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¦.
Typhoid vaccine can prevent typhoid. 2 Typhoid vaccines. There are two vaccines to prevent typhoid. One is an inactivated (killed) vaccine gotten as a shot, and the other is live, attenuated (weakened) vaccine which is taken orally (by mouth).ive Typhoid Vaccine (Oral). 1  Should not be given to children younger than 6 years of age. 2  Four doses, given 2 days apart, are needed for protection. 3  The last dose should be given at least 1 week before travel to allow the vaccine time to work.