The light, 80 feet above high water mark can be seen 14 miles away at sea level, either white, red or green accordingly to the position of the observing ship; it is easily identified by the double-occulating nature of the light, eclipse for two seconds, light for two seconds, eclipse for two seconds and then darkness for fourteen seconds. Many visitors, however, will be most familiar with the lighthouse foghorn which sounds every fifteen seconds during periods of poor visibility.
Originally this lighthouse had a keeper and three assistants. The men were on duty for two months and then on leave for one month. There were always three men on duty at the lighthouse at any one time. Sadly, the lighthouse was automated in 1994 and we said goodbye to the keeper and his assistants. In spite of the presence of the lighthouse, the Needles have always constituted a danger to shipping - over the years many ships have floundered on or near these rocks.