IRBs are made of rubber and consist of 4 inflatable tubes - 2 side tubes, a bow tube and a keelson tube. This specific feature coupled with the obvious fact that they are used in the water, has coined the term "rubber duck" or simply "duck" to describe an IRB. Typically the rubber is coloured a shade of red termed "Rescue Red" although a particular make of craft manufactured by 'Arancia' come in a shade of orange. They have a rigid floor piece and a rigid transom for fitting an outboard motor (usually 25 hp). This motor is capable of providing a maximum drive speed of between 25-30 knots on flat water. 2-Stroke fuel is stored in a flexible fuel bladder and is secured by 4 clips to the floor in the bow. An IRB is crewed by two people - an IRB Operator/Driver and an IRB Crewman. The Operator sits on the lower half of the port side pontoon where he operates the outboard motor to control the boat. He has foot straps to help him stay in the boat. His left hand can hold on to a strap on the port side pontoon and his right hand operates the outboard motor by means of a tiller arm and throttle. The Crewman sits on the upper half of the starboard side pontoon. A handle is attached by a rope to the nose of the boat for him to hold with his left hand, while his right hand may hold a strap attached to the starboard pontoon. He balances the boat and allows it to go over large waves before they break without flipping. He also assists when going through a breaking wave, commonly referred to as "punching-through". Two foot straps are available for his feet.
Prior to the start of a patrol, it is the driver's responsibility to ensure the craft is correctly set up and ready for patrolling duties. Typically this will involve inflating the crafts 4 pontoons to the correct pressure with a hand/foot or electric pump. The motor is test run in a tank of fresh water to check full function and reliability before installation to the transom. The fuel bladder is filled and installed along with a tow rope, rescue tube, 2 oars, and a blunt point knife as minimum. A check list is then filled in by the driver, after which the IRB may be signed on for patrol by radioing "Surf Command". At this point other patrol members assist to move the craft to a suitable launching position on the beach. This is usually a location outside of the safe swimming area defined by the patrol flags. Where applicable the boat maybe towed onto the beach by way of a tractor or small jeep and trailer.
When performing a rescue, the driver must negotiate large surf breaks and possibly obstacles such as rocks or other swimmers to reach the patient. The crewman helps the driver by keeping a lookout for the patient and hazards. He is also instrumental in keeping the IRB balanced when crossing surf breaks and turning rapidly. The crewman is also primarily responsible for bringing the patient on board, often during extremely dangerous and rapidly changing conditions, and looking after their welfare while at sea.
The crew of an IRB can communicate with the shore through various accepted hand signals or through modern waterproof radios which are becoming more popular.
During a patrol an IRB will be left on the beach by the waters edge at all times ready for action. On a busy day an IRB may be permanently out the back checking on swimmers.
On conclusion of the patrol, it is imperative the IRB is correctly packed up and stored to ensure it is ready for use by the next patrol. This is also the responsibility of the driver, who will usually start by radioing surf command and signing the IRB off for the day. This may involve reporting any rescues as well as how many people are still on the beach and in the water. Once the IRB has been signed off, the boat is taken up to the club where the motor is removed and run in a tank of fresh water for approximately 10 minutes. This clears the remaining salt water still in the cooling system, and allows for a quick check over of important parts of the motor. At the same time the IRB is emptied of oars, fuel tank, tube etc. The IRB will require a thorough hose down to remove sand, salt and shell grit, on and inside the boat. Standing the boat upright against a wall allows the water to fall down and out of the boat taking with it these unwanted particles. The boat is then returned to the trailer and the 4 pontoons are allowed to semi-deflate, to prevent over-stretching of the seams and rubber. The driver will fill in a checklist and report any faults, problems or issues to the club mechanic before storing the craft and motor. He will also report weather conditions and rescues performed for the day.