There is a huge buzz happening when it comes to the marine environment, especially with MEPC 69 concluding just a couple of weeks ago. While it is definitely an appreciable effort taken by IMO, MEPC and various other bodies, hardly anything is done to protect seafarer from accidents. Many can say that they have devised a system or a software to save seafarers, but not one is fool-proof or good enough to implement it with ease. Many reports claim that accidents happen as the safety systems are being overlooked or not effectively utilized.
Here is an incident reported/published by the Nautical Institute where the Master of the ship died on board an oil tanker in which an oil sampler had to be recovered from an empty tank. The atmosphere was found to be 20.6% oxygen, with the hydrocarbon at 26% LEL. The Master approved the risk assessment and work plan for two crew members to enter the space with emergency escape breathing devices. When they reached the tank bottom, the men felt dizzy; one exited but the other collapsed. Despite being warned not to, the Master entered the tank and was overcome. Although both men were brought out by crew wearing breathing apparatus, the Master could not be revived.
The Incident:
While discharging an oil cargo from a tanker, an oil sampler (similar to that shown in the photograph) was lost to the bottom of tank 3P. It was decided that once the discharge was finished and crude oil washing completed, the sampler would be retrieved before loading the next cargo into 3P to avoid any potential damage to the ship’s equipment from the sample bucket or tape.
Once empty, the tank was ventilated. Over several days, the tank atmosphere of tank 3P was measured using an explosimeter and sample hose. Although oxygen was near normal levels, HC was at 57% of LEL on day one of ventilation and 38% of LEL on day two. After discussion, it was agreed that entry into 3P tank would start the next morning (day three) if the gas levels were ‘less’.
The next morning, the tank atmosphere of 3P tank was found to be 20.6% oxygen, with HC at 26% of LEL. Tank entry equipment was prepared and placed near the tank access hatch; breathing apparatus (BA) sets, emergency escape breathing devices (EEBDs), stretcher and heaving lines. The Master was shown the risk assessment and work permit for enclosed space entry and although the HC LEL was indicated at 26% he stated that the oxygen content was good. It was decided that two crew should go in, each wearing an EEBD.
Two crew members entered the cargo oil tank via the tank access hatch each with an EEBD worn over the shoulder, a torch and a personal gas meter. Several other crew members and the Master were in attendance at the tank access hatch. The lead crew member proceeded down to the first platform and checked the atmosphere across the platform with his gas meter. The second crew member then proceeded down the stairs to meet him. This was repeated for the remaining platforms until they reached the tank bottom almost 20 meters below the main deck. The lead crew member then reported feeling dizzy and heard his personal gas meter alarming. The second crew member reached the tank bottom and instantly felt the effects of the gas inhalation; he also heard his personal gas meter alarming. The lead crew member shouted and gestured to the second to wear his EEBD and leave the tank. The lead crew member felt dizzy and immediately proceeded to exit the tank. The second attempted to don his EEBD and activate it but collapsed soon afterward. Meanwhile, on deck, the Master entered the tank with an EEBD worn over his shoulder. Although another crew member warned the Master not to enter the tank the Master nonetheless proceeded into the tank. Two crew members on deck donned the BA sets already available at the entrance.
Some Questions to you:
- Do you think an oxygen level of 21% with hydrocarbon at 26% safe?
- What does your SMS (Safety Management System) say on the Hydrocarbon content during a tank-entry?
- Why the crew entered the tank without SCBA? Do you think wearing an SCBA would have prevented such a scenario?
- Wearing an SCBA and carrying an EEBD would have been a wise option – may we have your thoughts on it?
Do you have any other recommendations to enhance safety breaches or fortify your Safety culture?
Write to us to share it with the Maritime World at experts@mfame.guru
Did you subscribe for our daily newsletter?
It’s Free! Click here to Subscribe!
I am maritime university visiting faculty and external examiner and assessor with DGS Kanjurmarg East Mumbai Capt CM Srivastava Mumbai
As Chief Officer, 18 years on vlcc, 42 years at sea.
Isgott is very clear, Hc max 1% lel, O2 20.8% min (preferable 20.9%) H2S and Benzene 1 ppm max (preferable nil ppm).
I would never enter tank what is unsafe for entry even with BA sets – not enough paid for such risk and even if I will lose job.
You have to measure gases in two different openings and in three levels, top mid bottom. Ventilation must be stopped at least 10 minutes before measuring and forced air ventilation (read water powered air fans) must run during tank entry.
Do not forget to put blank on Ig pipe on ceck in order not to contaminate gas free tank from other unsafe tanks!
Always crude oil wash (in port) tank before entry, then water wash, then purge from hc gases until LFL is < 2% by Vol, then put air ventilation until you have 20.9% O2, lel nil and h2s and benzene nil.
And take other precations according Isgott and company manual.
In each tank I always as CO enter first.
Question is why still accident happen during tank entry?
Reluctance to use SCBA and not considering higher HC concentration at bottom of tank seems to be the immediate cause. Risk assessment wasn’t comprehensive enough.
Hi to everyone!my thoughts Its simple follow standard procedure/company procedure for enclosed space entry;
1.make risk assesment(sign by responsible person)
2.oxygen should be 20.9% /hc less than 1%,h2s 0 & other gases 0%
3.keep ventilation running,keep monitor tank atmospher by lowering gas detector hose to the bottom part
4.rescue equipment ready
5.enough people standby in entrance for rescue.
6.entry person should carry personal gas detector/vhf radio(immedietly out if gas detector alarm)
7.it is wise to bring EEBD
8. the attending person in the entrance should always check the condition of entry person by calling in vhf by interval of 1minute(if no response be ready for rescue wear scba/call other assistant)
9.(again)never attempt to enter the tank when tank atmospher not reach 20.9 ,hc below 1% & other gas 0%
Hi,
I agree with Mr.Premi
on the other perspective, ” why the oil sampler lost in the tank? Material failure(too old or poor quality), users inexperience etc.. and why the ship crew insist to take the sampler back without sufficient ventilation ?
Seems an ingrained reluctance to don BA, which would likely have avoided the fatality (and further potential fatalities). HC vapours may be heavier than air so lower o2 concentration lower in the tank. These may also a narcotic effect (not just the fire or explosion hazard)….
Dear Mr. Premi,
thanks for your comments.
May we request you to share your thoughts on HC%.
is it 0% HC or otherwise?
Please feel free to write to us about your thoughts on how to prevent such incidents apart from regular checklists. your insights will help the maritime world to look into a new perspective
Thank you
Root cause seem to be one or more combinations of below:
1. Lack of training, including master. EEBD is for ESCAPE & not for ENTRY. SCBA is to be used for entry in enclosed space.
2. Tank was not ready for entry with 26% HC (it is too high) ISGOTT recommends max HC level at 1% LFL, H2S content was not measured.
3. Company procedures were not robust.
4. if #3 is false then there is lapse of ISM and company procedures are not followed, audits are not done properly.
4.there is no mention of continuous ventilation in the report, guess it was not done.