Preparing equipment
Once the equipment has been secured, the technicians need to make sure everything is working order. This can involve checking for defects, making sure certificates are in date, replenishing consumables such as oil, calibrating, and pressure testing.
Coping with pressure
On the left is a normal sized human head made of polystyrene, next to it are the same heads put under pressure equivalent to 684m and 6840m depth.
The pressure of the Earth’s atmosphere is pushing on you at round 1kg per centimetre squared. It pushes equally in every direction but the pressure doesn’t crush you because your body pushes back with equal force. The only time you feel the pressure is when it changes; a strong wind, going up in a lift or when your ears pop.
Underwater there is the pressure of the atmosphere plus the pressure of the water, this pressure is measured with units called bar. At sea level the pressure equals one bar, and increases by a tenth every meter down, so at 10 meters down the pressure is twice of that at the surface (2 bar).
It is important that underwater equipment can cope with the pressure it will be exposed to and finding it can’t is too late when at sea. So before equipment is used it needs to be tested, but how can you recreate water five miles deep on land?
-
Pressure Testing
To recreate the kind of pressure found at the bottom of the ocean, NOC Southampton uses pressure vessels. There are two testing tanks that subject instruments and casing to extreme pressure, allowing technicians to measure their ability to be deployed at sea. Read more about pressure testing→
-
Calibration
Calibrations are performed on the instrumentation used throughout NMFSS to ensure the highest possible data quality for our end users. In essence, a calibration is just a comparison between an instrument and a known standard. A fully calibrated instrument will give a user confidence that the measurements they are taking are true and accurate. Read more about calibration→
