CFR

56.04-2—Piping classification according to service.

The designation of classes according to service is found in Table 56.04-2.

Table 56.04-2—Pressure Piping Classification

Service	Class 1	Pressure (p.s.i.g.)		Temp. (°F)
Class B and C poisons 2	I	any	and	0 and above.
	I-L	any	and	below 0.
	II	(3 )	(3 )	(3 )
	II-L	(3 )	(3 )	(3 )
Gases and vapors 2	I	above 150	or	above 650.
	I-L	above 150	and	below 0.
	II	150 and below	and	0 to 650.
	II-L	150 and below	and	below 0.
Liquefied flammable gases 2	I	above 150	and	0 and above. 1
	I-L	above 150	and	below 0.
	II	150 and below	and	0 and above.
	II-L	150 and below	and	below 0.
Molten sulphur	I	above 225	or	above 330.
	II	225 and below	and	330 and below.
Cargo liquids Grades A through D 2	I	above 225	or	above 150.
	I-L	above 225	and	below 0.
	II	225 and below	and	0 to 150.
	II-L	225 and below	and	below 0.
Cargo liquids Grade E	I	above 225	or	above 400.
	I-L	above 225	and	below 0.
	II	225 and below	and	0 to 400.
	II-L	225 and below	and	below 0.
Water	I	above 225	or	above 350.
	II	225 and below	and	350 and below.
Fuels (Bunker, diesel, gasoline, etc.)	I	above 150	or	above 150.
	II	150 and below	and	150 and below.
Lubricating oil	I	above 225	or	above 400.
	II	225 and below	and	400 and below.
Asphalt	I	above 225	or	above 400.
	II	225 and below	and	400 and below.
Heat transfer oil	I	above 225	or	above 400.
	II	225 and below	and	400 and below.
Code of Federal Regulations 176
Hydraulic fluid	I	above 225	or	above 400.
	II	225 and below	and	400 and below.

Flammable or combustible dangerous cargoes.	Refer to specific requirements of part 40 of this chapter .
Other dangerous cargoes.	Refer to specific requirements of part 98 of this chapter .
1 Where doubt exists as to proper classification, refer to the Commandant for resolution.
2 For definitions, see 46 CFR parts 30, 151, and 154 . Note that the category “B and C” poisons is not used in the rules applying to self-propelled vessels (46 CFR part 153 ).
3 Not permitted except inside cargo tanks approved for Class B and C poisons.

[CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by CGD 73-254, 40 FR 40164, Sept. 2, 1975; CGD 73-96, 42 FR 49024, Sept. 26, 1977]

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