6"/53 caliber gun 6"/53 caliber gun The 6"/53 caliber gun (spoken "six-inch-fifty-three-caliber") formed the main battery of some United States Navy light cruisers and three US submarines built during the 1920s. United States naval gun terminology indicates the gun fired a projectile 6 inches (15 cm) in diameter, and the barrel was 53 calibers long (barrel length is 6 inch x 53 = 318 inches or 8 meters.) The gun with side swing Welin breech block and Smith-Asbury mechanism weighed about 10 tonnes and used a silk bag containing 44-pounds (20 kg) of smokeless powder to give a 105-pound (47.6 kg) projectile a
Standard person patients to radiation. According to the International Commission on Radiological Protection's 1974 definition, “Reference man is defined as being between 20-30 years of age, weighing 70 kg, is 170 cm in height, and lives in a climate with an average temperature of from 10°C to 20°C. He is a Caucasian and is a Western European or North American in habitat and custom.” Standard person The standard person or reference person is a theoretical individual that has perfectly "normal" characteristics. This model is used for much research into radiation safety. For many years, the standard person was called reference man because