 
NFPA59A specifies 15 ft from tank to be Class I Div 2. Also note if it’s a LNG facility that connects to a pipeline (ie governed under 49CFR 193) then it is the 2001 NFPA 59A that applies even though there are later editions.
 
I think answer to your question in OP is going to be dependent on whether there is any dispensing and filling operations at the tank location as well as where any pressure relief venting might be located. If dispensing/filling is at a location that is piped away from tank itself there may not be any classified location and pressure relief could possibly be piped away from the tank as well, even if just straight up to a higher elevation, that might be enough in some cases to lessen classification necessary at ground level.
 
kwired said:
I think answer to your question in OP is going to be dependent on whether there is any dispensing and filling operations at the tank location as well as where any pressure relief venting might be located. If dispensing/filling is at a location that is piped away from tank itself there may not be any classified location and pressure relief could possibly be piped away from the tank as well, even if just straight up to a higher elevation, that might be enough in some cases to lessen classification necessary at ground level.
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Straight up to a higher elevation is problematic since propane, unlike natural gas, is heavier than air. So the results would be dependent on cross ventilation.

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GoldDigger said:
Straight up to a higher elevation is problematic since propane, unlike natural gas, is heavier than air. So the results would be dependent on cross ventilation. Sent from my Pixel 4a using Tapatalk
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not propane. LNG. Although that vapor can also be heavier than air until it warms up.
 
Folks, we are discussing LNG (Liquified Natural Gas). As nhee2 notes, it can act as a heavier-than-air gas until it vaporizes. (See NFPA 497, Sections 4.2.1, 4.2.4, and 4.4.5) This is why I noted in my previous post (#5) that there are other NFPA 59A spacing considerations beyond electrical area classification.

While nhee2 is also correct that 49CFR 193 uses the 2001 Edition of NFPA 59A, FedOSHA can, and often does, use any Edition it deems relevant to the installation under the "General Duty" clause if it identifies a problem as a "recognized hazard".
 
rbalex said:
Folks, we are discussing LNG (Liquified Natural Gas). As nhee2 notes, it can act as a heavier-than-air gas until it vaporizes. (See NFPA 497, Sections 4.2.1, 4.2.4, and 4.4.5) This is why I noted in my previous post (#5) that there are other NFPA 59A spacing considerations beyond electrical area classification.

While nhee2 is also correct that 49CFR 193 uses the 2001 Edition of NFPA 59A, FedOSHA can, and often does, use any Edition it deems relevant to the installation under the "General Duty" clause if it identifies a problem as a "recognized hazard".
Click to expand...
The area classification tables in the 2001 edition are more prescriptive than those in the latest edition(s) - and fairly conservative (in my opinion). I think they should have left them as-is...(as-was)
 
Gentlemen, indeed this has been interesting read (after the fact) I believe, LGN being classified Class I Div. II. I based my first/second responses on 2020 addition, NFPA 70.

First viewing Table 514.3(B)(2) Dispensing Devices.
LGN- (Extent of Classified Area) Class I Div. II (10' all directions, Dispensing enclosure.).

*Then realizing after re-read, possible discription could be storage tank.
Article 515 Bulk Storage.
Table 515.
Outdoor Equipment-
-Division II -
(3') above floor or grade level, within (3' to 10') horizontally from edge of such equipment.

OK, so how does the "Regular Joe" Electrician & Field Inspector (AHJ) determine difference between (?) Obviously, we're going to reference the NFPA 70.

*Why is there such discrepancy between these two different NFPA Text, in a differental distance of an additional 5' (five foot)..
*And why doesn't the NFPA 70 account for the addional.
Obviousness, I don't own copy NFPA 497 or 59A.
 
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