The phrase "as a third area" is correct and usable in written English.
It can be used when discussing multiple areas or categories, indicating an additional one beyond the first two mentioned.
Example: "In our analysis, we identified two primary areas of concern, and we will also explore the implications of climate change as a third area."
Alternatives: "as an additional category" or "as a supplementary area".
He also noted Microsoft's recent work in devops as a third area the company has recently focused on and plans to invest more in going forward.
Regarding the context as a third area for future research, we emphasize that existing network structures act as both opportunities and constraints to the creation of new ties (Nebus 2006).
Time, space and resources to enable adolescent participation emerged as a third area of need, followed by limited input into programme design and evaluation.
Thus far, its primary focus has been gaming, with 360-degree videos emerging as a second area of interest for some developers.
We have added personal goals as a ninth area to explicitly validate the importance of work life balance to long-term academic career success in BBS.
Even in eastern Arkansas, whose aquifers are fed by the Mississippi River, overuse has prompted state officials to designate a second area as critical because of scarce groundwater.
As a third priority area, the implementation of technological measures was identified.
The accumulating evidence of NDM-1 from the Balkan area could suggest a possible multifocal spread of this enzyme, with the Balkans as a possible second area of endemicity, in addition to the Indian subcontinent, and prompts for widespread epidemiologic surveillance.
The city is classed as a second-tier area under the government's anti-extremism Prevent strategy - which indicates a higher risk of extremism in the city.
Some sources also recognise the South West Peak (near Macclesfield) as a third type of area, with intermediate characteristics.
The rules designated part of the steps as a "First Amendment assembly area" and placed limits on the size of signs and other objects allowed on the steps.
