Bridson grew up in Auckland, New Zealand. He went to Auckland Grammar School and became the Auckland swimmer of the decade. He won nine national men's swimming titles: the 100 yd freestyle in 1930, 1931, and 1932; the 220 yd freestyle in 1930, 1931, and 1932; and the 440 yd freestyle in 1929, 1930, and 1931.
At the 1930 British Empire Games in Hamilton, Ontario, he won silver medals for both the 400 yd and 1500 yd freestyle.
Bridson began his naval career in 1927 by joining the Royal Naval Volunteer Reserve in Auckland. He was commissioned in February 1928 and in April 1940 was mobilised for war and promoted to lieutenant commander. The following month he was sent to England to serve in the Royal Navy.
In England Bridson commanded HMT Walnut. Walnut was a Tree-class minesweeper belonging to a group of ten ships commanded by New Zealanders. For a year these ships were deployed as the 24th and 25th anti-submarine and minesweeping flotillas, protecting convoys on the east coast of Britain. They were often attacked by air and sea. Bridson received the Distinguished Service Cross for his performance during this time.
Bridson then commanded the newly built minesweeping trawler HMNZS Kiwi, commissioned at Greenock in October 1941. On New Year's Day Kiwi accompanied a convoy setting out from Greenock to cross the North Atlantic to Newfoundland. They encountered a severe storm which damaged the Kiwi. Bridson then sailed her to New Zealand.
Back in New Zealand, the Royal New Zealand Navy formed the Kiwi, together with Moa and Tui (Kiwi's two new minesweeping trawler sisters) and Matai (a converted merchant ship), into the 25th Minesweeping Flotilla. In December 1942 the flotilla set sail for deployment in the Solomon Islands.
On 14 January 1943 an American PT boat fired two torpedoes at Kiwi. It was a mistake but they missed. It angered the New Zealanders, though Bridson subsequently became friends with the PT commander.
Later the same month, in the late evening of 30 January, Bridson was senior officer while Kiwi jointly patrolled Guadalcanal Island with Moa. They detected the large Japanese submarine I-1. The submarine was over twice the size of the New Zealand boats, with a more powerful five-inch gun. The submarine surfaced so it could use its gun while the Kiwi attacked with depth charges. Kiwi then repeatedly rammed the submarine while firing point blank with its 4-inch gun. The Kiwi's fire capability was assisted by an unofficial 20-mm Oerlikon on its bow, which it came to possess at Noumea in exchange for two bottles of gin.
[Bridson] ...gave the order to ram. At the same time he thought he'd better let the engine room know what was going on. So he shouted down the voice pipe, "Stand by to ram." When the voice came back from the engine room, "What the hell do you mean by ram?" he replied, "I don't know. I've never done it before."
Eventually, chased by Moa, the I-1 stranded and sank on a reef. The Kiwi's searchlight operator, leading signalman Buchanan, was killed, and the Kiwi had to go back to New Zealand for repairs to her bow.
Bridson was awarded the Distinguished Service Order and the United States Navy Cross for this action.
In May 1944 he became acting commander in Dunedin. Six months later he was made commander in charge at Lyttelton and became also an aide de camp to the Governor-General of New Zealand. He remained in these positions until the 1946 demobilisation.
Bridson moved to Te Aroha with his wife and three children and worked as a partner in his hardware business. Late in the 1950s he became a farmer near Cambridge, where he died on 6 December 1972.