TM 10-8415-209-10 TM 8415-10/2 2-3.  DOFFING THE CHEMICAL PROTECTIVE UNDERWEAR (CPU). WARNING The  following  doffing  procedure  is  to  be  used  only  when  you  have  not been  exposed  to  contamination.    For  decontamination  procedures,  see FM 3-5/FMFM 11-10. a. General.      These   procedures   should   be   performed   when   removing   the   CPU   in   an   uncontaminated environment.  Refer to FM 3-5/FMFM 11-10 for removing clothing items in a contaminated NBC environment. b. Perform the following steps: (1) Remove helmet and chemical protective helmet cover, if worn. (2) Remove chemical protective mask and hood (refer to Soldier's Manual STP 21-1-SMCT or Appendix A for specific chemical protective mask TM). 2-14