For example, for the Gases under pressure hazard class, the hazard categories are Compressed gas, Liquefied gas, Refrigerated liquefied gas and Dissolved gas. These classes relate to the physical state of the gas when packaged and do not describe the degree of hazard.
1 In 1596, a flush toilet was invented and built for Queen Elizabeth I by her Godson, Sir John Harrington. 2  The first patent for the flushing toilet was issued to Alexander Cummings in 1775. 3  During the 1800s, people realized that poor sanitary conditions caused diseases.
Manual Dishwashers. The first dishwasher was invented in 1850 by Joel Houghton. The machine was wooden and had a hand-turned wheel. The wheel simply splashed water over the dishes in the machine.osted by Staff Writer in Dishwashers. ANSWER: The first commercially available power-moded dishwasher was invented by Josephine Cochrane in 1886. More Info: Dishwashers are one of the most common home appliances; however, many people do not know how these amazing machines transformed.