Non ASCII character

I have a function that cleans up NoN Ascii characaters but I came across this bad boy (┬╡)and when I try to run the function that does the cleaning of Non ASCII characters it prompts me for a replacement value for the word MARBLE?

Select clean_non_ascii('‘JOHNS TILE ┬╡& MARBLE INSTALLATION INC                         ‘') From Dual

The function looks like this


function  clean_non_ascii(input_str             in varchar2,
                          usetable              in number default 0,
                          use90                 in number default 0)

return varchar2 as

str VARCHAR2(100 BYTE);  --Extra 2 Bytes for ^
str60 VARCHAR2(70 BYTE); -- Extra 2 BYTES for ^
act number :=0;
cnt number :=0;
askey number :=0;
OUTPUT_STR VARCHAR2(90 BYTE);
OUTPUT_STR_60 VARCHAR2(60 BYTE);
err_code NUMBER;
err_msg VARCHAR2(200);  

  begin

      str:= '^'||TO_CHAR(INPUT_STR)||'^';
      cnt:=length(str);
      if length(cnt) = 0 then
        for i in 1 .. cnt loop
          askey :=0;
          select ascii(substr(str,i,1)) into askey
          from dual;
          if askey < 32 or askey >=127 then
            str := '^'||REPLACE(str, CHR(askey),'');
          end if;
        end loop;
        OUTPUT_STR := trim(ltrim(rtrim(trim(str),'^'),'^'));
      else
        OUTPUT_STR := INPUT_STR;
      end if;

      RETURN (OUTPUT_STR);

  end clean_non_ascii;