371
Pipeline and Haz. Matls. Safety Admin., DOT
§ 172.102
the ‘‘T’’ Code. If a frangible disc is re-
quired in series with the reclosing pres-
sure relief device for the specified port-
able tank, the alternative portable
tank must be fitted with a frangible
disc in series with the reclosing pres-
sure relief device; and
(D) With regard to bottom openings—
(
1
) When two effective means are
specified, the alternative portable tank
is fitted with bottom openings having
two or three effective means of closure
or no bottom openings; or
(
2
) When three effective means are
specified, the portable tank has no bot-
tom openings or three effective means
of closure; or
(
3
) When no bottom openings are au-
thorized, the alternative portable tank
must not have bottom openings.
(vi) Except when an organic peroxide
is authorized under § 173.225(g), if a haz-
ardous material is not assigned a port-
able tank ‘‘T’’ Code, the hazardous ma-
terial may not be transported in a
portable tank unless approved by the
Associate Administrator.
(8)
‘‘TP’’ codes.
(i) These provisions
apply to the transportation of haz-
ardous materials in IM and UN Speci-
fication portable tanks. Portable tank
special provisions are assigned to cer-
tain hazardous materials to specify re-
quirements that are in addition to
those provided by the portable tank in-
structions or the requirements in part
178 of this subchapter. Portable tank
special provisions are designated with
the abbreviation TP (tank provision)
and are assigned to specific hazardous
materials in Column (7) of the § 172.101
Table.
(ii) The following is a list of the port-
able tank special provisions:
Code/Special Provisions
TP1
The maximum degree of filling must
not exceed the degree of filling determined
by the following:
Degree of filling
=
+
−
(
)
⎛
⎝⎜
⎞
⎠⎟
97
1
α
t
t
r
f
.
Where:
t
r
is the maximum mean bulk temperature
during transport, and t
f
is the tempera-
ture in degrees celsius of the liquid dur-
ing filling.
TP2
a. The maximum degree of filling
must not exceed the degree of filling deter-
mined by the following:
Degree of filling
=
+
−
(
)
⎛
⎝⎜
⎞
⎠⎟
95
1
α
t
t
r
f
.
Where:
t
r
is the maximum mean bulk temperature
during transport,
t
f
is the temperature in degrees celsius of the
liquid during filling, and
a
is the mean coefficient of cubical expan-
sion of the liquid between the mean tem-
perature of the liquid during filling (t
f
)
and the maximum mean bulk tempera-
ture during transportation (t
r
) both in
degrees celsius.
b. For liquids transported under ambient
conditions
a
may be calculated using the for-
mula:
α =
−
d
d
d
15
50
50
35
Where:
d
15
and d
50
are the densities (in units of mass
per unit volume) of the liquid at 15
°
C (59
°
F) and 50
°
C (122
°
F), respectively.
TP3
The maximum degree of filling (in %)
for solids transported above their melting
points and for elevated temperature liquids
shall be determined by the following:
Degree of filling = 95
d
d
r
f
⎛
⎝⎜
⎞
⎠⎟
.
Where: d
f
and d
r
are the mean densities of the
liquid at the mean temperature of the liquid
during filling and the maximum mean bulk
temperature during transport respectively.
TP4
The maximum degree of filling for
portable tanks must not exceed 90%.
TP5
For a portable tank used for the
transport of flammable refrigerated liquefied
gases or refrigerated liquefied oxygen, the
maximum rate at which the portable tank
may be filled must not exceed the liquid flow
capacity of the primary pressure relief sys-
tem rated at a pressure not exceeding 120
percent of the portable tank’s design pres-
sure. For portable tanks used for the trans-
port of refrigerated liquefied helium and re-
frigerated liquefied atmospheric gas (except
oxygen), the maximum rate at which the
tank is filled must not exceed the liquid flow
capacity of the pressure relief device rated
at 130 percent of the portable tank’s design
pressure. Except for a portable tank con-
taining refrigerated liquefied helium, a port-
able tank shall have an outage of at least
two percent below the inlet of the pressure
relief device or pressure control valve, under
VerDate Sep<11>2014
16:41 Oct 31, 2018
Jkt 244226
PO 00000
Frm 00381
Fmt 8010
Sfmt 8010
Q:\49\49V2.TXT
PC31
EN21JN01.000</MATH>
EN21JN01.001</MATH>
EN21JN01.009</MATH>
ER14JN05.003</MATH>