DEAS 936:2019  
ICS 75.160.30  
 
© EAC 2019                                                                                                                              First Edition 2019 
 DRAFT EAST AFRICAN STANDARD  
Handling, storage and distribution of liquefied petroleum gas in 
domestic, commercial, and industrial installations — Code of practice  —
Transportation of LPG in bulk by road, rail and sea  
EAST AFRICAN COMMUNITY  
 
 
 
 
 
  
 DEAS  936:2019 
ii © EAC 2019  – All rights reserved  
 Copyright  notice  
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 DEAS 936:2019 
© EAC 2019  – All rights reserved  iii 
 Foreword  
Development of the East African Standards has been necessitated by the need for harmonizing requirements 
governing quality of products and services in the East African Community. It is envisaged that through 
harmonized standardization, trade barriers that are encountered when goods and services are exchanged 
within the Community will be removed.  
The Community has established an East African Standards  Committee  (EASC)  mandated to develop and 
issue East African Standards  (EAS) . The Committee is composed of representatives of the National 
Standards Bodies in Partner States, together with the representatives from the public and private sector 
organization s in the community .  
East African Standards are developed through  Technical Committees that are representative of key 
stakeholders including government, academia, consumer groups, private sector and other interested parties. 
Draft East African Standards ar e circulated to stakeholders through the National Standards Bodies in the 
Partner States. The comments received are discussed and incorporated before finalization of standards, in 
accordance with the Principles and procedures for development of East Africa n Standards.  
East African Standards are subject to review, to keep pace with technological advances. Users of the East 
African Standards are therefore expected to ensure that they always have the latest versions of the standards 
they are implementing .  
The committee responsible for this document is Technical Committee EASC /TC 038, Liquefied Petroleum and 
Natural Gas Equipment and Accessories .  
Attention is drawn to the possibility that some of the elements of this document may be subject of patent 
rights. EAC shall not be held responsible for identifying any or all such patent rights.  
 
 DRAFT EAST AFRICAN STANDARD  DEAS 936:2019 
 
© EAC 201 8 – All rights reserved  1 
 Handling, storage and distribution of liquefied petroleum gas in 
domestic, commercial, and industrial installations — Code of practice — 
Part 2: Transportation of LPG in bu lk by road, rail and sea  
1 Scope  and field of application  
1.1 This draft East African Standard outlines  the code of practice to be followed while transporting Liquefied 
petroleum gas in bulk by road, rail and sea . 
1.2 This standard does not cover transport ation of LPG in cylinders.  
2 Normative references   
The following documents are referred to in the text in such a way that some or all of their content constitutes 
requirements of this document. For dated references, only the edition cited applies. For unda ted references, 
the latest edition of the referenced document (including any amendments) applies.  
ISO 2928,  Rubber hoses and hose assemblies for liquefied petroleum gas (LPG) in the liquid or gaseous 
phase and natural gas up to 25 bar (2,5 MPa) -- Specific ation  
IEC 60079;  Part 1-25 
EAS 901 , Inspection and testing of Liquefied Petroleum Gas (LPG) road tankers  
EAS 902 , Bulk Liquefied Petroleum Gas (LPG) road tankers — Assembling — Requirements  
EAS 903 , Road tankers — Welded steel tanks for Liquefied Petroleum  Gas (LPG) — Design and manufacture  
IEC 60079 -10, Explosive atmospheres — Part 10: Classification of areas - Explosive gas atmospheres  
IEC 60079 -14, Explosive atmospheres — Part 14: Electrical installations design, selection and erection  
IEC 60079 -17, Explosive atmospheres — Part 17: Electrical installations inspection and maintenance  
ASME B31, Piping and piping systems  
BS 3351, Piping systems for petroleum refineries and petrochemical plants  
BS 3602, Specification for steel pipes and tubes for pressure pu rposes: carbon and carbon manganese steel 
with specified elevated temperature properties  
BS 4089, Rubber hose and hose assemblies for liquefied petroleum gas lines  
IP 250, Petroleum measurement tables based on a reference temperature of 20 ºC  
ASTM -IP, 
ISO 3874, Series 1 freight containers — Handling and securing   
2 © EAC 2019  – All rights reserved  
 International Maritime Organization (IMO) code for the construction and equipment of ships  
NFPA section 59 regulation 4.5  
International Safety Guide for Oil Tankers and Terminals) (ISGOTT) safety gu idelines  
3 Terms and definitions   
For the purposes of this document, the following  terms and definitions apply . 
3.1 
approved  
that which has been authorised by  the approving authority  
3.2 
approving authority  
within the scope of the relevant competent autho rity(ies) in the Partner States  
 
3.3  
filling ratio  
ratio of the mass of LPG introduced into a storage vessel to the mass of water (determined at, or corrected to, 
20 ˚C) that would fill the storage vessel  
NOTE  The term filling ratio applies when the filling of a liquefied gas into a storage vessel is controlled by the mass of 
the gas introduced.  
3.4 
LPG (Liquefied Petroleum Gas)  
pure propane, butane or a mixture of the  propane and butane  
3.5  
maximum working pressure  
the maximum internal pressure that is permi tted for a tank during service  
3.6  
semi -trailer  
a trailer having no front axle and designed  such  that at least 15 % of its tare is superimposed on and borne by 
a vehicle drawing the trailer  
 
3.7 
tank  
a pressure vessel designed for the conveyance of commercial propane, and where applicable complying with 
legislation in Partner States  
NOTE  A tank that is suitable for the conveyance of commercial propane may also be used to convey commercial 
butane and LPG mixtures.  
4 Bulk handling for movement by road  
LPG shall be  moved in tank trucks by road. These trucks  shall be  designed and manufactured by competent 
firms  and approved by competent authorities  . 
The trucks shall b e fitted with various devices in accordance with  EAS 901, EAS 902 and EAS 903 .  
© EAC 2019  – All rights reserved  3 
 4.1 Loading  and unloading facilities  
Each loading  and unloading  facility  shall consist of the following:  
a) Liquid and vapour lines shall be fitted with pressure gauge, isolati on valve and either an  excess flow valve  
or break away coupling or both.  
b) . In case of loading  with vapour compressor only , a  vapour return line with an isolation valve connected 
back to the storage vessel from which the loading compressor is drawing L PG.  The vapour line be 
protected with an excess flow valve  or break away coupling’  
c) suitable loading arm/flexible hoses as per ISO 2928  shall be provided at the end of filling and vapour 
return lines for connecting to the tank truck vessel.  
d) Where a pplicable weigh bridges of suitable capacity / mass flow meters shall be provided for custody 
transfer of product by mass otherwise LPG tanks should be filted with level gauges and valid calibration 
chart’  
 
e) An excess  flow valve or a break away coupling shall be provided in the vapour return line.  
Typical sketch es of loading  and unloading facilities  are as  shown in Annex C  and E respectively  
 
A typical sketch of.  
4.2 Safety precautions  
a) Transfer of LPG to or from a tank truck requires special attentio n as accidental movement of vehicle may 
cause rupture in the transfer  equipment.  
b) No source of ignition shall be allowed in the area where loading and unloading  of LPG  is carried out.  
c) Adequate firefighting extinguishers  and firefighting  system  where  applicable shall be available near the 
tank trucks during loading and unloading’  
d) After positioning the truck , proper earthing connections shall be provide d and shall be disconnected just 
before the release of the truck.  
e) plugs or caps, shall be crack ed open before removing to allow for release of trapped LPG and  to ensure 
that the valves are effectively sealed.  
f) Hoses shall be handled with care and inspected periodically as per ISO 2928.  
g) While disconnecting hoses/pipes, connections shall be lo osened only slightly at first to allow release of 
trapped pressure, if any.  
h)  personal protective equipment shall be be used while making or breaking the connections to avoid cold 
burns.  
i) Suitable g as leak detection system may be provided .  
j) The mas ter switch shall be put off immediately after parking the truck in position.  No electrical switch on 
the truck shall be turned " on" or " off" during the loading and unloading .  
k) No repairs shall be made on the truck while it is in the loading  and unloa ding area.   
4 © EAC 2019  – All rights reserved  
 l) New tank truck vessels or vessels received after repair shall be purged before loading ..  
m) It is recommended that the receiving vessel having a pressure of less than 1 bar should not be filled. 
Such vessel shall be checked for oxygen conte nt/explosive mixture and purged, if necessary.  
n) Venting and purging of LPG during loading and unloading  should not be carried out in an open 
atmosphere. It should be piped to a suitable flare system. Where such facility does not exist, vent pipes 
shall be provided to carry the LPG to a safe distance and released at a height not less than 3 m above 
the highest point of any building, shed or structure within 15  m radius. Snuffing steam facility may be 
provided for the vent line.  
o) loading and unloading  shall be stopped immediately in the event of; 
i) leakage occurring ; 
ii) A fire occurring in the vicinity  
iii) Lightning and thunder storm  
p) Loading and unloading operations shall not be undertake n in the darkness unless flame proof lights 
are provided.  
4.3 Procedures for operation  
4.3.1  Loading operations  
a) The following shall be check ed in a tank truck before accepting it for filling:  
— At least t wo safety valves are provided on the vessel.  
— Fixed tube gauge is provided.  
— Excess flow valve is provided.  
— Press ure gauge is provided.  
— Temperature gauge is provided.  
— Fire screen between cabin and vessel is provided.  
— 2 Nos. of 9 kg dry chemical powder  fire extinguishers are provided.  
—  Spark arrestors of approved quality are fitted.  
— No leakage in exhaust silencer pipe  exists.  
— Manufacturer's name plate with date of testing is fitted on the vessel.  
— Valid explosive licence is available.  
— Approved drawings of vessel are available.  
— Blind flanges/caps are provided on vessel.  
— Earthing cable is provided.  
— Bonding between vessel and chassis is satisfactory.   
© EAC 2019  – All rights reserved  5 
 — Bonding between flanges in manifold is satisfactory.  
— Excess flow valve and control valve are available on water drain line.  
— Bonding point is available.  
— Third party inspection/test certificates for vessel/fittings are available  and valid  
— Liquid / vapour line valves are in good condition.  
b) The truck  shall be moved to the loading bay/weigh bridge and  the tare weight of the empty tank truck  
recorded . 
c) Residual LPG pressure shall be Check ed and record ed using fitted devices.  
d) The truck shall be stopped on a leve lled ground and chock blocks place d at the front and rear wheels.  
e) the engine shall be s topped and all electrical equipment  shall be switch ed off. 
f) All persons shall leave the driver's cabin.  
g) Fire extinguishers shall be readily  available.  
h) bonding connections of the vehicle  shall be made  at specified point to the fixed grounding system.  
i) liquid line and vapour lines shall be c onnect ed with the loading point  
 Note: Hoses should not be passed under the loading/of floading truck). The valves  should be cracked  open on 
loading and vapour  return lines  and  inspect ion of  hoses and connections for leakage. Loading should 
start only when the system is leak free.  
j) the loading pump /compressor  shall be s tarted. 
k) The quantity loaded into the truck may be determined by ; 
i) Liquid level ; 
ii) Weighing ; and  
iii) Positive displacement meter . 
l) Liquid level may be determined by roto -gauge , magnetic  gauge or fixed liquid level gauge. Percentage 
volume to be filled should be pre-determined.  
m) Where weigh -bridge is used, it is necessary to determine the density of the product being loaded to avoid 
excess filling in terms of volume. The weigh bridge shall be periodically calibrated and stamped by 
relevant  Authorities  in Partne r States . 
n) Whether a gauging device is used or a weigh bridge is employed for filling operation, when   the liquid 
content is approximately within 5% of the safe filling level, the operator should be in a position to control 
the shut off valve and starts  to close the valve as the safe filling level approaches.  
o) When the filling operation is in progress, the pressure within the tank truck vessel should be observed to 
ensure that it does not approach the start -to-discharge pressure of the relief valve.  Filling rate may be 
regulated as required.  
p) The couplings may then be removed and plugs/caps replaced on the tank truck valves. Recheck for leaks 
from the plugs/caps shall be done.  In case of any leaks, they shall be rectified before commencement of 
transfer operations   
6 © EAC 2019  – All rights reserved  
 q)  All the operations shall be attended to by the driver and the loader at all times to actuate the 
stop button in the case of emergencies.  
r) The loadings shall not exceed the load axle limits stipulated in the EAC regulations  
4.3.2  Unlo ading operation  
Operations prescribed below  should be carried out.   
a) Liquid line and vapour line of the tank truck should be connected to the respective hoses fixed to the 
unloading point.  
b) Test the connections for leaks by slightly opening the valve s for pressurising. When satisfied, valves on 
the tank truck and the receiving vessel should be opened.  
c) Start the evacuation compressor..  
d) Ensure  that the pressure created within the delivering vessel does not reach or exceed the set pressure 
of the  relief valve.  
e) An authorised person of the company should supervise the unloading and loading  and respond 
immediately in the event of an emergency.  
f) After the liquid has been expelled, the vapour recovery operation should be started. Ensure  that the 
pressure of the delivering vessel is not below 1.5 bar.  
Operations prescribed  in 4.3.1(a) should now be carried out.  
4.3.3  Unloading at customers site 
For all bulk deliveries the customer shall provide an assistant for the driver during the discharging operations, 
or an assistant shall accompan y the driver.   
The following is a typical unloading procedure at the customer`s site:  
a) Properly position the bulk truck for unloading and stop engine.  The truck cab shall face the exit.  
b) Set the hand brake to  'on' position.  Place chocks at the wheels of the bulk truck to prevent it from 
moving.  Set brake interlock.  
c) Isolate truck electrics where necessary.  
d) Cordon off the area, put safety signages “LPG Unloading in Progress Keep Clear” and deploy fire 
extinguishers at convenient nearby location.  
e) Ensure there are no naked lights or work where sparks can be generated in the area.  
f) Ground or bond the bulk truck.  
g) Check quantity of LPG in the customer's storage tank and ensure adequate space is availab le to take 
product from the bulk truck.  
h) . 
Hook up the discharge hose from the bulk truck to the inlet of the storage tank. Also hook up the vapour return 
line if it is installed . Vapour return line can only be used where delivery is recorded by using a 
weighbridge ,level gauges and valid calibration chart .  
© EAC 2019  – All rights reserved  7 
 i) Take initial readings and open all the valves to the storage tank, leaving the truck valves closed.  Check 
for leaks . j) When the absence of any leak is confirmed, open the truck vapo ur valve follow ed by the 
liquid valve, restart the truck engine and begin discharge operations.  
k) Check flow through the delivery meter on bulk truck as well as from rotary gauge / magnetic gauge  on 
storage tank.  
l) Once the desired quantity or level is reached, stop the  pumping operations.  Shut off the truck engine.  
m) Isolate all valves.  
n) where applicable, d isconnect discharge and vapo ur hoses.  
o) Remove the grounding or earthing connections.  
p) Take the readings of level in the storage tank using rotary gauges /magne tic gauge  as well as quantity 
discharged from bulk truck.  Ensure the tank has not been overfilled.  In case of overfilling the driver shall 
secure the customers tank and call in  gas expert for emergency instruction . 
NOTE 4: Ensure  the tank has not been ov erfilled ,  
q) Inspect the area again, checking that the storage tank and bulk truck are leak -free. 
Remove the chocks from under the wheels of the bulk truck and open the barricade in the area  After 
discharging operation of bulk LPG is completed.  
Warning  unload ing the bulk truck shall not be done during lightning or rainstorm.  
The unloading operation shall be fully attended by the bulk truck driver and the customer's representative, when provided, 
at all times.  The driver shall stop the operation, if the driver needs to move away from the off -loading point, for any 
reason, unless accompanied by a fully trained assistant.  
 As with all bulk LPG transfers, the driver and the assistant shall wear protective clothing.  
The essential checklist instructions shall be posted on a sign  board  at the customer bulk LPG fill point.   
5  Bulk handling for movement by rail  
LPG is moved in tank wagons by the railways. These wagons shall be designed and manufactured by a 
competent firms and approved by competent authorities.  
5.1  Facilities  
5.1.1  Loading  
Each loading point shall consist of the following:  
a) A filling line with excess flow check valve and an isolation valve.  
b) A vapour line with a check valve and an isolation valve to be connected back to the vessel from which  
LPG is drawn.  
c) Flexible hoses with break -away couplings to be connected with the filling and the vapour return lines.  
d) A check valve to be provided at the end of flexible hose with the filling line.  
A typical sketch of loading facility is shown in Ann ex C.   
8 © EAC 2019  – All rights reserved  
 5.1.2  Unloading  
Unloading of LPG from tank wagons shall be done with the help of compressor.  
NOTE  The compressor is used to create a differential pressure between the receiving and discharging 
vessels by withdrawing vapo urs from the receiving vessel  and forcing it at high pressure into the discharging 
vessel thereby establishing a smooth flow.  
The content of tank wagons can be ascertained by weighing on weighbridge before and after emptying or, 
alternatively, the quantity can be determined based on wagon gauge readings and differential in storage tank 
gauge readings before and after receipt, wherever physical weighing is not possible.  
5.2  Safety precautions  
a) the locomotive shall not be allow ed to come on the weigh bridge d ue to its capacity limit ation. Sufficient 
number of dummy wagons may be used to avoid loco motive  coming closer to the gantry.  
b) In the event of a leak:  
i) the loading pump /compressor shall be stopped . 
ii) the movement of loco motive  on the adjoining rails  shall be stopped . 
iii) all internal combustion engines that may be running in the nearby area  shall be s witch ed off. 
iv) hot work s, if any, in the within the facility  shall be s top. 
v) all the vehicular traffic in the vicinity  shall be s top. 
vi) In the event of a leak, water moni tors shall be s tarted to form a blanket covering the leak and the 
wagon/piping from which LPG is coming out.  
vii) Emergency response team shall be put on alert and where available the fire engine with crew shall 
be put on standby  
viii) All the maintenance  jobs in the area  shall be s top. 
ix) The system shall be d epressurise d before attending to the leak.  
x) if the leak is from wagon , immediate steps shall be taken to decant the wagon.  
xi) the area  shall be cleared  of all the people except those who are requ ired to meet the emergency 
situation.  
xii) power supply in the area where leak is detected  shall be cut off. 
c) The first operation after positioning the wagon shall be to provide for proper earthing. Earthing shall be 
disconnected just before the release of the wagon.    
d) For connecting and disconnecting hoses, only non-sparking type of tools  shall be .  
e) After the wagons are placed on weigh bridge and before the loco motive  is detached, the hand brakes on 
each and every wagon shall be applied.  
f) Before the wagons are moved from the weigh bridge, brakes on all the wagons  shall be release d. 
g) Only footwear made from conductive rubber shall be used .  
© EAC 2019  – All rights reserved  9 
 h) the lower portion of flapper bridge at wagon side shall be  fitted with rubber or wooden padding  or any 
other recommended material .  
i)  The coir matting/rubber sheet shall be  spread on the platform.  
j) Ensure that electrical continuity of the system is intact.  
k) all fittings on the wagons shall be physically checked.  
l) Hoses shall be hydraulically tested  at least twice a year (six monthly).  
m) Excess flow check valve will stop the flow of LPG in case the flow is in excess due to accidental rupture of 
hoses etc. The isolation valve at grade level  shall be closed .  
n) During the loading/unloading, the oper ator shall be present near the wagons.  
o) During unloading, after the liquid transfer is over, the wagon pressure shall not be reduced below 1.5 bar  
5.3 Operating procedures  
5.3.1  Loading operation  
Place the wagon on weigh -bridge ensuring  that all the fou r wheels are properly accommodated on the 
platform. Engage hand brakes and put chocks. Check the residual LPG pressure in the wagon.  
move the locomotive away  from the weighbridge  and exhibit safety signs at suitable distance away from 
the wagons on both en ds.  
Switch off the locomotive  engine, if it is parked nearby.  
Note down the wagon numbers and placement time.  
Take loading advice.  
Note the time of receipt of advice.  
Connect earthing lugs to the wagons.  
Lower the flapper bridge slowly on the wagon.  
Open  the lid of the wagon.  
Take the tare weight reading and set the pointer of the scale to zero. Compare this with the marked tare 
weight on the wagon.  
Connect the filling hose and vapour return line hose to the wagon. Ensure that the flare connection valves 
are closed.  
Ensure that the header is charged with LPG and the bulk loading pump is running.  
Open the tanker filling line valve and vapour return line valve.  
Open the LPG isolation valve, located near the weigh scale.  
Check the system for leaks.  
Open the v alve on the vapour return line. Slowly open the valve on the filling line. Increase the valve 
opening and gradually open the valve fully.   
10 © EAC 2019  – All rights reserved  
  Gradually  open the  throttle valve on return line.  
Keep a check on the weigh scale readings. As soon as it shows the r equired weight of LPG to be filled, 
stop the compressor/pump and close the LPG isolation valve near the weigh scale.  
Close the wagon filling and vapour return lines valves and also valves on filling and vapour return lines at 
the loading point.  
Recheck fin al weight and record it. ensure that final gross weight does  not exceed the permissible axle 
load of the wagon.  
Open the valve on flare line connection to both feed line and vapour return line. Thus, the hoses are 
depressurised. Then, close the flare line connection valves.  
Disconnect the filling and vapour return line hose connections from the wagon.  Replace and tighten the 
plugs on filling and vapour return lines.  
Close the top cover of the wagon and seal it properly. Remove earthing connections.  
Prepar e the gate pass.  
Release the hand brake of the wagon.  
Release all the wagons on the loading points in the lot.  
5.3.2  Unloading operations  
Ascertain that the liquid discharge valve and the vapour valve within the tank wagon cover are in the 
closed position.  
Open the port covers in the side of the dome shell, if they exist. Unscrew the plugs in the outlets of the 
vapour valve and the liquid valves using a box wrench. This shall be done slowly.  
If there is any sound of escapi ng vapour or if there seems to be pressure behind the plugs, the pressure 
shall be allowed to relieve itself past the threads before the plugs are entirely disengaged.  
If the vapour discharge continues or if there is evidence of a liquid discharge, the valves should be 
retightened.  
With th e plugs removed, screw pipe nipples into the outlets of the valves after first having applied a 
modest quantity of sealant to the male threads, keeping the sealant away from the end of the thread. 
Tighten nipples with a pipe wrench.  
Connect the two liquid transfer unloading swing arms or hoses to the nipples attached to the liquid 
discharge valves. Connect the vapour or equalizing swing arm or hose to the nipple attached to the 
vapour valve. In most cases, these connections should  be made by means of either  a ground joint 
union or a hose coupling.  
In the event, a ground joint union is used, no gasket will be required. If a hose coupling is employed, 
ensure that the appropriate gasket is in place. Make sure th at they are secured tightly by appropriate 
means.   
After the vapour and liquid hoses have been connected and before any valve is opened, the valves on the 
tank wagon shall be  crack ed open in order to apply pressure to the hoses as a test for leaks.  
If any leak appears, the valve shall be immediately clo sed and corrective measures applied.  
Recheck the lines and connections to ensure  that they are connected correctly.   
© EAC 2019  – All rights reserved  11 
 After the liquid and vapour lines have been secured and tested, both liquid reduction valves shall be 
opened slowly and completely. Then, open all other valves in the liquid line working from the tank 
wagon to the storage tank.  
Open the storage tank filling valve slowly, if the tank wagon pressure is in excess of the storage tank 
pressure otherwise  the tank wagon excess flow check valves ma y get closed.  
If the tank wagon pressure is higher than that in the storage tank, do not open the valves in vapour line or 
operate the compressor. When the rate of liquid flow drops to an unsatisfactory level with the storage 
tank filling valve wide open,  open the vapour valves between the tank wagon and the storage tank.  
At this point, ensure  that the control valves at the compressor are in a position which allow the 
compressor to draw vapours from the storage tank and force it into the tank wagon, then start the 
compressor.  
When the tank wagon is held at a pressure of 2.0 to 2.5 bar above the storage tank pressure, the tank 
wagon shall be emptied into the storage vessel.  
A flow of gas instead of liquid through the sight -flow glass in the unloading line  indicates that the wagon is 
empty of liquid. Recheck this by opening the sample valve in the tank wagon dome.  
When the tank wagon is emptied of all liquid, stop the compressor and close the liquid valves beginning 
at the storage tank and progressing to t he tank wagon.  
If the facilities are arranged such  that vapours may be removed from the tank wagon, the pipeline at the 
compressor should be arranged such  that the compressor will draw vapour from the tank wagon and 
force it into the storage tank. The seq uence of piping line -up during unloading liquid LPG and vapour 
LPG is shown in Annex B.  
In this operation, the vapour should be discharged below the surface of the liquid in the storage tank to 
hasten the liquefaction and, in turn, help prevent excessive pressure in the storage tank.  
Restart the compressor and when the tank wagon pressure is reduced to about 1.5 - 2.0 bar, stop the 
compressor and close all the valves in the vapour line.  
After bleeding off the pressure in the hoses, disconnect both the li quid and vapour lines. Replace all the 
plugs in the tank wagon valves and the unloading fittings.  
Recheck sample valve, gauging device and thermometer well to determine that they have been returned 
to their original condition and are closed tight. Lower t he dome cover carefully and lock it in place 
with the locking pin or secure by appropriate means.  
Remove bonding/ earthing connections.  
Reverse or remove and replace the "Flammable" placard with "Dangerous - Empty" placard, if applicable.  
Remove the "Sto p - Tank Wagon Connected" sign and wheel blocks ( chocks).  
Any defect observed in the tank wagon shall be noted on the appropriate forms and routed in accordance 
with acceptable procedure.  
 Notify the railway  operator  in writing about release of wagon and  ensure that it is removed from the 
siding promptly.  
Gauge the storage tanks, within the plant, which have received the LPG to determine that the liquid level 
is appropriate.  
In the event of LPG received on weight basis, the tank wagon may require weighi ng following the 
completion of the unloading operation.   
12 © EAC 2019  – All rights reserved  
 5.4 Degassing of sick/leaky tank wagons  
5.4.1   Recommended procedure  
In the degassing system recommended for LPG wagons, vacuum cycle purging technique shall be followed as 
outlined below:  
1) Vessel  shall be evacuated repeatedly by a vacuum pump.  
2) Vapour shall be discharged through high rise vent, keeping the steam on.  
3) Maximum possible vapours shall be sucked out in first step depending on the capacity of vacuum 
pump/compressor. Between the two vacuum cycles, nitrogen/inert gas shall be used for breaking the 
vacuum.  
4) Cycle shall  be repeated until the LPG concentration is found below the end point of LPG (for butane, 
it is 4% by volume when purging is done by nitrogen). Periodically, samples shall be drawn from 
suitable location and analysed for LPG concentration.  
5) The vessel shall be flushed with air to displace the nitrogen. Barrel shall be tested with explosive 
meter to ensure that hydrocarbon concentration is below 10  % of Low Explosive Li mit (LEL).  
5.4.2  Alternate procedure  
Alternately, wagons may be degassed by flaring, steaming or filling with water. However, it should be ensured 
that wagon is made water free after degassing.  
6  Bulk handling for movement by sea  
Transportation of LPG in bulk by marine tankers may be carried out under fully -pressurised, semi -pressurised 
(semi -refrigerated) or fully refrigerated at atmospheric pressure conditions.  
6.1 Pressurised ships  
The cargo is carried in a number of cylindrical pressure vessels (or ca rgo tanks) capable of withstanding the 
maximum pressure likely to be met in service (usually 17 bars).  
6.2  Semi -refrigerated ships  
The pressure of the cargo is reduced by lowering its temperature to about 0 ˚C by the process of refrigeration 
and tanks co ntaining the cargo need not be so strong as those of pressurised ships. The tanks are thermally 
insulated.  
6.3  Fully refrigerated ships  
The cargo is carried at atmospheric pressure and the cargo tanks are "box -shaped" as opposed to cylindrical/ 
spherical  in case of pressurised/semi -refrigerated tankers for better utilisation of the ship's space.  
Pressure ships usually range from very small capacity to excess of 2,000 M3. capacity. The capacity of semi -
refrigerated ships usually ranges from 1,000 to 15000M3. Fully -refrigerated tankers could be made larger and, 
lighter  for any given size .  
6.4 Cargo carrier design and construction  
Some of the factors to be taken into consideration, which affect the design and construction of ships carrying 
LPG, are as follow s:  
© EAC 2019  – All rights reserved  13 
 a) Types of cargo to be carried,  
b) Condition of the carriage (i.e. fully pressurised, semi -refrigerated or fully refrigerated),  
c) Type of trade, which in turn, determines  the degree of cargo handling flexibility required by the 
tanker,  
d) Terminal fac ilities available when loading or discharging the vessel,  
e) Cargo containment systems (IMO code identifies five different types),  
f) Materials of construction (Fully refrigerated LPG cargoes shall have tanks capable of withstanding 
temperatures down to -55 ˚C. Alloy steels such as fully killed fine grain carbon manganese steel, 
sometimes alloyed with 0.5  % Nickel are used.),  
g) Tank insulation (for refrigerated cargo),  
h) Tanker layout and safety features,  
i) Survival capability and tank location,  
As specif ied by IMO codes, LPG carriers are required to undergo five different types of survey and have the 
certificates of fitness issued or endorsed. The certificate of fitness signifies that a minimum standard of 
constructional safety has been achieved. In order  for a tanker to comply with code throughout its life time, it 
shall be subjected to re -inspection to maintain its validity in compliance with National Maritime  rules and 
regulations.  
6.5  Facilities in the tanker  
The cargo handling equipment in a tanker  may comprise of  the following : 
a) Cargo pumps (submersible and booster),  
b) Compressors,  
c) Condensers,  
d) Heat exchangers , 
e) Vapourisers,  
f) Cargo heaters.  
The deep well pump supplies liquid to the booster pump to send the product ashore. In pressurised  ship, liquid 
shall be  withdrawn by pressurising the tank through vapour compression from other tanks. All semi and fully -
refrigerated tankers shall be  provided with cargo heaters to enable the vessels to discharge into pressure 
storage ashore and a booste r pump if the discharge pressure is significantly above 9 bars. Each cargo tank 
shall be provided  with the following equipment:  
a) Two cargo pumps, one each on either side of the longitudinal bulk head.  
b) Liquid discharge line from the tank dome, connect ed to the main liquid line.  
c) All emergency pump trunk way.  
d) A liquid loading line connected to the main liquid line.   
14 © EAC 2019  – All rights reserved  
 e) Two liquid level indicating devices one on each side. These usually consist of a float attached to a self - 
winding tape which move s up and down, either on guide wires or inside a guide tube. The liquid level is 
read off the tape through a gas -tight window at the top of and outside the tank.  
f) Two sets of purge lines at the top and bottom of the tank. These are used to distribute in ert gas or vapour 
for gas -freeing or gassing -up of the cargo tanks.  
g) A vapour line for withdrawal of vapour to the compressor.  
h) Sample tubes.  
6.6 Safety devices  
a) At least two safety valves in each cargo tank,  
b) High and low level alarms,  
c) Overfi ll alarm. When actuated, this will shuttle main loading valve and sound an alarm.  
The design of the tankers with regard to provision of facilities, equipment, accessories and safety features 
shall be in accordance with the IMO requirements.  
The electrical equipment of all gas tankers are subject to the requirements of the Flag Administration, the 
Classification Society and of IMO. The certified safe electrical equipment found on gas tankers are;  
a)  Intrinsically safe;  
b) Flameproof;  
c) Pressurised or purge d; and  
d) Increased safety  
6.7  Transfer pipework  
The following facilities on transfer piping between terminal and shore tanks shall be provided:  
a) Remotely operated valves (ROVs ) at both the ends of transfer line. (Additional ROV may be provided  at 
critical locations along  the pipe line route.)  
b) Relief valves on liquid line to surge vessel with an audible alarm system connected to high safe venting 
system  
c) Physical protection against impact to vent/drain pipes  
d) Protection of pipeline against corro sion, particularly when the pipeline passes under public road way, 
which is likely to be water -logged  
e) Pipe work passing public road way shall be designed to acceptable public highway authority standard in 
terms of roadway axle weights  
f) Pipelines shall be provided with insulating flanges to avoid pickup of stray currents and possible sparking 
from the Jetty to the receipt terminal.  
6.8 Terminal facilities  
Transfer of LPG from ship to terminal and vice versa is accomplished using hoses or loading arms.  If terminal 
authorities supply the cargo transfer hoses, NFPA section 59 regulation 4.5  shall be followed and complied  
© EAC 2019  – All rights reserved  15 
 with. However, if the hoses are ship hoses, these should conf orm to section 5 of IMO (IGC). Provision of 
vapour return facility depends on economics, transfer rates, distance of jetty from storage tanks, product 
pressures and temperatures etc.  
In case of pressurised gas transfer, it is observed that the pumping rate falls off gradually due to back 
pressure of the shore tank. A suitable va pour recovery system or liquefaction of the gas from the receiving 
tank is recommended . 
6.9  Ancillary equipment  
6.9.1  The ancillary equipment include:  
a) Pipe work, valves, relief valves, rotating equipment (pumps, compressors), exchangers, instrumentatio n, 
gas detection systems etc.  
b) Transfer line inerting facilities such as inert gas generation combined with water base foam generator and 
pipeline pig system or water storage with corrosion inhibitor chemical dosing transfer and supply facilities.  
c) Nitrogen cylinders with attendant facilities for hose purging/testing and alternate supply to ROVs and 
other instruments.  
6.9.2  The following agents may be incorporated in terminal fire control system : 
a) Water;  
b) Foam;  or 
c) Dry chemical powder.  
6.10  Unloading operations  
It is essential that the ship and terminal operators are familiar with the basic characteristics of each other's 
facilities, are aware of the precise division of responsibilities and are able to communicate effectively during 
the time the y are together involved in the joint operation of cargo handling. It is important that the terminal 
operators are versed with the current International Safety Guide for Oil Tankers and Terminals (ISGOTT ) 
safety guidelines.  
6.11  Communication  
Reliable and effective communications, irrespective of whether they are directly between the tanker and the 
terminal or indirectly via third party, are pre - requisites of safe and efficient cargo operations before the tanker 
comes alongside and during the period of car go operations and until the tanker departs. Terminal 
communication shall be compatible with tanker's system.  
6.12 Pre-cargo transfer discussions  
Before any cargo transfer operation is commenced, it is imperative that the intended procedures are 
thoroughly  discussed and a meeting held between the responsible personnel from the tanker and the terminal.  
The purpose of the meeting is primarily to make both sides fully conversant with the characteristics of the 
tanker and shore cargo handling systems, the envi saged operational and safety procedures and requirements 
and the parameters to be adhered to during the transfer.  
The content of the meeting will depend on a wide variety of circumstances but the following broad outlines 
form the basis of such meetings:  
a) The names and roles of terminal and ship personnel who will be responsible for cargo transfer operations 
may be noted.   
16 © EAC 2019  – All rights reserved  
 b) The terminal representatives shall check that pre -arrival instructions to the ship on cargo, cargo 
disposition and cargo condition ing have been carried out. They shall also check that all necessary tanker 
equipment , inspection and tests have been performed.  
c) the tanker's officers shall ensure  that the relevant terminal equipment and inspection checks have been 
carried out satisfac torily.  
d) Terminal representatives and customs and/or independent surveyors, where necessary, will be informed 
of the cargo tank data e.g. temperature, pressure, whether free  of cargo, liquid heel or arrival dip, 
composition of tank vapour  and quantity of cargo on board.  
6.13 Ship/shore safety checklist  
Sample checklist for ship/shore safety is given in Annex G. 
6.14 Disconnection of hose/ unloading  arm 
On completion of unloading operation , the tanker discharge pipeline shall be purged to push liquid LP G to the 
receiving tank. Purging may be done by LPG vapour, inert gas or water as per the design of the system. 
However, before disconnecting hoses or unloading arm, it is to be ensured that there is no liquid LPG left 
between the tanker main valve and sho re isolation valve. LPG Product from this length of p ipeline is to be 
safely vented.  
6.15 Calculating the quantity of liquid on board  
Before commencement of tanker discharge operation, tank readings for temperature, pressure liquid levels 
etc. are jointly agreed by the shore and marine tanker representatives. The corrections applied to assess the 
quantity of cargo on board are:  
a) Trim correction — to make allowance for the liquid level indicating devices not centrally located.  
b) Shrinkage factor — for correction of volume at 20 ˚C  
c) Low sounding trim corrections to allow for the wedge shaped volume.  
Volume at 20  ºC = Corrected Volume X VRF 
Quantity at 20ºC = Volume at 20 ºC X Density at 20 ºC 
NOTE  VRF is ascertained by ASTM -IP Table - 54).  
© EAC 2019  – All rights reserved  17 
 Annex A  
(informative)  
LPG Storage Vessel  
 
 
 
 
18 © EAC 2019  – All rights reserved  
  
Annex B  
(informative)  
General Arrangement of LPG tank lorry  
 
 
 
 
© EAC 2019  – All rights reserved  19 
 Annex C:  
(informative)  
 
A typical LPG transfer system for filling tank truck/wagon)  
 
 
20 © EAC 2019  – All rights reserved  
  
Annex D:  
(informative)  
Safe filling of LPG vessel  
 
LPG has relatively high coefficient of expansion. If sufficient vapour space is not left in the vessel, pressure 
inside the vessel would shoot up rapidly once the vessel becomes liquid full . Hence care is exercised in 
limiting the filling of storage vessel to the filling density of LPG. The filling density is defined so as to leave a 
guaranteed free space of five percent at the reference temperature of 55ºC. As per static and mobile pressure  
vessels (unfired) Rules - 1981, the design pressure of a vessel shall not be less than the vapour pressure of 
the gas in the vessel at 55 ºC. 
The following information are required to work out the safe filling capacity of a storage vessel.  
a) Water capacity of the vessel (WC)  
b) Density of liquid LPG  
c) Filling density (FD)  
d) Ullage factor (U)
  
 
C at LPGof densityUWCC atLPGof densityU WCFD  
5555
 
a) Safe maximum quantity of LPG that can be filled by weight – FD x WC  
b) Safe maximum quantity of LPG at 15 ºC that can be fill ed by volume percent of water capacity  
C at LPGof DensityFD
15100
 
c) Safe maximum quantity of LPG at t ºC that can be filled by volume percent of water capacity . 
Ctat LPGof densityFD
100
 
 
VRFC as LPGof DensityFD

15100
 
 
Where,  
 
FD  is the filling density  
 
WC is the Water capacity in litres at 15 ºC may be taken as total weight of water in kg.  
 
VRF   is the Volume reduction factor for density of LPG at t ºC as per ASTM Table 54.  
  
© EAC 2019  – All rights reserved  21 
 Annex  E: 
(informative)  
Unloading operations using pressure differential method of liquid  transfer  
 
 
 
 
 
22 © EAC 2019  – All rights reserved  
  
Annex F:  
 (informative)  
Typical LPG tank wagon  
 
 
 
 
 
© EAC 2019  – All rights reserved  23 
 Annex  G 
(informative)  
 
Liquefied gas -cargo transfer check lis t 
(Items to be checked before cargo transfer begins)  
 
SHIP:_________________________________________DATE:______________  
 
PORT  &BERTH:_________________________________TIME:______________  
 
1. Has information on cargo and ship shore connection been supplied ?  
 
2. Is the agreed ship -shore communication system operative?  
 
3. Are fire  and other emergency procedures agreed ?  
 
4. Are local regulations being observed?  
 
5. Has safe access been provided and warning notices posted?  
 
6. Are moorings secure and agreement reached on the use of tension winches?  
 
7. Are emergency towing -off wires correctly positioned?  
 
8. Is the ship ready to mo ve under its own power?  
 
9. Are smoking restrictions in force and notices posted?  
 
10 Are naked light restrictions being observed?  
 
11 Are portable electrical equipment cables disconnected?  
 
12 Are all hand torches and portable R/T sets of approved type?  
 
13 Are ship's main transmitting aerials and radar switched off and earthed?  
 
14 Some doors and ports have to be closed are they actually shut?  
 
15 Are all air conditioning intakes correctly trimmed and window type units closed?  
 
16 Is the water main ready for immediate use?  
 
17 Is the water spray system ready for immediate use?  
 
18 Are dry powder and all other fire fighting appliances correctly positioned and ready for immediate use?  
 
19 Is necessary protective clothing available or being worn?  
 
20 Are void  spaces properly inerted?  
 
21 Is the required ventilation equipment in operation?  
 
22 Is the cargo system set for the operation?  
 
23 Are all remote control valves in working order?  
 
24 Are cargo tank relief valves correctly set and in good order?  
  
24 © EAC 2019  – All rights reserved  
 25 Are t he required cargo pumps  and compressors in good order ?  
 
26 Is reliquefaction or boil -off control equipment in good order ?  
 
27 Is gas detection equipment set for the cargo, calibrated and in good order?  
 
28 Are cargo system gauges and alarms correctly se t and in good order?  
 
29 Are scuppers plugged and suitable drip trays in position?  
 
30 Are cargo and bunker hoses in good condition and properly rigged, have certificates being checked?  
 
31 Are unused bunker connections blanked and bunker tank lids closed?  
 
32 Are unused cargo connections (including inert gas line) securely blanked?  
 
33 Are automatic shutdown systems working properly?  
 
34 Does shore know the closing rate of ship's automatic valve at operating temperature does ship have a 
similar details of shore system?  
 
35 Are all personnel (including supernumeraries and new arrivals) aware that cargo transfer is to begin ?  
 
36 Have all personnel been allocated emergency stations?  
 
37 Are non -essential personnel clear of the cargo area?  
 
38 Are those direct ly involved aware of the agreed cargo  transfer sequence ?  
 
 ============================================================================  
REMARKS :  
 
We have checked with each other the items on the above check list and have satisfied ourselves that the 
entries we have made are correct to the best of our knowledge.  
 
 
CHECKED BY______________________     _______________________  
     (For Ship)     (For Terminal)  
  
© EAC 2019  – All rights reserved  25 
 Annex  H 
(informative)  
Safety related properties  of LPG  
 
Parameter  
 Commercial propane  Commercial b utane  
Boiling Point, degrees centigrade at 1 
atmosphere  - 45 - 7 
Vapour pressure, absolute at 15 ˚C 7.3 2.4 
Limits of flammibility% vol.,H/C in Air  
 
Upper  
 
Lower   
 
10.0 
 
2.2  
 
9.0 
 
1.8 
 
Gas to liquid volume ratio at 15 0C  
  
255  
232 
Volumes flammable  mixture per unit 
volume of liquid  
 11591  12889  
Ignition temperature, ºC.  
 450-550 420-540 
Co-efficient of expansion fraction  / º C  
  
0.003   
0.002  
Coefficient of compressibility (liquid), 
fraction/kg.sq.cm  
 2x 10-4 2x 10-4 
Gas density, kg/m3 at 15 ºC at 1 
atmosphere  2.0 2.5 
Liquid density, kg/m3 at 15 ºC at 1 
atmosphere  510 580 
 
 
 
  
26 © EAC 2019  – All rights reserved  
 Bibliography  
[1] KS 1938 -2:2012, Handling, storage and distribution of liquefied petroleum gas in domestic, commercial, 
and industrial installations — Code of practice — Part 2: Transportation of LPG in bulk by road, rail and sea  
 
 DEAS    : 2018    
 
© EAC 2018  – All rights reserved