We are all Doomed (again)

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Big Pete
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We are all Doomed (again)

Post by Big Pete »

Interesting article below from the Royal Institute of Naval Architects, about the prevalence of High Blood Pressure in Seafarers, it appears that 20 years of exposure to the normal noise levels in a ship's Engine Room can cause it, apart from all the other issues relating to smoking, drinking, diet, stress, lack of exercise, social isolation, breathing fumes etc.

High noise, high blood pressure?

Blood Pressure

High blood pressure, or arterial hypertension, is a chronic condition that appears insidiously in middle age.

The causes are difficult, perhaps impossible, to identify with certainty; it could be caused by genetics, lifestyle, related to an underlying health condition, or any combination of these factors. A further problem arises in determining what bearing hypertension may have on mortality and as an underlying cause for other afflictions such as strokes and heart disease.



The prevalence of hypertension among seafarers is well established and, some might say, unsurprising. Historically, seafarers are habitually unhealthy; smoking, high cholesterol and obesity, combined with a sedentary lifestyle in which they can spend long hours confined to increased risk. British-Danish research in the 1980s and 1990s found that cardiovascular disease (for which hypertension can be a contributory factor) accounted for 55–70% of all natural causes of death among seafarers. Another study in 2016 found that Danish seafarers were three times more likely to be diagnosed with hypertension than a reference group, with the high rate among younger seafarers being a particular cause for concern. Similar studies have found the same for French, Spanish and German mariners.



What's more contentious is the possible connection between shipboard noise levels and high blood pressure. A 2020 review of epidemiological studies by German researchers published in The International Journal of Environmental Research & Public Health found what it described as a 'high quality of evidence' that occupational noise exposure increases the risk of hypertension, concluding that above the 'safe' level of 85dB, 'the risk of developing hypertension was more than three times higher relative to the comparison group'.



Engine room prevalence



Among the papers selected for that review was a 1986-published French study led by Dr. Dominique Jégaden, a specialist in seafarer health and subsequently president of the French Society for Maritime Medicine. For this study, 455 seafarers were recruited aged between 40 and 55 years old. The diminished hearing sensitivity at higher frequencies, or audiometric 'notch' at 4,000Hz that's typical of regular subjection to noises over 85dB, was found to be common among the 164 room personnel but not so the 291 deck crew. Furthermore, there was increased prevalence of confirmed hypertension among the engine room personnel (19%) compared to deck crew (11%, typical of the general French male population of the same age at that time).



The study found no statistical relation between hearing loss level and hypertension, and was independent of other hypertension risk factors such as obesity, alcoholism or heredity. However, it did find a link between hypertension and those seafarers who had spent more than 20 years subjected to unsafe noise levels.



"Concerning seafarers, this problem has been studied very little because I think I am the only researcher to have worked on this subject," Dr Jégaden tells The Naval Architect, 35 years later. "The interest of the seafarers who are included in my study was that they all came from the same region (Brittany), that they had the same way of life, that they were embarked on the same merchant ships, that they ate the same food, that they had the same average age and an equivalent smoking... In short, the only thing that differentiated them was the noise exposure among the mechanics, compared to the deck crew."



He adds: "My statistical study also showed an odd-ratio of 1.62 and an independent relationship to other causes of hypertension such as heredity or obesity. I concluded that this relationship does exist if the occurrence of hypertension is related, on the one hand, to a high level of noise (>85 dB(A)) and, on the other hand, to a duration of exposure to noise for more than 20 years."



Despite this, Jégaden is reticent to state with certainty that there is a link between hypertension and noise. "Studies where published which show that cardiovascular morbidity and mortality are important in seafarers. But it is difficult to link this to only hypertension, because other causes are also very present in this population."



The adoption of IMO's Noise Code (Resolution MSC.337 (91) in 2012 (effective since 1 July 2014)), established requirements for vessels ≥10,000gt that Jégaden believes should also be valid for smaller vessels. Nonetheless, he recommends a level of <50dB (A) for sleeping areas, since below this threshold allows for a good night's sleep.



He notes that significant progress has been made in soundproofing in recent years, particularly on cruise ships, although this appears to have been done for passengers' comfort more than that of the crew. In all likelihood most operators of merchant ships would baulk at the additional capex.



"Concerning propulsion, diesel-electric propulsion is an excellent compromise to reduce noise onboard. The automation of the means of propulsion also makes it possible to significantly reduce the working hours of mechanics, due to the noise, and therefore to reduce the risk. But maybe we will have to wait some years to hope to notice an improvement in the health of these seafarers," Jégaden concludes.

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JK
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Re: We are all Doomed (again)

Post by JK »

This is fascinating.
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Merlyn
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Re: We are all Doomed (again)

Post by Merlyn »

Blimey
Should have stayed in bed then
Remembering The Good Old days, when Chiefs stood watches and all Torque settings were F.T.
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Merlyn
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Re: We are all Doomed (again)

Post by Merlyn »

Ha,
Omission here methinks?
No mention of prop cavitation here, working in the shaft Tunnel for periods of time? (DE V Conventional set ups? )
Or bagging a cabin above a prop and below the steering gear motors etc?
And at certain " Critical " rpm that table in your cabin walking again?
What about Anzipod set ups?
What's the stress factor of pulling the ship through the water versus pushing it?
Also the report fails to mention the effects on mental health of that cabin directly above No 9 cylinder head and the well known facts of being in a deep sleep, the engine note changes, small noise variation and wallop, wide awake.
( learnt that one early in the 1960's - weird but it's true )
So as dear old JJ would have said,
4/10 only.
Remembering The Good Old days, when Chiefs stood watches and all Torque settings were F.T.
Chummyjigger
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Re: We are all Doomed (again)

Post by Chummyjigger »

Nice to see that someone is taking an interest in our health. I have had weight issues for most of my life and it was spiraling out of control for several years peaking in December 2018. The threat of heart disease and diabetes scared the pants off me, so for years I racked up many hours per week walking. I am convinced that the walking all those years helped maintain a level of health that kept me off medications. I attempted to eat healthy but, failed miserably.
In 2018 my friend introduced me to the zero sugar low carbohydrate community. The person I follow has a 24 page PDF with all the information I required to get started. Basically, if it has sugar, “Don’t Eat It”! The PDF also explains how carbohydrates convert to glucose when digested, thus raising your blood sugar levels. I am thoroughly convinced that sugar is pure evil and that it is to be avoided at all costs.
It was a major eye opener eliminating sugar and carbohydrates from my life.
Heart disease and diabetes are no longer a concern.

As for this article: it would be interesting compare the blood work of the participants. All the information I read says that the majority of people are low in vitamin D and magnesium. The majority of people that suffered more severe effects of covid were low in vitamin D. The majority of people are low in magnesium. The soils are depleted of magnesium. Magnesium is a type of salt that does many things in the body and it contributes to healthy arterial walls.

I also recommend people read the 8 minute article by Dr Cate. She explained the 8 oils that should be avoided.

https://drcate.com/the-hateful-eight-en ... ur-health/

For any heart health or cholesterol concerns I would recommend Ivor Cummins. He has a podcast called the Fat Emperor.
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