MV Seasong 201307/004 1

Marine Safety Investigation Unit

SAFETY INVESTIGATION REPORT

201307/004 REPORT NO.: 18/2014 July 2014

MT Seasong Serious injury to crew member

in position 36° 19.5’N 035° 11.8’E

06 July 2013

SUMMARY

On 06 July 2013, at about 1100,

the second engineer on board

the oil tanker Seasong

commenced the overhaul of one

of the boiler’s main steam

valves.

The second engineer loosened

each of the six bolts holding the

valve bridge to the valve body

and gradually lifted it to ensure

that any entrapped steam and

hot condensate is released

gradually and safely.

Seeing that the release of steam

had died down, the second

engineer moved closer to the

main steam valve to lift the

valve bridge clear from the

valve body.

Suddenly, hot water escaped

from the valve housing and

spilled over both legs of the

second engineer. As a result of

the spill, the second engineer

suffered burn injuries, which

required hospitalisation.

The safety investigation found

that the immediate cause of the

accident was the escape of

steam and hot condensate water

which had remained entrapped

in the system.

As a result of the conclusions

reached, two recommendations

have been made to the Company

to ensure increased awareness

on the dangers of hot

condensate and steam.

The Merchant Shipping (Accident and Incident Safety Investigation) Regulations, 2011 prescribe that the sole objective of marine safety investigations carried out in accordance with the regulations, including analysis, conclusions, and recommendations, which either result from them or are part of the process thereof, shall be the prevention of future marine accidents and incidents through the ascertainment of causes, contributing factors and circumstances.

Moreover, it is not the purpose of marine safety investigations carried out in accordance with these regulations to apportion blame or determine civil and criminal liabilities. NOTE

This report is not written with litigation in mind and pursuant to Regulation 13(7) of the Merchant Shipping (Accident and Incident Safety Investigation) Regulations, 2011, shall be inadmissible in any judicial proceedings whose purpose or one of whose purposes is to attribute or apportion liability or blame, unless, under prescribed conditions, a Court determines otherwise.

The report may therefore be misleading if used for purposes other than the promulgation of safety lessons.

© Copyright TM, 2014.

This document/publication (excluding the logos) may be re-used free of charge in any format or medium for education purposes. It may be only re-used accurately and not in a misleading context. The material must be acknowledged as TM copyright. The document/publication shall be cited and properly referenced. Where the MSIU would have identified any third party copyright, permission must be obtained from the copyright holders concerned.

MV Seasong

MV Seasong 201307/004 2

FACTUAL INFORMATION

Vessel

Seasong is a 57,162 gt oil tanker, owned by

Rose Navigation Limited and managed by

Thenamaris Ships Management Inc. of

Greece. The vessel was built by Hyundai

Heavy Industries Co. Ltd, Republic of Korea

in 2005 and is classed by American Bureau

of Shipping (ABS).

Seasong has a length overall of 244.0 m, a

moulded breadth of 42.0 m and a moulded

depth of 21.0 m. The vessel has a summer

draught of 14.9 m and summer deadweight

of 105,472 tonnes.

The vessel is a double hull tanker, fitted

with 14 cargo oil tanks. The cargo lines are

fitted with valves and are arranged in such a

way that the vessel can carry three grades of

cargoes segregated in different cargo oil

tanks.

Propulsive power is provided by a

6-cylinder, two-stroke Hyundai-B&W

6S60MC, slow speed direct drive diesel

engine, producing 11323 kW at 97 rpm.

This drives a single fixed pitch propeller,

reaching a speed of about 14.5 knots.

Crew

At the time of the accident, the vessel had a

crew of 24. All crew members were

Bulgarian and Filipino nationals. The

vessel’s manning was in excess of the

number specified in the Minimum Safe

Manning Certificate. All crew members

were appropriately certified for their

respective positions on board.

The Bulgarian second engineer had joined

the vessel at Savona, Italy, on 17 June 2013.

He had been at sea for about 13 years and

had served as second engineer for about five

years under the management of the same

Company.

Ship’s steam generating plant

The steam supply on board Seasong is used

for the heating of bunkers, cargo, and

domestic needs. The supply is provided by

a plant, which consists of two oil-fired,

Hyundai HMT-25 water tube boilers. The

vessel is also fitted with one economizer,

utilising the heat from the exhaust gases

generated by the main engine.

The steam demand in port is served by

operating either or both of the boilers. At

sea, the demand on the system can be met by

operating the economizer, either solely or in

combination with one of the boilers.

Each of the boilers is designed to produce

25,000 kghr-1

steam at 18 kgcm-2

working

pressure. The boiler is of a rectangular type

construction, mainly incorporating the

furnace, steam and water drums connected

by generating tubes, membrane water wall

tubes and heated internal downcomer tubes

(Figure 1).

An oil-fired burner, located at the roof of the

membrane water wall construction furnace,

burns fuel to generate hot gases, which heat

the water as it rises in the steam-generating

tubes, producing steam in the steam drum.

The steam delivery lines between the two

boilers are connected and branch out to a

common line, leading to different services.

The delivery of steam from each boiler is

through two manually operated valves,

located at the top of the steam drum

designated as VIA (main steam valve) and

VIB. Valve VIB is a smaller valve used

during initial start up of the system with low

steam demands (Figure 2). Both valves are

of the non-return type, i.e. they prevent

steam and / or condensate water from back-

flowing to the steam drum.

MV Seasong 201307/004 3

Figure 1: Hyundai marine water tube boiler Adopted from boiler’s construction manual

After the steam delivery valves on each

boiler, a manually operated screw down

globe valve is fitted, designated as 48V

(Figure 2 and 3) on boiler no. 1 and valve

47V on boiler no. 21. In cases where only

one boiler is in operation (either due to low

steam demands or one of the boilers is on

stand-by mode), these valves are closed to

isolate the main delivery valves from the

1 This valve is not shown in Figure 2.

main delivery valves from the operating

boiler.

The water drums have built-in coils, which

enable the water to be heated by the other

boiler (supplied through the coils), even

when particular maintenance on any one of

the boiler is required to be carried out.

MV Seasong 201307/004 4

Figure 2: Boiler no. 2 indicating arrangement of

steam delivery valves

Figure 3: Side elevation of valve 48V

Narrative2

Seasong discharged a cargo of crude oil at

Sidi Kerir, Egypt on 03 July 2013 and sailed

out in ballast, bound for Ceyhan, Turkey to

load her next cargo. Due to the relatively

short distance to Ceyhan (approximately 400

2 Unless otherwise stated, all times are local.

nautical miles) and the loading date (which

was scheduled on 06 July 2013), the vessel

remained adrift several miles outside the

port as from 04 July 2013 at approximately

2330.

During the time the vessel remained adrift,

the steam demands were met by boiler no. 1,

which was operating at a working pressure

of between 5.6 bars and 8.8 bars.

Boiler no. 2 was on ‘stand-by’ mode, heated

up by steam from the other boiler and

maintaining a pressure of

3.3 bars. Since boiler no. 2 was not

generating steam, both delivery valves and

isolating valve 48V were closed.

On 05 July, at approximately 1700, the

second engineer observed water mist

forming over the insulation of the main

delivery valve VIA on boiler no. 2. It

seemed that the steam leakage was from the

valve’s gland, past the packing around the

valve spindle.

The second engineer informed the chief

engineer of the leakage. Isolating valve 48V

was tightened further and the steam leak

from the main valve was eliminated.

Nonetheless, the chief engineer decided to

cool down boiler no. 2 in order to overhaul

the leaking valve prior to the vessel’s arrival

at Ceyhan, where both boilers would then be

required during the cargo loading operation.

By 1730, the steam supply from boiler no. 1

to boiler no. 2 water drum was closed and

the latter boiler was left to cool down so that

maintenance could be started on the

following day. The chief and second

engineers left the engine control room at

approximately 1800. The engine-room was

switched to UMS, with all relevant

extension alarms being transferred to the

accommodation.

On the following morning, at about 0800,

the engineers returned to the engine-room

and proceeded to boiler no. 2. The pressure

MV Seasong 201307/004 5

Steam

delivery

Non-return valve disc

Valve bridge

Bolt holes

Steam drum

Valve

gland

Valve

packing

gauge on the steam drum read

0 kgcm-2

. No steam was seen escaping from

the vent valve. Zero pressure was also

confirmed on the remote control panel in the

engine control room. Based on the above

observations, the chief engineer considered

that the boiler had cooled down sufficiently

and that he may safely proceed with the

overhauling of the valve.

A chain block arrangement above the valve

was rigged to facilitate the lifting of the

valve bridge (Figure 4). However, the valve

was not overhauled at this stage since the

crew’s coffee break was due and a safety

meeting had to be held.

Figure 4: Arrangement rigged for remote lifting of

valve bridge

After the coffee break, the meeting was held

between the master, the chief mate, the chief

engineer, and the second engineer. The

safety issues for the intended work were

discussed in accordance with the Company’s

SMS procedures. The Company’s work

permit form for cold / pressurised system

was subsequently filled-in and signed by all

the meeting participants.

The work on the valve commenced at about

1100 by the second engineer under the

supervision of the chief engineer. In the

meantime, the other engine-room personnel

were carrying their normal duties. The

fourth engineer and the wiper were working

on the incinerator, the oiler sounding the

bunker tanks, whilst the third engineer was

working on the auxiliary engines.

Each of the six bolts holding the valve

bridge to the valve body were gradually

loosened up by about 12 mm. The valve

bridge was then lifted up (with the aid of the

chain block arrangement) by approximately

5 mm to 6 mm from the valve body (Figure

5). This approach was in accordance with

the agreed safety procedure prior to the full

removal of the valve bridge. It was intended

to ensure that no steam escaped / was

present and that the isolation valve (48V)

was indeed properly tightened.

Figure 5: Side elevation of main steam valve

MV Seasong 201307/004 6

When the valve bridge was lifted slightly, a

small trace of water mist was observed

coming out from the small gap between the

valve bridge and the valve body. However,

it soon died out. The insulation around the

valve body was subsequently removed and it

was verified again that there were no traces

of escaping steam.

Based on this, the chief engineer considered

that the isolation valve 48V was properly

tightened and boiler no. 2 was completely

isolated from boiler no. 1 and that it was

safe to lift the valve bridge completely clear

from the valve body.

The second engineer went back to the valve

to complete the work when at about 1115, a

splash of hot condensate water escaped

under pressure from the gap between the

valve bridge and valve body. The hot water

spilled over both the second engineer’s legs.

Figure 6: A reconstruction of the approximate

position of the second engineer next to the valve

when the hot water spillage happened

As a result of the water spill, the second

engineer sustained burn injuries and was

taken to the ship’s hospital for first-aid

treatment. The vessel’s managers were

notified of the accident by the master.

Subsequently, the chief engineer safely

completed the overhaul of the main steam

valve with the assistance of the third

engineer and the fitter. An internal

inspection after the removal of valve’s

bridge indicated that the valve body and the

one metre length of pipe up to the isolation

valve 48V were full of hot condensate water.

The vessel arrived at Ceyhan and was safely

moored alongside on 06 July at 2000. The

second engineer was transferred to hospital

to receive specialised medical care.

Safety management system

Safety procedures and standards for work on

boilers were addressed in Chapter 11,

Section 13 of the Company’s SMS manuals.

The sections included safety precautions for

work on boilers and steam lines, entering the

boilers, and closing of boiler drums after

opening-up for inspection.

The safety precautions for work on boilers

and steam lines specified the closing of

valves to isolate the working area, having

two-valve separation between live system

and place of work where possible, ensuring

awareness by all personnel of possible

leakage and that all these precautions remain

in force when work resumes after a break.

The handling of hot piping and pressurised

systems were separately addressed in

Chapter 11, Section 19 of the SMS manuals.

The safety procedures for the handling of

hot piping systems cautioned that any escape

of steam, hot water, etc. or accidental

contact with the naked skin can cause severe

injuries (burns, etc.). Reference was also

made to precautionary measures such as

pipe isolation and cooling down, draining

the pipe and associated control means

(manometers, thermometers, etc.) from any

MV Seasong 201307/004 7

content (oil, steam and / or water), utilising

personal protective equipment and

consulting makers’ manuals and / or ship’s

drawings.

The handling of pressurised systems was

also identified as involving similar risks of

hot piping and was addressed separately in

relevant Cold Work Permit Form SQ/43.

This Form was filled before the specific

maintenance work was initiated. It was

countersigned by the master, the chief mate,

and the chief and second engineers. The

Form outlined various preparations and

checks that had to be carried out.

As there were no records of similar work

carried out previously on board with the

steam plant in operating condition, the chief

engineer attempted to adapt the Form to the

specific job on the boiler valve, inter-alia,

by addressing the following safety

procedures:

boiler steam pressure to drop down to

0 kgcm-2

;

the valve bridge had to be cracked and

only from a remote position, before

the complete removal of the bolts; and

the damaged valve had to be isolated

from the rest of the live steam line.

The chief engineer cautioned that the

equipment was expected to contain hot

condensate water when opened. The Form

also referred to personal protective

equipment that had to be worn, i.e. a safety

helmet, safety shoes, safety goggles, boiler

suit, leather gloves and ear protections.

However, neither heat resistant boiler suits

nor protective aprons were included in the

list.

ANALYSIS

Aim

The purpose of a marine safety investigation

is to determine the circumstances and safety

factors of the accident as a basis for making

recommendations, and to prevent further

marine casualties or incidents from

occurring in the future.

Cause of hot water escape

The steam leakage from the main valve of

boiler no. 2, as initially observed by the

second engineer, suggested that apart from

defective packing of this valve, pressurised

steam was also leaking through the isolation

valve 48V. The steam was originating from

boiler no. 1, which was in operation at the

time (Figure 7). In fact, the leakage was

stopped by tightening valve 48V and boiler

no. 2 was left to cool down.

The pressurised steam trapped within the

approximately one metre length of pipe

section between the main valve and the

isolation valve 48V would have gradually

condensed to water during the cooling down

of the boiler, although it would have

remained hot (at a relatively high

temperature) by residual heat and the steam

reaching the other side of valve 48V from

boiler no. 1.

Masses of hot condensate would contain

relatively high levels of enthalpy. With the

pressure further reduced, the latent energy

would have vaporised the hot condensate. The

(large volumes) of generated steam would also

tend to travel in the direction of the lower

pressure, (even if this would have been slight),

such as where the valve bridge was lifted from

the valve body.

Whilst the chief engineer confirmed zero

pressure in the steam drum, there were no

available means to verify whether there was

any residual pressure within the isolated

pipe section between the main valve and

MV Seasong 201307/004 8

Bo

iler

no

. 2

B

oil

er n

o.

1

Figure 7: Schematic drawing of the boilers and steam lines

MV Seasong 201307/004 9

valve 48V. Furthermore, the presence and

status of any hot condensate water could not

be verified as the pipe section was not

provided with a drain valve.

It should also be noted that if hot condensate

was trapped at relatively high temperature, the

thermal energy could change into pressure

energy during the cooling down period,

ejecting the steam / condensate through an exit

point, such as the one provided as a result of

the removal of the valve bridge (Figure 8). It

must be stressed that this could only happen if

the means of drainage in the specific section

of pipeline were either inadequate or (as in

this case) not available.

Figure 8: Main steam valve indicating position of

valve bridge and the gap formed from the valve

body

The chief engineer focused his attention on

the tightness of the isolating valve 48V and

concluded that it was keeping well since no

further steam was observed after a waiting

time of about three to five minutes.

According to the chief engineer, the splash

of hot condensate water from the gap

between the valve bridge and the valve body

was sudden without any reason and at a time

when the second engineer had just only

approached the main valve and was standing

adjacent to it.

The safety investigation did not identify a

technical reason for the possible leakage of

the hot condensate water without some

intervention from the crew. It was therefore

not excluded that the valve bridge was

somehow lifted, most likely by the

(inadvertent) operation of the rigging

arrangement (Figure 4).

Protective clothing There was no doubt that the second

engineer, under the supervision of the chief

engineer, was cautious in his actions; he

slowly and partially removed the nuts that

held down the valve bridge to the valve

body. The valve bridge was only removed

when the crew members satisfied

themselves that there was no indication of

residual pressurised steam or hot condensate

water. However, it has to be stated that the

injuries sustained by the second engineer

confirmed that he was not wearing adequate

protective clothing.

Maintenance requirements/records

The PMS implemented on board Seasong is

in the form of AMOS computer software.

The crew members also keep files with hard

copies on board. The boilers’ manuals and

the Company’s planned maintenance system

implemented on board did not incorporate

any specific requirements or instructions

related to the inspection or overhauling of

this specific valve.

The chief engineer was not aware whether

the specific valve on either boiler had ever

been opened up before for overhauling and /

or the replacement of the packing.

Moreover, there were no records which

could give clear indications on the matter.

Risk assessment

The risk assessment followed on board is

based on computer software forms which

can also be accessed and reviewed by the

Company.

MV Seasong 201307/004 10

Company procedures establish that risk

levels between ‘0’ and ‘4’ were to be

considered as acceptable risk levels and the

ship would be able to proceed with the

specified work without the intervention of

the Company. For risk level ‘5’, no work

was to be executed, unless specific

instructions were received directly from the

Company.

Two Risk Assessment Analysis forms with

Code nos. TE006 and TE007 were filled

prior to the specific maintenance work on

the main steam delivery valve of boiler no. 2

was initiated. The activities were defined as

‘Boiler Overhaul – Water Side’ and ‘Boiler

Overhaul – Gas Side’. Both were assigned

the (acceptable) risk level ‘3’.

The forms seemed to suggest that the

incorporated hazards were not correlated

with the specific task to be undertaken. The

only relevant hazards seemed to be crew

fitness, crew eligibility, high temperatures,

side effects from steam production stop and

lack of personal protective equipment. All

these hazards had been assigned risk level

‘0’ apart from the high temperatures risk,

which was assigned risk level ‘2’.

The aim of a risk assessment exercise is to

qualify whether the status of any system is

acceptable and help determine what changes

are necessary to make it acceptable. Such

exercise is so important that it will not only

provide an estimate of the size of risk, but

should also enable a comparison of the risk

level with some given criteria and serve as a

platform for a professional judgement to be

made in determining what system

improvements are needed to increase safety.

Whilst risk assessments are part of

organisational functioning, they are also

strongly influenced by each individual’s

unique experiences and interpretation of the

‘input signal’. Understanding risk is vital as

it correlates to the degree with which risk is

observable.

Risk perception is the understanding of

perceptual realities and hazard indicators.

The residual steam / hot condensate water in

the one-metre long pipe and the valve body

was a hazard – and a very serious one.

However, it was not detected. What

distorted the perception of the crew on the

severity of the hazard was the lack of

perceptible indicators.

Thus, the lack of depth of the risk analysis,

influenced by the distortion mentioned

above, and the lack of past experience of

similar accidents, precipitated into a

situation where the crew members could

only react in a reflex mode as a result of the

sudden occurrence of escaping hot

condensate water and steam.

The problem with lack of perceptible

indicators is a hazard per se and this

phenomenon is not endemic to a particular

safety critical domain. Studies in domains

other than maritime transportation also

revealed similar problems. It was revealed

that less than half of the hazard indicators

were perceptible to the human senses and

almost a quarter had to be perceived and

inferred from comparisons with standards.

As indicated above, lack of past experience

was also an identified common problem –

retrieval from memory would have only

occurred if the crew members had past

experience of similar accidents or incidents.

Evidence showed that none of the crew

members had experienced similar accidents

in the past.

Studies in hazard perception revealed the

intricacy of the process, with different

cognitive processes involved. It is also

acknowledged that inaccurate hazard

perception is a source of limited hazards

control.

MV Seasong 201307/004 11

Situation awareness

Maintenance activities cause deviations

during normal operations. Thus, whilst

maintenance increases component reliability

and hence safety, accidents often occur

during maintenance. The importance of risk

assessment has already been described

above. From the perspective of situation

awareness, risk assessment is equally

crucial.

Risk assessment is a process (which depends

on, inter alia, perception), that will generate

a person’s knowledge of the system or

situation awareness. Naturally, the

distinction between risk assessment and

situation awareness may not necessarily be

crystal clear and some scholars even claim

that psychology is unable to separate the

process from the product.

To a certain extent, the safety investigation

has considered the two separately.

However, what is of utmost importance is

the understanding that rather than two

mutually exclusive constructs, risk

assessment and situation awareness are

interdependent. It is submitted that situation

awareness also arises from the interaction

between crew members and the work

environment – and risk assessment is one

way of ensuring crew ‘a healthy’ members-

environment interaction.

Thus, situation awareness is a phenomenon,

which is not only identifiable with the

individual but, as expressed scientifically, is

a function which is achieved by coordination

between the human and the environment

within the socio-technical system on board.

The link between risk assessment and

situation awareness is that the former is vital

to pave the way for a compatible

representation of people and systems i.e.

when the awareness of system status in the

minds of the crew members becomes a true

reflection of the actual and real status of the

system. Incompatible representations (either

on the crew member’s side or the machine’s

status) would definitely mean potential

problems. This accident was a case in point.

What actually happened prior and during the

unfolding of the events was that the chief

and second engineers were neither able to

comprehend accurately the system status nor

to accurately project its future status.

CONCLUSIONS

1. Pressurised steam and hot condensate

water was trapped within the

approximately one-metre length of

pipe section between the main valve

and the isolation valve 48V and the

valve body;

2. The thermal energy of the condensate

trapped at relatively high temperature,

changed into pressure energy during

the cooling down period, eventually

ejecting the steam / hot condensate

through an exit point, provided as a

result of the removal of the valve

bridge.

3. There were no available means to

verify whether there was any residual

pressure within the isolated pipe

section between the main valve and

valve 48V.

4. The injuries sustained by the second

engineer confirmed that he was not

wearing adequate protective clothing.

5. The risk assessment analysis forms

seemed to suggest that the hazards

incorporated in the Forms were not

correlated with the specific task to be

undertaken.

6. The chief and second engineers were

neither able to comprehend accurately

the system status nor accurately

project its future status.

MV Seasong 201307/004 12

RECOMMENDATIONS3

Thenamaris Ships Management Inc. is

recommended to:

18/2014_R1 Bring this safety

investigation report to the attention of

crew members serving on board

Company ships and highlight the

potential dangers of hot condensate

being trapped within parts of the steam

system;

18/2014_R2 Ensure that its SMS highlights

the importance of continuous awareness

of the efficient drainage of hot

condensate, where possible and

sufficient cooling before any

maintenance work is carried out.

3 Recommendations should not create a

presumption of blame and / or liability.

MV Seasong 201307/004 13

SHIP PARTICULARS

Vessel Name: Seasong

Flag: Malta

Classification Society: American Bureau of Shipping

IMO Number: 9290438

Type: Oil Tanker

Registered Owner: Rose Navigation Limited

Managers: Thenamaris Ships Management Inc.

Construction: Steel

Length Overall: 244.0 m

Registered Length: 235.8 m

Gross Tonnage: 57162

Minimum Safe Manning: 18

Authorised Cargo: Liquid bulk

VOYAGE PARTICULARS

Port of Departure: Sidi Kerir, Egypt

Port of Arrival: Ceyhan, Turkey

Type of Voyage: Short International

Cargo Information: In ballast

Manning: 24

MARINE OCCURRENCE INFORMATION

Date and Time: 06 July 2013 at 1115

Classification of Occurrence: Serious Marine Casualty

Location of Occurrence: 36° 19.5’N 035° 11.8’E

Place on Board Engine-room

Injuries / Fatalities: One serious injury

Damage / Environmental Impact: None

Ship Operation: Special Service - Drifting

Voyage Segment: Transit

External & Internal Environment: Slight seas with a South-westerly 0.5 m swell,

Southerly wind Beaufort force 2 and air

temperature of 28°C.

Persons on board: 24