A waterproof hearing aid, a tree harvesting vehicle for sustainable forestry, and a self inflating life jacket designed for safer free diving, have been announced New Zealand finalist designs in the annual James Dyson Award.

The prestigious international design award recognises the next generation of emerging Kiwi product designers who have developed inventions that are innovative and inspire solutions to everyday problems.

Revival Vest is a life jacket for divers, designed to recognise physiological changes in the wearer - such as drowning - to self inflate. Made from smart fabric technology capable of monitoring respiration, the vest detects changes in the diver's chest circumference, evident in divers experiencing breathing difficulty. If the wearer blacks out, the body becomes limp and the vest is triggered to inflate.

Its designer, 22 year old Victoria University graduate, James McNab of Tauranga, says his design was motivated by the death of a friend from a shallow-water blackout during free diving.

"With little or no safety equipment available to free divers, shallow-water blackout is something that can happen to even the most experienced divers and can occur without warning," says McNab.

David Lovegrove, the Award's head judge and professional member of the Designers Institute of NZ, says McNab's product, and the two other finalist products are diverse, yet they all demonstrate the design principles of the award's founder Sir James Dyson; to create commercially viable products that solve a problem.

The second finalist design - PressureAID -is a waterproof ear device for the hearing impaired, which aims to improve sound and give children and adults an opportunity to enter the water and enjoy swimming and other water sport.

Nick Marks, a 23 year old designer from Torbay, Auckland, says his design was inspired by his frustration in being unable to participate in water activities, in which water would enter his inner ear through grommets and cause an infection.

Marks says his product is designed to be worn inside the ears, and works when the wearer submerges their head in water, causing a bubble inside the device to compress, which then expands an ear piece membrane, creating a water-tight seal in the ear canal and preventing water from entering the canal.

"Because the device is worn just inside the ears like small headphones, they don't look like conventional hearing aids which aren't discreet. As a kid, I was bullied for wearing the old fashioned aids, so in the end I chose not to wear them and make-do with limited sound," says Marks.

Of the Massey University graduate's entry, David Lovegrove says this idea could improve people's lives.

"His design could also break down the stigma of wearing hearing aids due to its decorative effect and aesthetic appeal. The product will appeal not only to older adults who could wear the device in the shower, but for children prone to ear infections."

The third finalist product, Axolotyl, is a forestry tree harvesting machine, designed to cut and separate tree trunks, branches and needles on site, and return its nutrients to the ground for natural regeneration. Current harvesting methods require return visits to a forest, causing soil compaction and damage to surrounding trees.

Nick Ross, an industrial design graduate from Massey University says in one single operation, Axolotl cuts a selected tree at ground level, avoiding exposed stumps. It then feeds the tree into its body where it is separated. The needles are returned to enrich the soil, while the branches are bundled into a "bio-log" that can be easily collected when collecting the trunk, and used instantly as an alternative energy fuel. This technique seizes the traditional way of harvesting and points the future of tree harvesting in an environmentally friendly and sustainable direction.

Named after the endangered Mexican walking fish, Axolotyl's design was inspired by Ross seeing increasing degradation of forests through pollution.

The head judge said Axolotyl is a well presented and researched concept, and the designer shows talent at translating ideas into a well resolved product. He was encouraged to see sustainability was a core motivation in the product's development, and during the design process, the designer had consulted globally, manufacturers of other harvesting machinery.

"The product could make way for a new sustainable model in the forest industry," says Lovegrove.

The national winner will travel to the UK and meet with London's top product and design companies. They will earn a $3000 cash prize for travel, plus a fee package from the Intellectual Property Office of NZ (IPONZ), $3000 of legal fees from Farry.Co and a Dyson vacuum cleaner.

Now in the twelfth year, the James Dyson Award is open to final year tertiary students studying in the areas of design, technology or engineering, and to graduates in these areas who are in their first four years of work.

Established in 2001 by Avery Robinson, the distributors of Dyson in New Zealand, the James Dyson Award is held in association with British Council New Zealand, The Designers Institute, Farry.Co Law, IPONZ and The People's wine to recognise and reward up and coming Kiwi designers with product design ideas that best demonstrate innovative and inspiring solutions to everyday problems.

Fellow judge, Ingrid Leary from British Council New Zealand, says the short listed three are examples of Kiwi ingenuity at its best.

"The selected three show common sense solutions to everyday problems which will have resonance with New Zealanders and their water-loving lifestyles, as well as the forestry industry. It's also promising to know all three products have global appeal, and we're confident the designs will impress the British design companies our winner will have an opportunity to meet this year," says Leary.

Says James Dyson, engineer and inventor of the Dyson vacuum cleaner: "Experimentation and creativity need to be cultivated amongst young designers if we are to see future innovations emerge. This award is about giving the next generation of engineers and designers a head start."

Ten New Zealand entries, including the three national finalists, will progress to online judging in the international James Dyson Award competition. The global James Dyson Award winner will be announced in November 2012 and together with their university, they will win a total prize fund of �20,000 or local currency equivalent.

The James Dyson Award is supported by the James Dyson Foundation (JDF), a registered charity whose aim is to inspire and excite young people about design engineering.

The winning New Zealand entry will be unveiled at a ceremony to be held in Auckland on Thursday, 16 August. Entries can be viewed on www.jamesdysonaward.org