in   the   absence   of   sunlight   or   daylight,   the impregnation  treatment  should  remain  effective for  5  to  10  years  or  more. NOTE: Impregnated clothing is being phased out   and   will   be   replaced   with   the   chemical- protective  overgarment. Chemical-Protective Overgarment The chemical-protective overgarment consists of  two  pieces—a  smock  and  trousers  (fig.  6-9). The  smock  has  two  layers  of  materials:  inner (antigas)   and   outer   (modacrylic/nylon).   The smock   is   generously   cut   to   allow   complete freedom  of  movement.  It  has  a  large  front  flap pocket  for  gloves  and  so  forth  and  a  sleeve patch  where  you  can  place  detector  paper for  easy  visibility.  You  can  make  quick  and easy  adjustments  with  hook-and-pile  fasteners at  the  wrist  and  waist.  The  trousers  are  made of  the  same  two  layers  of  material  and  have suspender-type fittings located at the waist and across the shoulders. Hook-and-pile fasteners are located  at  the  base  of  each  leg  for  adjustment. Figure  6-9.-Chemical-protective  overgarment. The chemical-protective overgarment is issued in a  plastic  envelope  that  is  pressure  packed,  air evacuated, and heat sealed. It is then placed in a  polyethylene  bag  and  heat  sealed.  The  over- garment has a shelf life of 5 years when unopened. The  protective  overgarment  protects  against all CBR agents and is permeable to water vapor. Once removed from its protective envelope, it has a shelf life of 14 days in a nonchemical environ- ment.  If  it  is  opened  but  uncontaminated,  keep it  for  training  purposes.  Once  exposed  to  chemical contamination, the overgarment provides 6 hours of  continuous  protection,  after  which  it  should be  discarded. The following donning procedures include the use  of  the  chemical-protective  glove  set  and footwear   covers   (overboots): 1. 2. 3. 4. 5. 6. 7. 8. Don  the  trousers.  Tighten  the  waist  by using  the  hook-and-pile  fasteners. Bring  the  straps  over  the  shoulders  and cross them at the chest. Insert the straps into  the  belt  loops  and  secure  snugly. Don  the  parka. Secure the bottom of the parka with hook- and-pile straps. Raise the trouser legs. Don   the   chemical-protective   footwear cover  (see  fig.  6-10). a. b. c. d. e. f. g. Attach  tie  laces  (in  the  center)  to  the toe loop. Be sure the laces are even (see fig.  6-10,  view  1). Put   one   lace   through   A   and   one through  B  from  the  inside  to  the  out- side and pull until snug. Make sure the toe loop is over the top of your shoe (see fig.  6-10,  view  2). Put   one   lace   through   C   and   one through D (on the opposite side of the foot, crossing the instep) from inside to outside. Pull until snug (see fig. 6-10, view 3). Cross the laces over the instep. Thread   the   laces   through   A   and   B again,  from  inside  to  outside  (see  fig. 6-10,  view  4). Cross the laces over the instep again and pull them until snug. Wrap  the  laces  behind  the  ankle  and back to the front. Pull until snug and tie  securely  (see  fig.  6-10,  view  5). Pull  the  trouser  legs  down  over  the footwear covers and secure with the hook- and-pile fasteners. Don  the  mask. 6-18