OSHA defines an excavation as any man-made cut, cavity, trench, or depression in the earths surface formed by earth removal. A trench is defined as a narrow underground excavation that is deeper than it is wide, and is no wider than 15 feet (4.5 meters). Dangers of Trenching and Excavation. Cave-ins pose the greatest risk and are much more likely than other excavationrelated accidents to result in worker fatalities.
How long does a typhoid shot last?   According to the CDC website, a booster dose is needed every 2 years for people who remain at risk.. The oral (live) vaccine lasts 5 years before another dose is neededâ¦.
Local Reactions. Shot sites can have swelling, redness and pain. Most often, these symptoms start within 24 hours of the shot. They most often last 2 to 3 days. With the DTaP vaccine, they can last up to 7 days. Fever. Fever with most vaccines begins within 24 hours and lasts 1 to 2 days.