Thursday, December 16, 2010
RESPIRATORY FILTERS ON CHEMICAL TANKERS -- CAPT AJIT VADAKAYIL
Most oil major vetting houses, nowadays discourage Annex 2 chemical ships from keeping respiratory filters on board--the reason touted being-- sailors don't know how to use it!
This means if some ignorant , untrained pretender 2nd officer does NOT know how to use ECDIS -- all ships in the world must be penalised, and ECDIS must be removed from all ships.
In your company if filters are banned--the parcel chemical master must make a strong protest by SMS system.
The " Alices in wonderland " ashore have no idea, what it takes to squeegee a cargo tank containing nauseating fish oil laden with vermin and viruses -- or how to clean up a bio accumulative spill in the manifold drip tray.
Have the law makers ever tried to squeegee a hot slippery tank with SCBA sets?
In any case SCBA sets are NOT meant for "working". The " working time" in IBC code refers to " lung demand time".
These jokers will take a flight to the capital city of their country , if they have to fill up a application form in capital--- at sea we sailors are handicapped by such riff -raff sitting on important chairs ashore -- who have reached there by tilted playing fields NOT by merit.
Back to business--
ALWAYS STUDY THE INSTRUCTIONS ON THE USER INSTRUCTION SHEET.
Respiratory filters are consumer goods and require no maintenance. They ensure good protection against gases and vapours , toxic particles or borth combined.
Choose the type of filter as per the requirement.
The oxygen content should be atleast 19.5 %. Air purifying respirators must NOT be used to protect against H2S. Leave the work area immediately, if breathing becomes difficult or dizziness or other distress occurs, encouraging all others individuals too in the same area.
Exposure to an oxygen deficient atmosphere can result in unconsciousness, paralysis, brain damage or even death. Initial symptoms of oxygen deficiency are:
Headache, Drowsiness, Nausea, Weakness, Dizziness, Deep or laboured breathing, Unconsciousness.
When dust or aerosols are present , use anti-dust or gas –dust combined filer.
PARTICLE filers of inert matters, low toxic particles and bacteria/ virus are available in the market.
GAS filers are available for—
Organic vapours with BP> or < 65 deg C
Organic gases like chlorine , H2S , ammonia and SO2. You can combine various types in one filter. Note the one-way arrow printed on the body of the filer. Ensure that the seal is always present. The filters have an expiry date.
There are filters which can aDsorb at low, medium and high capacities.
Crew with beards and deep scars at the sealing areas are at risk due to leaks.
If a filter is damaged or battered do not use it.
The duration os a anti-gas filer depends on the aDsorbsion capacity of the aDsorbent agent, concentration in contaminanat, RH of air, temperature and lung demand of the user.
The filer must be immediately replaced if you can smell the gas or vapour.
As far as particles filters are concerned , inhalation resistance indicates filter clogging. When breathing becomes difficult change the filer, though protection is still satisfactory.
When the contaminant is toxic , it is recommended to use the filter only once.
Store the filters fitted with their caps in a cold and dry space free of toxic vapours. Do not store outside the temperature range -20C to+50C, or with RH>90%.
Do not use the filter 6 months after the first opening, or as mentioned in the instruction sheet.
Filter masks can be used only 3hrs in a working day.
Use proper face masks when sweeping health hazardous cargoes like yellow grease ( crushed bone meal ), tallow etc.
When removing a mask take care not to breathe in the contaminants on the external surface of the filter.
Filter mask— full face with nose cup to prevent fogging, inhalation and exhalation valve
Organic vapor cartridges are no use for inorganic vapors.
Never remove a mask before leaving the contaminated area.
Filter protection must only be used against gases which has a distinctive smell and there is no lack of oxygen. If you can smell gas it means the filter is saturated and is to be discarded.
Class 1/ 1000ppm
Class2/ 5000 ppm
Mark X/ low BP products
When loading Carcinogenic, Toxic or Bioaccumulative cargoes, spot checks of vapor concentrations should be carried out with Draeger tubes, to ascertain is TLV-TWA are being exceeded, and if PPE like face filters or SCBA should be worn by watchkeepers.
The Vervey’s tankcleaning guide gives the VP/TLV ratio--- anything more than one is dangerous requiring the use of Draeger tubes on deck. Epichlorohydrin is 17, Methanol is 0.46 (200/92)
Personnel directly involved in the disconnection of toxic chemical cargo hoses should wear suitable filters / respirators.
Personnel supervising the disconnection of cargo hoses should stand upwind of, and away from, the operation.
When squeegeeing tanks at end of veg oil/ fats discharge , the portable vents must run -- oxygen content must be at least 19.5% for short time exposure ( 20% for longer time ) --use the 4 runner portable gas instrument to check for CO and H2S.
Fill up a risk assessment form when sailors, have to wear air filters, with SEVERITY and PERIOD OF IMPACT/ CERTAINTY on the matrix. . This ensures that Chief officer or Master is involved in selecting the filter mask. Animal fats / fish oil squeegeeing requires virus masks.
CAPT AJIT VADAKAYIL