USCG Warns of Tank Sampling Dangers

MaritimeProfessional.com
Thursday, January 09, 2014
Photo: USCG

This Safety Alert serves as a reminder to Coast Guard (CG) personnel and the maritime community of potential dangers during sampling of cargo tanks. During a recent Port State Control (PSC) tank vessel examination, a CG member was exposed to a dangerous concentration of Hydrogen Sulfide (H2S) gas and suffered a serious injury.

The exposure occurred during a tank vessel exam onboard a tank vessel carrying Grade E Sour Crude. A PSC team requested a ship's crew member check cargo tank oxygen levels using the ship’s portable gas meter. The crew member accessed the cargo tank via a deck sounding valve similar to the adjacent photo. When the valve was opened the pressurized cargo tank atmosphere escaped releasing inert gas and H2S vapors.

During the evolution the personal gas meters of two individuals involved (one CG and one crew) alarmed for H2S. The CG officer whose alarm sounded was standing 1-2 feet downwind from the sounding valve. Within days the CG officer developed severe exposure symptoms consistent with H2S exposure. The other two CG officers involved were standing upwind. Afterward, one reported experiencing a minor headache.

OSHA notes that H2S is a colorless, flammable gas with a “rotten egg” smell that occurs naturally in crude petroleum. Even at low concentrations this heavier-than-air gas can irritate the eyes, nose, throat and respiratory system with effects delayed for hours or days. At higher concentrations, nausea, vomiting, headaches, dizziness, unconsciousness or death may occur. While the initial “rotten egg” odor is present, an individual may lose the ability to smell that gas after becoming exposed. Personal monitoring equipment is, therefore, vital to protect against exposure. An alarm on H2S constitutes an acute exposure and should trigger immediate evacuation and initiation of acute exposure procedures including medical attention.

Prior to using portable gas monitoring equipment, personnel should familiarize themselves with ISGOTT Section 11.8 and safe work practices for conducting or witnessing these tests. ISGOTT recommends when sampling tanks personnel should stand perpendicular to the wind to avoid being downwind or upwind and creating eddies. When monitoring cargo tank atmospheres, all personnel should exercise diligence and great care. In all cases, personnel should completely assess the risks, to include the cargo type, tank pressure, venting arrangements, wind direction/speed and condition of the testing equipment. When H2S is suspected to be present, ISGOTT Section 2.3.6.5 recommends that a self contained breathing apparatus (SCBA) be worn if it is necessary to breach the integrity of the cargo system and if a vapor free atmosphere cannot be guaranteed.

The American Conference of Governmental Industrial Hygienists recently reduced the H2S dangerous Threshold Limit Value from 2 parts per million (ppm) to 1 ppm.

As a result the Coast Guard strongly recommends that those involved in cargo tank sampling or atmosphere testing:

• Be familiar with and adhere to ISGOTT safe work practices.
• Assess personnel risks.
• Don appropriate personal protection equipment including gas monitoring detectors, respirator or SCBA.
• If gas monitoring detectors are used ensure:
o detectors are maintained and properly calibrated
o alarm settings values are properly set
• Be aware and familiar with the hazards of the cargos involved as well as exposure indicators and emergency response procedures.

uscg.mil
 

Maritime Reporter July 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Tanker Trends

Second Tanker Waits to Load Oil at Libya's Reopened Port

A second tanker is waiting to load oil at Libya's Es Sider port, state-run National Oil Corp (NOC) said on Thursday, as the country's biggest crude export terminal

Mozambique: $30b Invested for 2018 LNG Export

More than $30 billion will be invested initially in Mozambique's natural gas sector to build capacity to produce 20 million tonnes per year of liquefied natural gas (LNG),

The World's Most Expensive Jones Act Tanker

The series highlighting the world's most expensive active vessels from online ship intelligence and information service VesselsValue.com focuses this week on the most expensive tanker vessel,

Marine Equipment

Container Manufacturer Reports Profit Plunge

World-leading container manufacturer and logistics services provider Singamas Container Holdings Limited (Singamas) has  announced its unaudited interim results for the six months ended 30 June 2014.

USS Independence Successfully Completes Special Trials

USS Independence (LCS 2) successfully completed Special Trials (ST), a series of at-sea tests on Aug. 2, following the ship's participation in the multinational

Krill Supplies VFMMS to Island Tug and Barge

Krill Systems Inc., a producer of Vessel Fuel Measurement and Monitoring Systems (VFMMS), announced delivery, installation and successful sea trials of three more systems to Island Tug and Barge Ltd.

Barges

Port Metro Vancouver Approves $15m Coal Transfer Project

Port Metro Vancouver, Canada's largest port, said on Thursday it has approved a new facility to transfer coal from trains onto barges at Fraser Surrey Docks, a

LNG America Selects Topside Designer for LNG Bunker Barge

LNG America has selected Taylor-Wharton to commence the front-end engineering and design work for the cryogenic topside of the company’s 3,000 cubic meter Gemini

Xervo and SH Group Expanding in Norway

The possible introduction of the NORSOK R-002 standards means there’s a big job to be done upgrading the lifeboats and rescue boats onboard the rigs already operating in the Norwegian sector.

Maritime Safety

Massive Haitian Refugee Rescues off Bahamas

Coast Guard crews and Royal Bahamian Defence Force (RBDF) rescued more than 400 Haitians illegally migrating in three separate at sea interdictions in the span of 11 days, informs the US Coast Guard.

Maersk Line Still the Leading Carrier on Reliability in Q2

During the second quarter, the overall industry reliability has improved. However, Maersk Line is pleased to have improved their performance so that they can

CBP Aircraft Locates Vessel in Distress

U.S. Customs and Border Protection Office of Air and Marine agents assigned to the North Dakota Air Branch have located four people on Red Lake after a call

 
 
Maritime Careers / Shipboard Positions Maritime Standards Naval Architecture Offshore Oil Pipelines Pod Propulsion Port Authority Salvage Ship Simulators Winch
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1187 sec (8 req/sec)