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.
The  first patent for a flushing water closet was issued to Alexander  Cummings in 1775, sixty years before Thomas Crapper was born.Thomas crapper was just a myth he didn't invent the tioletFrank Henrieta invented the toilet seat during the Italian Renaissance in 1634.he earliest patent I can find for a toilet bowl brush, # 160415, was granted to Moser in October of 1950.   Thomas Crapper did NOT invent the toilet bowl brush, although â¦ he did patent several other things, including the ballcock, which is part of a flush toilet.