PADI dive theory – Equipment, is one of 5 subjects that will be tested on the PADI Instructor exam.<\/p>\n
We have made these materials available to help you to prepare for your PADI Instructor<\/a><\/span><\/strong> exam or PADI Divemaster<\/a> <\/span><\/strong>exam. If you choose to do your PADI Divemaster course or PADI IDC with Asia Scuba Instructors you will have access to many more materials in our ‘online classroom’.<\/span><\/strong><\/p>\n <\/strong><\/p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ admin_label=”Classes Section” _builder_version=”4.16″ background_color=”#ffffff” custom_padding=”4px||60px|” bottom_divider_height=”51px” global_colors_info=”{}”][et_pb_row column_structure=”1_5,1_5,1_5,1_5,1_5″ make_equal=”on” custom_padding_last_edited=”on|desktop” _builder_version=”4.16.0″ background_color=”RGBA(255,255,255,0)” custom_margin=”|||” custom_padding=”30px||0|” custom_padding_tablet=”” custom_padding_phone=”” saved_tabs=”all” locked=”off” global_colors_info=”{}”][et_pb_column type=”1_5″ _builder_version=”4.16.0″ background_color=”RGBA(255,255,255,0)” custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_button button_url=”\/padi-idc-divetheory-physics” button_text=”Physics” button_alignment=”center” _builder_version=”4.16.0″ _module_preset=”5fd97150-a814-4adf-a8ec-fdb80fa86603″ custom_button=”on” button_text_size=”15px” button_text_color=”#334A84″ button_border_width=”1px” button_border_color=”rgba(79,79,79,0.21)” button_border_radius=”5px” button_font=”||||||||” button_use_icon=”off” custom_margin=”||||false|false” custom_padding=”15px|10px|0px|10px|false|false” custom_css_main_element=”width:100%;||height:60px;” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][et_pb_column type=”1_5″ _builder_version=”4.16″ background_color=”RGBA(255,255,255,0)” custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_button button_url=”\/padi-idc-divetheory-physiology” button_text=”Physiology ” button_alignment=”center” _builder_version=”4.16″ custom_button=”on” button_text_size=”15px” button_text_color=”#334A84″ button_border_width=”1px” button_border_color=”rgba(79,79,79,0.21)” button_border_radius=”5px” button_font=”||||||||” button_use_icon=”off” custom_margin=”||||false|false” custom_padding=”15px|10px|0px|10px|false|false” custom_css_main_element=”width:100%;||height:60px;” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][et_pb_column type=”1_5″ _builder_version=”4.16″ background_color=”RGBA(255,255,255,0)” custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_button button_url=”\/padi-idc-divetheory-equipment” button_text=”Equipment ” button_alignment=”center” _builder_version=”4.16″ custom_button=”on” button_text_size=”15px” button_text_color=”#334A84″ button_border_width=”1px” button_border_color=”rgba(79,79,79,0.21)” button_border_radius=”5px” button_font=”||||||||” button_use_icon=”off” custom_margin=”||||false|false” custom_padding=”15px|10px|0px|10px|false|false” custom_css_main_element=”width:100%;||height:60px;” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][et_pb_column type=”1_5″ _builder_version=”4.16″ background_color=”RGBA(255,255,255,0)” custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_button button_url=”\/padi-idc-divetheory-skills-and-environment” button_text=”Skills & Environment ” button_alignment=”center” _builder_version=”4.16″ custom_button=”on” button_text_size=”15px” button_text_color=”#334A84″ button_border_width=”1px” button_border_color=”rgba(79,79,79,0.21)” button_border_radius=”5px” button_font=”||||||||” button_use_icon=”off” custom_margin=”||||false|false” custom_padding=”15px|10px|0px|10px|false|false” custom_css_main_element=”width:100%;||height:60px;” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][et_pb_column type=”1_5″ _builder_version=”4.16″ background_color=”RGBA(255,255,255,0)” custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_button button_url=”\/padi-idc-divetheory-decompression-theory-and-rdp\/” button_text=”RDP” button_alignment=”center” _builder_version=”4.16″ custom_button=”on” button_text_size=”15px” button_text_color=”#334A84″ button_border_width=”1px” button_border_color=”rgba(79,79,79,0.21)” button_border_radius=”5px” button_font=”||||||||” button_use_icon=”off” custom_margin=”||||false|false” custom_padding=”15px|10px|0px|10px|false|false” custom_css_main_element=”width:100%;||height:60px;” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ admin_label=”Classes Section” _builder_version=”4.27.4″ background_color=”rgba(232,241,255,0.5)” custom_padding=”||||false|false” global_colors_info=”{}”][et_pb_row admin_label=”Class Details Area” _builder_version=”4.16″ custom_margin=”60px|||” custom_padding=”60px|0px|29px|0px” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” locked=”off” global_colors_info=”{}”] Most scuba cylinders are made from aluminium or steel. Tanks can be made from other materials like titanium or fiber composites but they have very limited use in recreational diving.<\/p>\n Steel cylinders<\/strong><\/em> are negatively buoyant, even when empty. This means you need to carry less weight on your weightbelt. They can have a higher capacity (working pressure) than aluminium tanks. The primary disadvantage of steel cylindersis that they can rust easily.<\/p>\n Aluminum<\/em><\/strong> is a lighter metal than steel but, since aluminium tanks need to have much thicker walls to hold the same pressure, aluminium tanks are generally heavier<\/strong> than steel tanks with the same capacity. However, empty aluminium cylinders are positively buoyant in the water. Since they are a little heavier but also much bigger than steel tanks, divers need to carry more weights<\/strong> to compensate for this.<\/p>\n Aluminum corrodes just as steel but the aluminum oxide adheres to the metal, creating a barrier that inhibits further corrosion.<\/p>\n <\/p>\n <\/span><\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] All scuba cylinders have markings<\/strong><\/em> stamped on the top. Markings always include: Cylinders can have additional markings depending on the country where the tank was made: K-valve<\/strong><\/em>: This is a simple on off valve. Almost all modern scuba tanks have a K valve. On a tank with an\u00a0INT valve<\/strong><\/em>, the regulators\u2019 first stage is clamped on the valve. The o-ring is in the tank valve. INT (international) valves are often called Yoke valve. Adapters<\/strong><\/em> can be used to fit a DIN regulator on a Yoke valve and vice versa.<\/p>\n Most modern cylinders valves have a burst disk<\/strong><\/em> that protects the cylinder against damage from accidental overfilling. When the tankpressure becomes too high, the burst disk will rupture and pressure will be released.\u00a0<\/span><\/p>\n <\/span><\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,1_3,1_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” make_fullwidth=”on” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-k-valve-yoke-burstdisk.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.22.0″ text_font=”||||||||” background_color=”rgba(232,241,255,0.8)” background_layout=”light” custom_margin=”10px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”] As an industry standard, a visual inspection<\/strong><\/em> of the scuba cylinder should be done every year. Hydrostatic testing<\/em><\/strong> (pressure test) should be done out every 5 years, unless local regulations are different. If the cylinder is sanded to remove corrosion, if it suffered from impact or if it has been exposed to extreme heat, may also be a reason to carry out a Hydrostatic test.<\/p>\n <\/span><\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] The cylinder is immersed in water and pressurized. The cylinder is NOT filled with air but also with water.\u00a0 The test pressure is normally about 5\/3 of the working pressure. The cylinder will stretch slightly as it is pressurized.\u00a0<\/p>\n Next the pressure is released and the tester measures the cylinders permanent deformation. The permanent deformation of the cylinder should be within limits.<\/p>\n If the cylinder fails during the test it will not explode as it is filled with water.<\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-hydrostatic-testsystem.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” admin_label=”Class Details Area” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] Tanks that are used for Enriched Air \u2013 Nitrox normally have a yellow and green band around the cylinder that reads NITROX, or ENRICHED AIR. Modern tanks, valves, regulators and other equipment can be used with Enriched Air blends up to 40%. When using breathing gas that contains more than 40% oxygen, the equipment needs to be \u2018oxygen clean\u2019<\/strong><\/em>. The primary concern is the risk of cause a fire or explosion.<\/p>\n <\/p>\n <\/p>\n Open Circuit Scuba<\/strong><\/em>: This is the most commonly used system. The diver inhales from a compressed gas cylinder. When the diver exhales, breathing gas vents into the water and bubbles to the surface.<\/p>\n Closed-Circuit Rebreathers (CCRs)<\/strong><\/em>: The diver inhales from a bag (counterlung). The exhaled breath cycles through a system that removes waste carbon dioxide and replaces consumed oxygen, then returns it to the counterlung. There are no bubbles. Semi-Closed Rebreathers (SCRs)<\/strong><\/em>: The diver inhales from a bag (counterlung). The exhaled breath cycles through a system that removes waste carbon dioxide and returns it to the counterlung. It replaces consumed oxygen by letting a slow, steady flow of gas (Nitrox) into the counterlung. Excess gas is vented into the water, resulting in a slow, small stream of bubbles. <\/span><\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] The first stage<\/strong><\/em> reduces high pressure air from the tank to an intermediate pressure<\/strong><\/em>.\u00a0The intermediate pressure is always approximately 10 bar above ambient pressure.<\/p>\n The most simple type of first stage is an unbalanced piston<\/strong><\/em> first stage. Most divecenters are using unbalanced piston regulators as rental equipment. This system is \u201cunbalanced\u201d<\/strong><\/em> because high pressure from the tank is pushing on the pressure seat (red part in the picture), pushing the piston open. This means the tank pressure is affecting breathing resistance.<\/p>\n A balanced piston regulator<\/strong><\/em> works similar to an unbalanced regulator. Again, breathing from the second stage will reduce the force on the piston and the piston is pushed open by the combined force from the spring and the water. With this system however, the high pressure from the tank is not pushing on the piston so breathing resistance is not influenced by the tank pressure.<\/p>\n A Diaphragm first stage<\/strong><\/em> is also balanced. The working principle is not much different than that of a balanced piston regulator. Instead of a piston, it has a flexing diaphragm that pushes the valve open via a thin push rod.<\/p>\n Balanced piston and diaphragm systems are both found in top-of-the line regulators.<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,1_3,1_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” make_fullwidth=”on” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/padi-idc-divetheory-Unbalanced-piston.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”] Some regulator first stages are fitted with an Environmental seal<\/strong><\/em>. The environmental seal keeps water from entering the regulator. The water pressure pushes on a diaphragm so that the intermediate pressure still rises with the ambient pressure (depth). The second stage reduces the intermediate pressure that comes from the first stage to ambient pressure for breathing.<\/p>\n When the diver inhales, the water pushes a diaphragm<\/strong><\/em> inward. The diaphragm pushes on a lever<\/em><\/strong> that opens the valve<\/strong><\/em>. The diver can also push the diaphragm inward by pushing the purge button<\/strong><\/em>. When the diver exhales, a spring<\/strong><\/em> pushes the valve close.<\/p>\n <\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-second-stage-1.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] Second stages can also be balanced<\/strong><\/em>. Again, when the diver inhales, the water pushes a diaphragm inward and the diaphragm moves a lever. The lever moves the poppet assembly<\/strong><\/em> (yellow in the picture) and the valve opens.<\/p>\n When the diver exhales, the valve is closed by a spring. The valves in the first and second stages are Downstream valves<\/strong><\/em> and open with the air flow. The air will push the valve open and a spring is needed to keep it closed.<\/p>\n A malfunction will cause a continuous free flow of air rather than shutting off the air. This is known as a failsafe design<\/strong><\/em>.<\/p>\n In some very old regulators you could find a pilot valve<\/strong><\/em>. A pilot valve is a small valve that assists in opening the main valve. This construction is not used in modern regulators.<\/p>\n <\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] The modern BCD has three primary functions: 1) to let you float on the surface to rest or swim, 2) to allow you to adjust changes in your buoyancy while underwater, and 3) to act as the harness that holds the entire scuba system together on you.<\/p>\n Front mounted BCD’s<\/strong><\/em> or \u201chorse collar vest\u201d BCDs were the first true BCDs for divers. They are rarely used by modern recreational divers.<\/p>\n Back mounted BCD’s<\/strong><\/em> were the first style to integrate all the scuba The first\u00a0jacket style BCD’s<\/strong><\/em> came into the market to provide the single-unit advantage of back mounted BCD’s while redistributing the buoyancy for more balance, especially at the surface. Classic jacket style BCD’s really looked like a jacket but modern jacket BCD’s have adjustable shoulder straps for added comfort. Today this is the most common and popular configuration in recreational diving.<\/p>\n System BCD’s<\/strong><\/em> consist of interchangable components that you assemble for your needs. You can change out components for specific dive requirements. System BCD’s have a versatile harness and interchangeable BCD bladders as well as other options. System BCD’s are primarily back mount in design, though some configure to a jacket design when set up for recreational diving.<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,1_3,1_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” module_class=” et_pb_row_fullwidth” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” make_fullwidth=”on” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-Horseshoe-BCD2.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”] In very warm water, lycra skin suits<\/strong><\/em> can be used. They offer some protection against scratches and\u00a0abrasions but no temperature insulation.<\/p>\n Wet suits<\/strong><\/em> are made from neoprene. Wet suits allow water into the suit, but they trap the water. Your body heats this layer of water and the the neoprene insulation keeps it warm. Dry suits<\/strong><\/em> are made from neoprene or rubber coated nylon. The boots are part of the suit and the suit is fitted with neck- and wrist seals. Water doesn\u2019t enter the suit and a layer of air keeps the diver warm. Often undergarments are worn to increase the thickness of the air layer insulating the diver. Open bourdon tube gauges<\/strong> <\/em>contain a c-shaped shaped tube. Water enters the tubes and the increasing pressure causes the tube to straighten. This then moves the depth gauge needle.<\/p>\n Oil-filled bourdon tube gauges<\/strong><\/em> use a similar principle but here the tube sealed in an oil-filled housing.<\/p>\n Diaphragm depth gauges<\/strong><\/em> function by connecting a flexible diaphragm to a series of levers and gears that move the display needle. These are more accurate than bourdon tubes but more expensive.<\/p>\n Capillary depth gauges<\/strong><\/em> are a simple piece of clear tubing, sealed at one end and open at the other. Depth is indicated by how far the water enters the tube. They are inexpensive and reliable but are difficult to read when deeper than 10 metres. Electronic depth gauges use a transducer<\/strong><\/em>. This is an electronic component that converts pressure changes into an electric signal.<\/p>\n Transducers can also be found in divecomputers. Divecomputers not only register dive depth and dive time but also calculate the remaining no-decompression time, based on a mathematical model (algorithm<\/strong><\/em>).<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] The most common SPG\u2019s work on the same principle as the bourdon tube gauge. High pressure air enters a c\u2013shaped tube and causes it to straighten, causing the needle to move.<\/p>\n Electronic SPG\u2019s use a transducer similar to those in dive computers and are very accurate.<\/p>\n Electronic SPG\u2019s and computers can be attached to the high pressure hose or have a hose-less configuration with a transmitter<\/strong><\/em> attached to the first stage.<\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/spg.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,2_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||0px” custom_padding_tablet=”” custom_padding_phone=”|||0px” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/diving-compass.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][\/et_pb_column][et_pb_column type=”2_3″ _builder_version=”4.16″ custom_padding=”5%|5%|5%|5%” custom_padding_tablet=”” custom_padding_phone=”10%|||” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] The needle<\/strong><\/em> of the compass is a magnet so it always points to magnetic north. Weights can be carried on a weight belt or in pouches that are integrated in the BCD. The most important feature of a weight system is the quick release<\/strong> <\/em>system.<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”] A Surface Marker Buoy (SMB)<\/strong><\/em> can be deployed by a diver on the surface to warn boat traffic or it can be attached to a line and reel to be towed by a diver during a drift dive.<\/p>\n A Delayed Surface Marker Buoy (DSMB)\u00a0<\/strong><\/em>can be deployed from underwater. It has a closed construction that prevents air from leaking out and is equipped with an over-pressure valve that prevents the buoy from rupturing by expanding air when the buoy ascends to the surface.<\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/surface-marker-buoy.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][\/et_pb_section]\n","protected":false},"excerpt":{"rendered":" PADI IDC DIVE THEORYPADI dive theory – Equipment, is one of 5 subjects that will be tested on the PADI Instructor exam. We have made these materials available to help you to prepare for your PADI Instructor exam or PADI Divemaster exam. If you choose to do your PADI Divemaster course or PADI IDC with […]<\/p>\n","protected":false},"author":1,"featured_media":245142,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"class_list":["post-245141","page","type-page","status-publish","has-post-thumbnail","hentry"],"acf":[],"yoast_head":"\nEquipment<\/h2>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” hover_enabled=”0″ global_colors_info=”{}” sticky_enabled=”0″]
Scuba cylinders<\/h3>\n
– The metal type
– Hydrostatic test date
– Working pressure
– Manufacturer\u2019s name
\u00a0– Serial number<\/p>\n
– Thread Specification
– Empty weight
– Test pressure
– Regulatory authority, (for example U.S. Department of Transportation – DOT)
– Visual inspection sticker<\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-scubatanks-all_colors.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]Tank valves<\/h3>\n
J-valve<\/strong>:<\/strong><\/em> This valve closes the airflow when the tank pressure is low (20-40 bar). The diver needs to pull a lever to re-open the airflow. J-valves were used before the invention of submergable pressure gauges (SPG) and it is very unlikely to see it in modern scuba equipment.<\/p>\n
With a DIN valve <\/strong><\/em>(Deutsche Industrie Norm), the regulator first stage is screwed into the tank valve.
It has less chance on small leaks and can hold higher pressure (up to 300 bar).
For this reason it is preferred by technical divers.<\/p>\nK-Valve with INT connection and burst disk<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-DIN-valve.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” background_color=”rgba(232,241,255,0.8)” background_layout=”light” custom_margin=”10px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
K-Valve with DIN connection and adapter<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-J-valve.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” background_color=”rgba(232,241,255,0.8)” background_layout=”light” custom_margin=”10px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
J-Valve <\/h6>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]
Cylinder testing<\/h3>\n
The cylinder (outside and inside) is examined for damage and corrosion, the valve is removed and serviced and the threads checked for corrosion and damage.<\/p>\n<\/span>Enriched air equipment considerations<\/h3>\n
The markings are not used everywhere because local laws may require different markings.
The cylinder must also have a contents sticker identifying the oxygen percentage, fill date, maximum operating depth and the diver\u2019s name.<\/p>\n<\/h6>[\/et_pb_text][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-scuba-equipment.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ custom_margin=”||” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]
Three types of scuba<\/h3>\n
A computer monitors the partial pressure of the oxygen so that an ideal gas mix for whatever depth can be supplied to the diver. This greatly reduces the amount of nitrogen that the diver absorbs. Special training is required to use a Closed-Circuit Rebreather.<\/p>\n
Compared to a Closed-Circuit system, Semi-Closed Rebreathers are technically less complicated but still require special training before use.<\/p>\nOpen circuit regulators – First stage<\/h3>\n
When the diver inhales from the second stage, pressure in the two main chambers is reduced. The piston is pushed to the \u201copen\u201d position by the main spring and the water pressure. High pressure air flows into the main chambers and pressure builds up untill intermediate pressure is reached. At this point, the force pushing the piston close becomes larger than the force of the spring and the water and the piston is pushed back to the \u201cclosed\u201d position.<\/p>\nUnbalanced Piston<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-Balanced-piston.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
Balanced Piston<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-Balanced-diaphragm.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
Balanced Diaphragm<\/h6>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,2_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||0px” custom_padding_tablet=”” custom_padding_phone=”|||0px” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-Environmental-seal.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][\/et_pb_column][et_pb_column type=”2_3″ _builder_version=”4.16″ custom_padding=”5%|5%|5%|5%” custom_padding_tablet=”” custom_padding_phone=”10%|||” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]
The main advantage of an environmental seal is that the regulator is less prone to freezing in very cold water.
The picture shows the same regulator with environmental seal (top) and without (bottom).<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” width=”100%” max_width=”100%” module_alignment=”left” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”3_5,2_5″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”3_5″ _builder_version=”4.16″ custom_padding=”5%||5%|5%” custom_padding_phone=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]Open circuit regulators \u2013 Second stage<\/h3>\n
In closed position, intermediate pressure air flows into a balancing chamber<\/strong><\/em>\u00a0(red in the picture) and helps to push the valve closed. This reduces the \u2018cracking effort\u2019<\/strong><\/em> \u2013 the initial force needed to open the valve when the diver breathes in.<\/p>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_5″ _builder_version=”4.16″ custom_padding=”|0px||5%” custom_padding_phone=”10%|||0px” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-balanced-second-stage.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]Other features<\/h3>\n
BCD\u2019s<\/h3>\n
components into a single package. A primary complaint among recreational divers is the
tendency for back mounted BCD’s to float you face forward at the surface. Most cave divers and tec divers find this configuration optimal for their purposes. Tec BCD’s of this type are commonly referred to as \u201cwings,\u201d<\/p>\nHorseshoe BCD<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-wing-BCD2.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
Back mounted ‘wing’ BCD<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-System-BCD2.jpg” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ global_colors_info=”{}”][\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]
System BCD<\/h6>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]
Exposure suits<\/h3>\n
If your suit doesn\u2019t fit well, cold water can circulate into the suit and displace the warmed water. This is why a snug, proper fit is important.<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,2_3″ use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.16″ custom_padding=”|||0px” custom_padding_tablet=”” custom_padding_phone=”|||0px” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_image src=”https:\/\/asiascubainstructors.com\/wp-content\/uploads\/2020\/04\/PADI-IDC-theory-dry-suits.jpg” force_fullwidth=”on” align_tablet=”center” align_phone=”” align_last_edited=”on|desktop” _builder_version=”4.16″ animation_style=”fade” animation_delay=”500ms” global_colors_info=”{}”] [\/et_pb_image][et_pb_text _builder_version=”4.16″ text_font=”||||||||” custom_margin=”-50px|5%||5%” custom_padding=”10px||” global_colors_info=”{}”]Nylon and neoprene dry suits<\/h6>[\/et_pb_text][\/et_pb_column][et_pb_column type=”2_3″ _builder_version=”4.16″ custom_padding=”5%|5%|5%|5%” custom_padding_tablet=”” custom_padding_phone=”10%|||” custom_padding_last_edited=”on|desktop” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]
The seals have a conical shape and can be trimmed to the right size for proper fit.
Because dry suits hold air they are equipped with an inflator that is connected to a low pressure inflator hose. The diver mainly uses the dry suit inflator<\/strong> <\/em>to adjust buoyancy during the dive. Failing to inflate the dry suit can cause a suit squeeze<\/strong><\/em>. Diving with a dry suit requires additional training.<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]Depth gauges<\/h3>\n
Capillary depth gauges are suitable for altitude diving because at altitude, they will show the theoretical depths<\/strong><\/em> instead of actual depths.<\/p>\nSubmersible Pressure Gauge (SPG)<\/h3>\n
Compasses<\/h3>\n
Diving compasses are oil-filled so the housing can withstands the pressure, this also dampens the needle movement for easier reading. A straight line on the compass indicates the direction of travel and is called the lubberline<\/strong><\/em>. The course is set by turning the bezel<\/strong><\/em> so that the markings line up with the north arrow.
Electronic compasses are generally integrated into dive computers<\/p>[\/et_pb_text][et_pb_divider show_divider=”off” _builder_version=”4.16″ global_colors_info=”{}”] [\/et_pb_divider][\/et_pb_column][\/et_pb_row][et_pb_row use_custom_gutter=”on” gutter_width=”1″ make_equal=”on” _builder_version=”4.16″ background_size=”initial” background_position=”top_left” background_repeat=”repeat” max_width=”100%” module_alignment=”center” custom_padding=”50px|0px|0px|0px|false|false” use_custom_width=”on” width_unit=”off” custom_width_percent=”100%” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.16″ custom_padding=”|5%||5%” custom_padding_phone=”|5%||5%” global_colors_info=”{}” custom_padding__hover=”|||”][et_pb_text _builder_version=”4.27.4″ _module_preset=”a1d2168b-3d52-423f-b18a-f3a73e7ffb50″ max_width_last_edited=”off|desktop” global_colors_info=”{}”]Weight systems<\/h3>\n
Surface Marker Buoys<\/h3>\n