Construction Activities As  the  crew  leader,  you  must  break  the  master activities   into   construction   activities.   The   work element  checklist,  contained  in  appendix  A  in  the NAVFAC   P-405   and   the   Seabee   Crewleader’s Handbook,  are   an   excellent   reference   for   the development of the construction activity list. A typical Naval Mobile Construction Battalion (NMCB) project might   contain   between   15   and   50   construction activities.  Construction  activity  numbers  are  usually four  digits.  The  first  two  digits  identify  the  master activity  and  the  second  two  digits  show  a  specific construction   activity   within   a   master   activity.   The number  also  includes  a  prefix  assigned  by  OPS  that identifies  the  specific  project.  Looking  at  the  list  of master  activities  example,  this  project  could  have  a construction  activity  for  “pre-fab  forms”  numbered 0312.   The   number   03   represents   master   activity “concrete  construction”  and  the  “1X”  distinguishes “concrete formwork” and the “2” represents “pre-fab forms”  from  the  order  of  precedence  in  that  master activity. Refer to the  Seabee  Crewleader’s  Handbook for the construction activities listing. MAN-DAY  ESTIMATES  AND  DURATIONS.— You  need  to  know  how  to  calculate  man-days  and duration   days   for   each   construction   activity.   The P-405  is  the  primary  reference  for  Seabee  man-day estimates.  The  P-405  lists  how  many  man-hours  it takes  to  do  one  unit  of  work.  The  size  of  the  unit  is also given. The quantity of work is divided by the unit size  and  multiplied  by  the  man-hours  required  to  do one unit. You then divide by 8 man-hours per man-day and   multiply   by   a   delay   factor   (DF).   Tasking, estimating,  and  reporting  are  always  done  in  8-hour man-days,  regardless  of  the  length  of  the  workday. Note the following formula: MDs = QTY Of WORK ÷ UNIT SIZE X MHRS PER UNIT ÷ 8  x DF For   example,   to   install   16,000   sf   of   1/2-inch drywall   over   wall   studs   would   require   how   many man-days? The equation should be as follows: MDs = 16,000 SF ÷ 1000 SF x 33 MHRS ÷ 8 = 66 x DF PRODUCTION   EFFICIENCY   FACTORS.— Production   efficiency   factors   are   the   first   step   in adjusting  man-day  estimates  based  on  your  unique circumstances.  The  intent  of  a  production  efficiency factor is to adjust for factors that will make you more or   less   productive   than   the   average   Seabee.   In calculating  a  production  efficiency  factor,  consider only those factors that affect the crew while on the job. Table  2-4  lists  eight  production  elements  in  the  far-left column.  You  need  to  consider  the  impact  of  each  of these  production  elements  on  each  activity  given  a specific  crew,  location,  equipment  condition,  and  so on. Then assign a production factor between 25 (low production)   and   100   (high   production)   for   each element.   A   production   factor   of   67   is   considered average.  Average  these  eight  factors  to  figure  your production efficiency factor (PEF). DELAY FACTORS.— Before you can adjust the man-day  estimate,  you  must  convert  the  production efficiency  factor  to  a  delay  factor  according  to  the graph  shown  in  figure  2-14.  You  can  find  the  delay factor by dividing 67 (the average production factor) by  the  production  efficiency  factor  (DF  =  67/63.6  = 1.05). (See table 2-4.) Using the delay factor of 1.05 you now can adjust the original man-day estimate as shown in the following equation: 66 x 1.05 = 69.3 or 70 MD This  mathematical  procedure  has  limitations.  If, for example, you were working outside in extremely bad  weather  and  all  other  factors  were  considered average  (weather  =  25,  all  others  =  67),  you  would obtain a production efficiency factor of 62 and a delay factor of 1.08. This 8 percent increase in the man-day estimate  would  not  adequately  compensate  for working in extreme weather. You are not limited to the method  of  delay  factors  in  the  P-405.  Use  common sense  when  impacted  by  extreme  circumstances. Come  up  with  what  you  feel  is  a  reasonable  delay factor and discuss it with your chain of command. You are   not   bound   by   either   the   delay   factors   or   the production  rates  in  the  P-405.  To  figure  man-day estimates,  you  can  use  your  experience  to  determine the logical production rates to use. Keep in mind that the delay factor is only used to determine the man-day estimate  for  a  particular  construction  activity.  Each activity  will  have  a  different  delay  factor.  All  other calculations use the availability factor. AVAILABILITY   FACTORS.   —Availability factors  take  into  account  that  Seabees  assigned  as direct labor are not available 100 percent of the time. Each  Naval  Construction  Brigade  provides  the availability  y  factors  for  planning  purposes.  Availability  y factors  are  sometimes  still  referred  to  as  site  efficiency factors.  These  factors  vary  between  0.75  for  main body sites to 0.85 for detail sites. Using the following equation,  you  can  determine  the  man-day  capability (MC) for the main body and each detail. 2-27