2438                               Municipal Charters

The following diversity factors may be used in determining gas
piping size to be used in multiple family dwellings.

EQUIPMENT IN EACH UNIT

		Range	Range,		Auto Water
		and Auto.	Auto Heater	Range	Heater
No. of	Range	Water	and	and Cent.	and Cent.	Cent.
Units	Only	Heater	Cent. Heat.	Heat	Heating	Heat Only
1 to 4	1.00	1.00	1.00	1.00	1.00	1.00
5 to 10	.70	.75	.80	.80	.85	.95
11 to 15	.45	.50	.65	.75	.80	.90
16 to 30	.40	.45	.65	.70	.75	.85
31 or more	.30	.40	.65	.65	.70	.80

NOTE: The above diversity factor is a multiplier for the total
input of all connected appliances served by any single section of piping
(see Table). The "number of units" is taken as the number supplied by
the particular section of piping under consideration.

(6)    Subsection 2.4.5. Additions to Gas Piping. Delete from the
first and third sentences the letters, "A, 2B, 2C" and from the first
sentence the words "whichever is designated by the serving gas supplier."
Add at the end the following: "Additions to existing pipe may also be
sized according to Subsection 2.4.3 (d)".

(7)    Subsection 2.6.1. Piping Material. Delete from (a) the second
and third sentences and the footnote marked by "**".

(8)    Subsection 2.8.3. Piping in Floors. Delete as written and sub-
stitute the following: "Gas piping in solid floors such as concrete shall
be laid in channels in the floor suitably covered to permit access to the
piping with a minimum of damage to the building. When piping in floor
channels may be exposed to excessive moisture or corrosive substances,
it shall be suitably protected."

(9)    Subsection 2.9.2. Protection Against Corrosion. Delete from
2.9.2 (b) the words "or Table 2B, as designated by the serving gas
supplier".

(10)    Subsection 2.10.2. Gas Piping to be Graded. Add to this
subsection the following: "Where it is not possible to grade lines as
described, special written permission must be received from the Adminis-
trative Authority for the installation of approved drip."

(11)    Subsection 2.10.9. Use Tee. Delete as written and substitute
the following: "A tee fitting with the bottom outlet plugged or capped
shall be used at the bottom of any pipe riser or drop to appliances except
where there is any danger of freezing. (See Figure 1)."

(12)    Subsection 2.10.13. Prohibited Devices. Renumber present
paragraph as paragraph (a) and add (b) as follows: "(b) No bushings
with a reduction of one pipe size, close nipples or all threads shall be
used in any gas system."

(13)    Subsection 2.10.15. Electrical bonding and Grounding. Delete
entire subsection.

(14)    Subsection 2.13.2 (a). Delete last two sentences of second
paragraph starting with "Allow five ....:" and ending with "the upstroke",
and substitute the following sentences and Table 2.13.2:

The length of observation time shall be as shown in Table 2.13.2.
This observation should be made with the testhand on the upstroke.