Theodore C. Lemoff
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Many changes were made in the 2008 edition of NFPA 58, Liquefied Petroleum Gas Code. Major changes of interest to propane
marketers are listed here, with some reasons why they were made. A more complete list of changes has been included in the
2008 edition of the Liquefied Petroleum Gas Handbook, available from NFPA.
Cabinet heaters are not included. There has been extensive discussion of this subject, and therefore not included in this
article. Composite cylinders were not added to NFPA 58, but they can be used anywhere metal cylinders can be used, as they
are DOT cylinders, and NFPA 58 allows all DOT cylinders.
1. Temporary installations. The maximum duration of a temporary installation was changed to 12 months. In the 2004 edition, the definition of temporary
installations stated six months, but elsewhere in the code they were allowed to be 12 months. Enforcers believed that temporary
installations should be limited, and that any installations beyond six months should follow the permitting and approval requirements
of the code. Marketers agreed that there should be a limit to temporary installations, but believed that many truly temporary
installations, such as construction heating, required more than six months.
2. Notification of new railcar transfers. This new paragraph (4.3.2) requires that the authority having jurisdiction be notified of the first transfer from a railcar
in a new installation. Permitting has been required, but up until now the authority having jurisdiction might not have been
aware that product was being transferred until after some time. The requirement was requested by a local authority that inspects
new installations but was not notified of its startup. 3. 100-pound cylinders without fixed maximum-level gauges. Previously, all 100-pound cylinders were required to have a fixed maximum liquid level gauge (spit gauge). Many cylinders
in industrial gas service are filled by weight only. These do not have fixed maximum level gauges, and the industrial gas
companies that use them have a large inventory of such cylinders. The committee did not see why a fixed maximum liquid level
gauge should be required for cylinders used by companies that fill by weight. Marketers should be aware that they may receive
cylinders that do not have this gauge. These must be filled by weight.
Figure 1
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4. Container appurtenance table. The container appurtenance table (Table 5.7.4.1) was completely revised and simplified to have fewer columns and rows. The
table is used mostly by suppliers who provide cylinders complete with appurtenances (valves, level gauges, etc.).
Figure 2
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5. Threaded internal valves. A threaded internal valve in the open position (shown in Figure 1) is equipped with a manual operator. When this valve is
installed in a propane tank, it is threaded into an existing tank fitting. Newer tanks have a half-coupling welded to provide
the thread; older tanks use a full coupling. The flow though the internal valve will depend on the type of coupling. Figure
2 shows the same internal valve threaded into a halfcoupling. Figure 3 shows the same valve threaded into a full coupling.
Note the opening through which the liquid propane flows is within the coupling in Figure 3, restricting the flow of liquid.
The flow is not restricted with a half-coupling. Manufacturers of internal valves provide flow information for their valves
with different values for both situations.
