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Enjoy Wales
THE COASTLINE OF WALES IS A HIVE OF activity . The ocean provides food , shelter and a variety of life , bringing in food on the tide to reef-bound life forms . Sea fans and anemones filter out food morsels that flow around the shoreline . The ocean wastes nothing : all dead material is eaten by scavengers such as crabs , lobsters and eels . Smaller items are consumed by the final cleaning department , the shrimps .
Meanwhile , the drifters of the sea feed on the move . Jellyfish trail strands of stinging tentacles with nematocysts to paralyze small prey . All across Wales , the shoreline changes from sandy beaches to towering cliffs , to pebbles forever rolling in and out . Larger forms of life such as seals spread around our offshore islands , and even sunfish visit the dive boats when conditions are right . Having the second highest tidal range in the world , our dives are planned carefully , and local knowledge is recommended .
The downside to Wales is the weather : in winter we get cold rain , while in summer we get warm rain ! But when you get a good day it ’ s hard to beat . Great scenery in Pembroke and the Gower Peninsula all add to the enjoyment of a day at sea .
We have the benefit of wrecks and wall dives that vary in colour and depth . The sunsets and sunrises offer a broad spectrum of colour , especially when reflected off the sea ’ s surface . It is an everchanging world that we can all visit . From rock pooling to technical diving , enjoy Wales as a visitor and leave as a friend . PAUL WINKLEY , Swansea
Respect your cylinders
I READ SOPHIE HEPTONSTALL ’ S ARTICLE on the oxygen fire [ Safe oxygen handling , July / August 2024 ] with great interest , and wish to congratulate her on the clarity with which a very difficult subject has been reported . It is with subjects like this that BSAC and its magazine have sought to enhance the knowledge base of the general membership over the years .
If I may , I would like to reinforce some of the messages that she has made . Materials that would not burn in air can become highly flammable in the presence of high levels of oxygen . For example , you would not expect steel to burn , but in the presence of 100 % oxygen the adiabatic shock from a rapid release of O2 can be sufficient to cause ignition and rapid burning . Please do not use your cylinder charging area as a general storage place . You should never store inflammable items in an area where gas mixing is taking place . And , on all of the installations I have done in the past , I have always put the oxygen storage cylinders outside so that they are unlikely to release oxygen into the filling area .
With regards to the design of the charging area , take professional advice as to layout and get a suitably qualified engineer to do a risk assessment and supply a schematic diagram and maintenance schedule . This is a mandatory requirement under the pressure systems regulations . Finally , consult your insurance company to ensure that you are fully covered .
Please remember that the blending of mixed gases is a slow process . Personally , I have always used decanted oxygen through a panel which has an oxygen clean and oxygen compatible slow acting valves with restrictors in the inlet lines , followed by topping off from a storage bank . This has the benefit that the storage cylinder remains cool , whereas filling directly from a compressor , the air is hot .
I would take exception to one passage in the report regarding charging hoses . Rubber-covered steel braided hoses are fine for filling air cylinders , but they are designed
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