diff --git a/Manuals/FDS_User_Guide/FDS_User_Guide.tex b/Manuals/FDS_User_Guide/FDS_User_Guide.tex
index fcd0221a835..d60635c7b32 100644
--- a/Manuals/FDS_User_Guide/FDS_User_Guide.tex
+++ b/Manuals/FDS_User_Guide/FDS_User_Guide.tex
@@ -799,7 +799,7 @@ \section{Concatenating Input Files}
 \begin{lstlisting}
 &CATF OTHER_FILES='file_1.txt','file_2.txt' /
 \end{lstlisting}
-adds the contents of the two listed files into the current input file. Up to 20 files can be listed on one {\ct CATF} line, and multiple {\ct CATF} lines can be included in the input file. After reading the input file, FDS creates a new input file, {\ct CHID\_cat.fds}, and then runs the case.
+adds the contents of the two listed files into the current input file. The contents of the other files will be inserted at the location of each respective {\ct CATF} line in the input file. Up to 20 files can be listed on one {\ct CATF} line, and multiple {\ct CATF} lines can be included in the input file. After reading the input file, FDS creates a new input file, {\ct CHID\_cat.fds}, and then runs the case.
 
 When using this feature, limit the number of characters per line in both the original and added input files to 400.
 
diff --git a/Source/read.f90 b/Source/read.f90
index 33d38e493a6..521ec0c7987 100644
--- a/Source/read.f90
+++ b/Source/read.f90
@@ -330,39 +330,33 @@ SUBROUTINE READ_CATF
    ENDIF
 ENDIF
 
-! Load CHID file into LU_CATF:
-
-CALL COPY_FILE_TO_CAT(LU_INPUT,LU_CATF,0)
-
 IF (N_MPI_PROCESSES > 1) CALL MPI_BARRIER(MPI_COMM_WORLD,IERR)
 
 ! One &CATF line by one add the corresponding OTHER_FILES into LU_CATF:
 
 REWIND(LU_INPUT) ; INPUT_FILE_LINE_NUMBER = 0
-TFI=0
-COPY_OFILES_LOOP: DO
-   CALL CHECKREAD('CATF',LU_INPUT,IOS)  ; IF (STOP_STATUS==SETUP_STOP) RETURN
-   IF (IOS==1) EXIT COPY_OFILES_LOOP
+COPY_OFILES_LOOP: DO TFI=1,N_CATF_LINES
+   CALL COPY_FILE_TO_CAT(LU_INPUT,LU_CATF,0)
    OTHER_FILES(:) = 'null'
    READ(LU_INPUT,NML=CATF,END=13,ERR=14,IOSTAT=IOS)
    14 IF (IOS>0) THEN ; CALL SHUTDOWN('ERROR(101): Problem with CATF line.') ; RETURN ; ENDIF
    ! OPEN and copy other files into LU_CATF:
    OFI=0
    CPY_LOOP: DO
-      TFI = TFI + 1
       OFI = OFI + 1
       IF(TRIM(OTHER_FILES(OFI))=='null') EXIT CPY_LOOP
       ! If it exists open it and copy its contents without the &HEAD line (if any) up to the first &TAIL /
       ! appearance or the EOF.
       OPEN(LU_CATF2,FILE=TRIM(OTHER_FILES(OFI)),ACTION='READ')
       IF (MY_RANK==0) THEN
-         IF (TFI>1) WRITE(LU_CATF,'(A)')
+         IF (OFI>1) WRITE(LU_CATF,'(A)')
          WRITE(LU_CATF,'(A)')'# Start of file '//TRIM(OTHER_FILES(OFI))//' :'
       ENDIF
       CALL COPY_FILE_TO_CAT(LU_CATF2,LU_CATF,OFI)
       CLOSE(LU_CATF2)
    ENDDO CPY_LOOP
 ENDDO COPY_OFILES_LOOP
+CALL COPY_FILE_TO_CAT(LU_INPUT,LU_CATF,0)
 13 REWIND(LU_INPUT) ; INPUT_FILE_LINE_NUMBER = 0
 
 IF (N_MPI_PROCESSES > 1) CALL MPI_BARRIER(MPI_COMM_WORLD,IERR)
@@ -422,9 +416,11 @@ SUBROUTINE COPY_FILE_TO_CAT(LU_INFILE,LU_OUTFILE,FILENUM)
    ! Advancing READ:
 11 CONTINUE
    BACKSPACE(LU_INFILE); READ(LU_INFILE,'(A)') BUFFER2
-   IF (BUFFER2(1:5)=='&HEAD') CYCLE COPY_IFILE_LOOP
-   IF (BUFFER2(1:5)=='&CATF') CYCLE COPY_IFILE_LOOP
-   IF (BUFFER2(1:5)=='&TAIL') EXIT COPY_IFILE_LOOP ! Do not copy the tail line to LU_CATF
+   IF (BUFFER2(1:6)=='&HEAD ') CYCLE COPY_IFILE_LOOP
+   IF (BUFFER2(1:6)=='&CATF ') THEN
+      BACKSPACE(LU_INFILE); EXIT COPY_IFILE_LOOP
+   ENDIF
+   IF (BUFFER2(1:6)=='&TAIL ') EXIT COPY_IFILE_LOOP ! Do not copy the tail line to LU_CATF
    IF(MY_RANK==0) WRITE(LU_OUTFILE,'(A)') TRIM(BUFFER2)
 ENDDO COPY_IFILE_LOOP
 10 RETURN