SQL & PL/SQL :: Compare Values In A Column Data

I have an requirement like below and would like to have SQL for that.

Source Table:

EMP_NO EMP_CODE
1 'A'
1 'D'
1 'E'
1 'F'

2 'S'
2 'A'
2 'W'
2 'Q'

3 'A'
3 'T'
3 'D'
3 'E'

4 'D'
4 'A'

I want to load only data which has EMP_CODE as A and doesn't have subsequent 'E' or 'F' in it. In the above source you can see EMP_NO 2 and 4 satisfy the condition and rest wont. So i want the output data like below.

Desired output:

EMP_NO EMP_CODE
2 'A'
4 'A'