Swimming at the 1968 Summer Olympics – Women's 200 metre freestyle Swimming at the 1968 Summer Olympics – Women's 200 metre freestyle The women's 200 metre freestyle event at the 1968 Olympic Games took place between 21 and 22 October. This swimming event used freestyle swimming, which means that the method of the stroke is not regulated (unlike backstroke, breaststroke, and butterfly events). Nearly all swimmers use the front crawl or a variant of that stroke. Because an Olympic size swimming pool is 50 metres long, this race consisted of four lengths of the pool. Heat 1 Heat 2 Heat 3 Heat 4 Heat 5 Heat 6 Key: OR = Olympic
Swimming pool used to sanitise the water. Chemical disinfectants, such as chlorine (usually as a hypochlorite salt, such as calcium hypochlorite) and bromine, are commonly used to kill pathogens. If not properly maintained, chemical sanitation can produce high levels of disinfection byproducts. Sanitized swimming pool water can theoretically appear green if a certain amount of iron salts or copper chloride are present in the water. Acesulfame potassium has been used to estimate how much urine is discharged by swimmers into a pool. In a Canadian study it was estimated that swimmers had released 75 litres of urine into a large pool that