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Methanol
So what is this stuff ???????
Firstly, methanol can also be known by several other names:
Methyl alcohol Methyl hydrate Methyl hydroxide Wood alcohol
Methanol
The black is the carbon atom.
Attached to that are three hydrogen atoms – in white.
Also attached to the carbon atom is one oxygen atom, in red, which in turn has another hydrogen atom attached to it.
Methanol
In the real world, is this water or not – be careful !!!!!!
It might also be:-
Gin or Vodka or even
METHANOLVisually, you cannot tell the
difference
Methanol
So assuming that it is in fact methanol and therefore (unfortunately) not gin or vodka – can methanol harm me ????
And the answer is YES
Methanol has been around since the days of the early Egyptians and people have been using it incorrectly from that time, right up to the present day with quite often, fatal results.
Methanol – health effects
If you swallow it, inhale it or absorb it, (depending on the quantity) you run the risk of it being dangerous to your health.
The initial symptoms of methanol intoxication are indicated by the Central Nervous System being depressed, i.e:
Headache / dizziness / nausea / lack of coordination / confusion / drowsiness and with a sufficiently large dose, unconsciousness and death.
Methanol – health effects
So what do we mean by a “sufficiently large dose” ??
Generally, this is now accepted as being 100 to 125 ml or 4 fl oz – that’s all it takes.
Once the initial symptoms have subsided, a second set of symptoms will appear between 10 to 30 hrs after the initial exposure.
This is due to the build up of toxic material in the blood and may result in respiratory failure.
Methanol
So don’t even think of drinking it or else you will be very sick and most likely, will die.
Methanol – personal safety
ALWAYS, ALWAYS, ALWAYS
wear the appropriate personal protective equipment when handling methanol.
Methanol – first aid
Do not get it into your eyes or ears, or onto your face, hands and skin.
If that happens, especially with your eyes, you must rinse thoroughly with fresh water for at last 15 minutes and seek medical assistance.
Methanol - fire
Lets talk about fire, does this stuff burn?
Yes it does, BUT in daylight you cannot see any flames at all – they are invisible !!!!!!!!!!!!!!!
At night, you may be able to see a faint blue flame.
Methanol - fire
Also there is no smoke, so the only indication you will have of methanol being on fire is possibly seeing the heat waves rising.
No smoke, hmm, where is the wind coming from ?
If you are at sea, maybe you need to alter course and speed to keep the fire away from crucial areas of the vessel.
Methanol - fire
If you are going to fight the fire with a fire extinguisher, a dry powder one is probably the best choice.
Methanol - fire
But if you start to fight the fire with water, remember that it will continue to burn with at least 4 parts of water
to 1 part of methanol.
So you need to use lots of water.
Methanol – tank safety
Remember that a methanol concentration above 200 ppm will be harmful to you as an individual.
If the cargo tanks on your vessel are less than 3,000 CBM’s, then the current law states that you do not need to have the tanks inerted – they can be left full of methanol vapour.
Lets talk about this vapour stuff
Methanol - vapour
Remember you cannot see it and in all probability you may also not be able to smell it.
If there is zero wind over the decks when you are loading then the vapour that is ejected from the P/V valves will just hang around over the decks and not disperse.
You have to be safe and try to get yourself away from this vapour as continuously breathing it into your lungs is definitely not healthy.
Methanol tank entry
So do you really need to go into the tanks?
If yes, then how do you know the tank is safe to enter?
What precautions do you take before entry- have you taken ALL safety measures?
Have you completed a checklist?
Have you checked the tank atmosphere?
Do you have a man on stand-by at the tank access hatch?
Do you know that you can be overcome by fumes just by looking into the open tank access hatch without wearing breathing apparatus?
Health effect due to lack of oxygen
% Oxygen Effects & symptoms
23.5 Maximum ‘safe level’ (23.5% is often the high level alarm setting on most O2 detectors)
21 Typical O2 concentration in breathable air
19.5 Minimum ‘safe level’ (19% is often the low level setting on most O2 detectors)
15-19 First signs of hypoxia. Decreased ability for strenuous work. May induce early symptoms in persons with coronary, pulmonary or circulatory problems
12-14 Respiration increase with exertion, pulse rate increases, impaired muscular coordination, perception & judgement
10-12 Respiration further increases in rate and depth, poor judgement, lips turn blue
8-10 Mental failure, fainting, unconsciousness, ashen face, blueness of lips, nausea, vomiting, inability to move freely
6-8 6 minutes exposure – 50% probability of death
8 minutes exposure – 100% probability of death
4-6 Coma in 40 seconds, convulsions, respiration ceases, death
Methanol - Safety
So what else is there to be aware of?
You already know about this one, so smoke ONLY in designated places in the accommodation and NEVER on deck.
Methanol - Safety
Make sure that the tools you use on deck do NOT have the capability of producing a spark.
This is really, really bad !!
Methanol - Safety
Nobody but nobody should have a cell phone powered up on deck.
If you see ANYONE with a cell phone on deck, check to see if it is powered down, if not, tell them to turn it off.
Methanol - Safety
Your communications radios (VHF or UHF) MUST be “intrinsically” safe and should only be able to operate on 1 watt power setting.
Methanol - Safety
If you see anyone using a flash camera that is not intrinsically safe tell them that it is not allowed and do not take NO for an answer.
Methanol - Safety
Finally, no matter what:-
Make absolutely sure that all the PPE and safety equipment issued to you or supplied by the ship is ALWAYS in 100% operational condition.
If you find that something is wrong – TELL SOMEONE – PREFERABLY THE SAFETY OFFICER OR THE MASTER do not walk away and assume that someone else will fix it.
Remember that YOU are responsible for your own well being and safety.