It does require a "waste trap" such as a "P" type
YES, you do need a trap. Usually the bathtub drain is on the same sewer line as the nearby toilet.The smell from the toilet's discharge will sneak up through the bathtub's drain line without a trap ... not pleasant!.
Trap seal loss occurs when you have poor venting and as one fixture drains it creates negative pressure created and it pulls the trap seal (water) from another trap and allows sewer gases to enter the structure
Direct
Code there doesn't always require a 'P' trap to hold water and thus block sewer gases from backing into the house.
The sewer
To stop sewer gasses from being expelled from the sewer
The building code is most likely going to require a trap to prevent gases from backing up into the house. I know they had to put them in my home.
I don't understand this question However a sewer trap is always buried in the ground, so I cant see how it can be exposed.
You can easily find the main sanitary sewer trap by locating the fresh air inlet which is located no more then 4 feet behind the building house trap. It will be 1/2 the size of the main sewer but in no case less then 3" and 12" above grade min.
No you don't. The trap is inside the toilet.
Wastewater from your kitchen and bathroom is piped to a gully trap before emptying into the sewer. A gully trap is a basin in the ground with a water seal to prevent foul odours of the sewer reaching the surface. Gully traps are buried in the ground with the tops or surround raised above ground level to prevent ground water entering into the sewer.
the toilet overflows if either the building sewer, branch line in your sewer system or trap in your toilet gets clogged.