construction methods to be followed are decided. The engineer  determines  the  loads  that  the  supporting structural  members  will  be  required  to  bear  and designs  the  mechanical  systems.  such  as  heating. power.  lighting,  and  plumbing. As a crew member or a supervisor. you will find the construction drawings. the specifications. and the bill  of  material  your  main  sources  of  information during  the  construction  and  estimating  phases  of  the project. Drawings are commonly indexed so you can easily find the sheet you need. The drawing index is located on the cover sheet or sheet 1 of the set. They are divided into  eight  categories  and  appear  in  the  following  order: 1. Plot and vicinity 2.  Landscape  and  irrigation 3.  Architect 4.  Structural 5. Mechanical 6.  Plumbing 7. Electrical 8. Fire protection WORKING  SKETCHES A working sketch is a drawing made from the working drawings to express a tasking clearly and to provide a quick reference to job requirements. It is drawn to help show actual conditions on the job, what size pipe is to be installed, or where connections will be made. The sketch should show as much detail as possible  to  help  your  crew  during  installation  or troubleshooting. A working sketch will usually show the  work  you  want  your  crew  to  accomplish  in  a selected  area  and  will  provide  ready  reference  to jobsite  conditions. A crew should have a working sketch with them while working. It will show them how, what, where, and when things happen in the sequence of the job. Your first step in making a working sketch should be to draw the symbols that represent all the fixtures or equipment that is to be installed and locate them within the  room.  Try  to  draw  them  in  the  sequence  of installation and include measurements. The amount of detail you use in a working sketch will be determined by  the  crew’s  experience,  the  complexity  of  the systems involved, and the need for cooperation with other trades working on the jobsite. AS-BUILT DRAWINGS Upon the completion of a facility, the crew leader or project supervisor should provide marked prints that indicate any construction deviations. The information required  must  show  all  features  of  the  project  as actually, built. As-built drawings should be reviewed after they are completed. This review assures that all information appearing on the drawings shows the exact as-built conditions. From the as-built drawings, record drawings are prepared. These drawings are the original construction drawings, but they are corrected according to the as- built marked print. They then provide a permanent record   of   as-built   conditions.   The   final   record drawings must be kept up to date at all times. If this maintenance requires a change to the record drawing, then this information should be passed on and the record drawings updated. BLUEPRINT  LANGUAGE To understand the instructions and dimensions on a working drawing, you must be able to read and understand the language of the prints not only for your particular job but also for all the different phases. Plans, specifications, and details go together. It is impossible to use one successfully without the other. Never  overlook  a  reference  note  on  a  drawing.  The blueprints  contain  the  information  and  directions  that require you to do your part of the total job as planned. It is also important to follow all the instructions on a blueprint faithfully. Any deviation on your part may make  it  impossible  for  fellow  tradesmen  to  do  their work properly or successfully. To  read  blueprints,  you  must  understand  the meanings  of  all  devices,  such  as  various  lines, symbols, conventions, abbreviations, and methods of giving  dimensions  and  working  directions. TYPES AND WEIGHTS OF LINES FOUND ON DRAWINGS The types of lines the electrician should be able to read  and  understand  are  given  below.  In  figure  2-1 these lines are shown as they may appear on a drawing. Trim line: a light, continuous line along which the tracing is trimmed to square the sheet. Border line: a heavy, continuous line that outlines or borders the drawing. The drawing is complete within this lined border. 2-4