Final answer:
Live parts with voltages ranging from 50V to 1,000V should be guarded by being enclosed in non-conductive material, which is a safety measure to prevent electric shocks.
Step-by-step explanation:
Live parts operating at 50V to 1,000V nominal should be guarded by being enclosed in non-conductive material. This safety measure prevents direct contact with live parts, which can lead to electric shock or electrocution. Our bodies conduct electricity effectively due to the high water content, so it's crucial to prevent a pathway for electrical current that could result in serious injury or death. A common safety measure besides using non-conductive enclosures is the wearing of insulated shoes, which stops a pathway for electrons through the feet by providing large resistance. Moreover, other precautions such as using a Faraday cage can protect against stray electrical fields, ensuring a safe working environment.