D24 Establish and maintain the dimensional control of construction and installation projects

D24.1 Establish and set out dimensional controls

Performance Criteria - this involves being able to...
(a) obtain available survey information, check that it is up to date and accurate and resolve any problems
(b) correlate and interpret information on construction and installation which is relevant to the setting-out of the project
(c) identify variations between the specified and the actual site dimensions, record them accurately and circulate them to decision makers
(d) identify and select appropriate grid systems to be used on the project
(e) set out reference markers which are suitably placed and accurate
(f) set secure reference points which are accurate, identified clearly and protected from movement or removal
(g) develop an observation scheme which meets the specified accuracy criteria
(h) select and maintain measuring and recording equipment which meets the specified accuracy criteria
(i) record any setting out information which may be of later use, and store it securely so that it is available when needed / The Range...
[1] Problems:
• unclear and missing information;
• inconsistencies between documents;
• errors
[2] Setting out information:
• dimensions;
• locations;
• levels (including inaccuracies and deviations);
• off-site manufacture, on-site assembly;
• required precision and tolerance
[3] Variations:
• boundaries;
• levels;
• locations
[4] Grid systems:
• national grid;
• local grid;
• lower case grid;
• site grid;
• structural grid
[5] Reference markers:
• ground stations;
• base lines;
• benchmarks;
• elevated target positions
[6] Observation scheme:
• graphical;
• measured;
• instrumental
[7] Measuring and recording equipment:
• mechanical;
• optical;
• electronic;
• field book;
• global positioning system


D24 Establish and maintain the dimensional control of construction and installation projects

D24.1 Establish and set out dimensional controls

The Evidence - performance and process
Product Evidence:
(1) Record(s) of checked and correlated survey and construction and installation information which includes resolved problems and variations (a,b,c) [1,2]
(2) Record(s) of selected grid systems and setting out reference markers (d,e,f) [4,5]
(3) Record(s) of setting-out procedures which include observation scheme, maintained measuring and recording equipment and setting-out information (g,h,i) [6,7]
(4) Record(s) of setting out (i) [7]
Process Evidence:
None applicable / The Evidence - knowledge and understanding
(1) How do you obtain available survey information and check that survey information is up to date and accurate? (application) (a) [1]
(2) How and why do you resolve any problems with survey information? (synthesis) (a) [1]
(3) How do you record variations between the specified and the actual site dimensions? (application) (c) [2]
(4) How do you record and store any setting out information which may be of later use? (application) (i) [2]
(5) How do you interpret information on construction and installation relevant to the setting-out of the project? (analysis) (b) [2]
(6) How and why do you correlate information on construction and installation relevant to the setting-out of the project? (synthesis) (b) [2]
(7) What do you identify as variations between the specified and the actual site dimensions? (understanding) (c) [3]
(8) Which grid systems do you identify as appropriate to be used on the project? (understanding) (d) [4]
(9) How and why do you select appropriate grid systems to be used on the project? (evaluation) (d) [4]
(10) How do you set out reference markers which are suitably placed and accurate? (application) (e) [5]
(11) How do you set secure reference points which are accurate, identified clearly and protected from movement or removal? (application) (f) [5]
(12) How and why do you develop an observation scheme? (synthesis) (g) [6]
(13) How do you maintain measuring and recording equipment? (application) (h) [7]
(14) How and why do you select measuring and recording equipment? (evaluation) (h) [7]