Technical Guidance for Shipping Bulk Liquids

T Codes for Liquid Tanks

T Code	Minimum Shell Thickness Reference Steel	Relief Provision	Outlet Provision	Minimum Test Pressure (bar)
T1	6mm	SRV	2 Shut Off Devices	1.5
T2	6mm	SRV	3 Shut Off Devices	1.5
T3	6mm	SRV	2 Shut Off Devices	2.65
T4	6mm	SRV	3 Shut Off Devices	2.65
T5	6mm	SRV + Rupture Disc + Check Gauge	Prohibited	2.65
T6	6mm	SRV	2 Shut Off Devices	4
T7	6mm	SRV	3 Shut Off Devices	4
T8	6mm	SRV	Prohibited	4
T9	6mm	SRV	Prohibited	4
T10	6mm	SRV + Rupture Disc + Check Gauge	Prohibited	4
T11	6mm	SRV	3 Shut Off Devices	6
T12	6mm	SRV + Rupture Disc + Check Gauge	3 Shut Off Devices	6
T13	6mm	SRV	Prohibited	6
T14	6mm	SRV + Rupture Disc + Check Gauge	Prohibited	6
T15	6mm	SRV	3 Shut Off Devices	10
T16	6mm	SRV + Rupture Disc + Check Gauge	3 Shut Off Devices	10
T17	6mm	SRV + Rupture Disc + Check Gauge	3 Shut Off Devices	10
T18	6mm	SRV + Rupture Disc + Check Gauge	3 Shut Off Devices	10
T19	6mm	SRV + Rupture Disc + Check Gauge	Prohibited	10
T20	8mm	SRV + Rupture Disc + Check Gauge	Prohibited	10
T21	10mm	SRV	Prohibited	10
T22	10mm	SRV + Rupture Disc + Check Gauge	Prohibited	10

Specific Gravity

What is Specific Gravity?

The term specific gravity, symbolized sp gr, refers to the ratio of the density of a liquid (or a solid) to the density of water at 4 degrees Celcius.

Unless a Baffle Tank is utilised it is recommended that for both Hazardous (Mandatory) and Non-Hazardous (not Mandatory) be loaded to less than 20% fill or greater than 80% fill. The actual level of fill above 80% is designated by the maximum gross mass of the tank container or the maximum permitted mass of the tank throughout its transit whichever is the least.

Irrespective of the above the tank container may not be filled above the degree of filling designated in IMDG 4.2.1.9. (this is the text which designates the degree of filling required taking in to account thermal expansion)

Also in all cases when loading any Tank Container, sufficient allowance must be made for the expansion of the product. This acknowledges the fact that during transportation the product will experience a range of ambient temperatures. Regulations allow for a maximum 97% fill in some cases however, in line with many operators policies, it is suggested 95% filling ratio should be adopted. Tank Size Choice (in the table below is an “At a Glance” aid only) – If a Baffle tank is utilized the 80% minimum fill rate no longer applies.

	21 Tonnes	21 Tonnes	22.5 Tonnes	22.5 Tonnes	24 Tonnes	24 Tonnes
	Max 95% Fill	Max 80% Fill	Max 95% Fill	Max 80% Fill	Max 95% Fill	Max 80% Fill
Size of Tank Required	sp gr,	sp gr,	sp gr,	sp gr,	sp gr,	sp gr,
14000 Litre	1.58	1.88	1.69	2.00	1.80	2.14
15000 Litre	1.47	1.75	1.53	1.81	1.68	2.00
17500 Litre	1.26	1.50	1.35	1.61	1.44	1.71
19000 Litre	1.16	1.38	1.25	1.48	1.33	1.58
20000 Litre	1.105	1.31	1.18	1.41	1.26	1.50
21000 Litre	1.05	1.25	1.13	1.34	1.20	1.43
23000 Litre	0.96	1.14	1.03	1.22	1.10	1.30
24000 Litre	0.92	1.09	0.99	1.17	1.05	1.25
25000 Litre	0.88	1.05	0.95	1.12	1.01	1.20
26000 Litre	0.85	1.01	0.91	1.08	0.97	1.15

Comparison: Tank Containers vs Drums

Safe Method of Transporting Drums in a 20Ft ISO Container
vs.
Safe Method of Transporting Bulk Liquids in a 20Ft ISO Tank Container

Comparison: Tank Containers vs Flexitanks

There are a number of misconceptions held by some shippers when considering the use of Flexitanks that should be challenged and shippers should be encouraged to check these out for their own benefit.

“Bags are cheaper” That is often no longer the case and shippers should obtain quotes from Tank Operators to check for themselves.
“Bags are safe for the environment” Please ensure that your operator is providing the full service as detailed in their own Industry code of practice. Tank Containers have a proven low carbon footprint.
“Are you obtaining the same payload that you are in a Tank Container?”
“Is my cargo safe?” UK P&I Club Loss Prevention Bulletin