"designating them as" is a correct and usable phrase in written English.
You can use it to express the idea of labeling or classifying something or someone as something else. For example, "The school assigned student roles by designating them as captains and co-captains."
We secured an agreement with the state designating them as first responders".
Buildings must be at least 30 years old before the Landmarks Preservation Commission will even consider designating them as landmarks.
Long-term unpaid internships are illegal, but organisations get around the law by officially designating them as volunteer schemes.
Some people might be overtreated because their B.M.I. was above a line designating them as having a disease, even though they were healthy.
7): It is easy for demagogues to whip up intolerance, bigotry and fear of Islam and Muslims in the United States by designating them as the "other".
We need to make the gardens permanent — perhaps by designating them as parkland, entering into long-term leases or putting legal restrictions on the use of the land.
Many banks got rid of the riskier and more junior CDO tranches, because their own risk-management systems designated them as too dangerous.
Twelve others have been designated by President Bush as eligible for trial, and military officials have suggested that they are prepared to bring charges against dozens of other prisoners there should the president designate them as well.
From trailing the market by 16 points in the year before we designate them as inexpensive, they outperform in the next year by 3 points, a 19-point swing.
These birds are pests and government has designated them as such.
A bibliographer collected and edited ancient texts and designated them as classics.
