Common practices performed by individuals / technicians in a field "[having ordinary skill in the art][ordinary_skill]" are NOT patentable--because these things are obvious and not-novel.  The [criteria] for patenting are that the invention MUST be at least:

 1. novel 
 2. non-obvious
 3. useful
 4. of an appropriate patentable subject matter

The specific claims written by the inventor(s) must be defended against thorough examination. The examiner is paid / tasked with finding faults in the patent application so it can be "disallowed". 

In order for the patent to be eventually "granted" to the inventor(s) the examiner must have examined the specification and claims and be unable to find serious fault that would prevent "allowance" of the claims.

That said the inventor can use _any language_ in their patent specification they desire so long as the _invention_ they claim ([patent claims][patent_claims]) at least meets all of the above criteria (and naturally the other baseline criteria for having a fully complete specification) [edited].

[ordinary_skill]: https://en.wikipedia.org/wiki/Person_having_ordinary_skill_in_the_art 

[criteria]: https://en.wikipedia.org/wiki/Patentability
[patent_claims]: https://en.wikipedia.org/wiki/Patent_claim