11 Deliverables

NOTE 1 Deliverables provide the client with an understanding of the survey accuracy/confidence levels, methodologies used together with any cautionary advice notes/limitations.

NOTE 2 Survey data can be presented in a variety of outputs, such as CAD, GIS or BIM file formats, and/or in other project specific deliverable. The practitioner should agree with the client the format and media for file transfer.

11.1 Report

NOTE 1 The addition of a report affords the opportunity to outline the survey methods used and the success or otherwise that the survey has been able to achieve. It allows the practitioner to define areas of conflict and areas where further survey work or verification might be needed.

NOTE 2 The format for presenting this information may be textual (tabular or otherwise), photographic, planimetric, or graphic.

NOTE 3 A report can consist of a separate document or can be featured within CAD/GIS/BIM deliverables.

A report shall be produced and, as a minimum, contain the following:

a) a description of the survey project requirements and defined survey area;
b) a list of the detection methodologies used during the survey;
c) survey outcomes including:
- 1) planimetric information (see 11.2);
- 2) metadata (see 11.3);
- 3) a description of how successful each detection methodology proved to be and a plan showing any areas where these detection methodologies were not successful;
- 4) a list of any utilities that would have been expected to be present that were not detectable using these detection methodologies;
- 5) a list of buried features and obstructions other than utilities detected during the execution of the survey (see 11.5);
- 6)plans showing all areas of conflict between record information, site information and detected utilities;
- NOTE Photographs should be provided, where available.
- 7) for a verification survey, the verification deliverable (see 11.6);
- 8) recommendations for any further survey work provided during the execution of the works.

11.2 Planimetric information

11.2.1 The planimetric information shall be in the form of one or a combination of CAD drawing, GIS or BIM model as agreed with the client.

11.2.2 Where the client does not prescribe a format for the deliverable, the output shall be in a 2D or 3D drawing in both its native digital form and as a paper drawing.

NOTE The drawing can be derived from a CAD, GIS or BIM environment.

11.2.3 Where the client does not prescribe a specific layer/model naming convention, line style and line weight, the CAD/GIS/BIM drawing layers, model names and colour coding shall be in accordance with TSA's The essential guide to utility surveys – Detailed guidance notes for specifying a utility survey [NR1].

11.2.4 Metadata and any attribute data obtained shall be associated with its related CAD/GIS/BIM objects.

NOTE It is important that the same layers, colours and line weights are featured, irrespective of practitioner. This assists the client in becoming familiar with the conventions of this PAS.

11.2.5 Where abbreviations are used, the abbreviations shall be in accordance with TSA's The essential guide to utility surveys – Detailed guidance notes for specifying a utility survey [NR1].

11.2.6 A BIM deliverable shall be in accordance with the employer's information requirements (EIR) and the BIM execution plan (ВЕР) as specified in PAS 1192-2:2013, 5.3 and 7.2 respectively.

11.3 Metadata and attribute data

Metadata shall be provided as part of the deliverables with the following recorded as a minimum:

a) the date the information was obtained or where information is taken from records, the date shown on the record drawing;
b) utility type;
c) quality level of the utility segment in accordance with Table 1 (QL-A, QL-B1, QL-B1P, QL-B2, QL-B2P, QL-B3, QL-B3P, QL-B4, QL-C or QL-D);
d) detection method in accordance with Table 2 (M1, M1P, M2, M2P, МЗ, МЗР, М4 or M4P).

NOTE 1 In addition to the above metadata, attribute data at each utility location point may include the following:

a) utility owner;
b) electricity cables: depth (top of utility), low/high voltage;
c) communication cables: depth (top of utility), conventional cable/fibre optic;
d) gas: depth (top of utility), material, pressure (high pressure = HP, intermediate pressure = IP, medium pressure = MP, low pressure = LP);
e) water: depth (top of utility), material, diameter;
f) drainage pipes: depth to invert, use, material, internal dimensions (nominal);
g) manholes: depth to inverts, material, manhole chamber size, shaft size, shaft length, depth to landing stages, use [e.g. foul water (FW), storm water (SW) or combined water (CW)], cover size, cover weight (heavy, medium, light), cover shape, cover level, manhole internal schematic (sketch), coordinates of centre of cover;
h) inspection chambers: inspection chamber depth, number of ducts on each face of the inspection chamber, size of each duct, number of services in each duct, depth to crown of each duct;
i) oil pipelines: depth (top of utility), pressure, size, diameter.

NOTE 2 For further information on metadata, see metadata standards such as UK GEMINI 2 [7] and B5 EN ISO 19115 (series).

11.4 Unknown utilities

Any utility discovered that is unidentified during the execution of any of the survey types shall be marked as "unknown utility" in the deliverables.

11.5 Buried features and obstructions other than utilities

Where buried features and obstructions other than utilities are detected during the execution of any of the survey types, these shall be noted and reported in the deliverables.

11.6 Verification deliverable

11.6.1 Visible information shall be obtained and recorded from physical sighting of the exposed utility.

11.6.2 The measurement results obtained from exposing the utility shall be recorded on a trial pit/slit trench data sheet. This shall include as a minimum:

a) utility type;
b) utility depth (top of utility);
c) relative measurements to local detail for the location of the excavation;
d) geospatial location of the utility;
e) digital photographs taken of the location, open excavation and utility(s) as exposed;
f) a description and location plan of the excavation.

NOTE The following measurement results should also be obtained, where accessible:

a) utility diameter (external);
b) utility material;
c) note of adjacent utility markers, warning tapes and protection tiles or shields;
d) any accompanying utility apparatus such as pilot cables next to HV cabling.

11.7 Retention of survey data/records

All recorded and processed data, site notes, metadata, and intermediate stage processing files shall be retained for a minimum of five years, and shall be made available to the client on request.

NOTE A longer retention period may be required in the client's specification.

Annex A

(informative)

Accuracy

Figure A.1 illustrates the horizontal and vertical accuracies for QL-B1, QL-B1P, QL-B2, QL-B2P, QL-B3 and QL-B3P and how these are affected by depth. Each cone in the chart shows the envelope of expected accuracy. QL-B4 represents routes where detection was attempted but unsuccessful. Hence QL-B4 describes assumed routes and cannot be represented within the chart. The three sets of circles show examples of expected accuracies of detected utilities at 1,00 m, 1,50 m and 2,50 m deep.

Drainage invert levels are shown at manhole chambers with the manhole cover level. All other depths are shown to the top (crown) of the utility segment. Where the detection methods used detect depths to the centre or invert of the utility, these are adjusted by the practitioner to account for the variance.

Figure A.1 – Chart of horizontal and vertical accuracy for QL-B (informative)

Key

QL-B1 or QL-B1P, ±15% of depth or 0,15 m (whichever is greatest)

QL-B2 or QL-B2P, ±25% of depth or 0,25 m (whichever is greatest)

QL-B3 or QL-B3P, detection successful but no depth, horizontal ±0,50 m

NOTE The accuracy decreases beyond 2,00 m depth.

Utility with 63 mm diameter

Bibliography

Standards publications

For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

BS EN ISO 14688-1, Geotechnical investigation and testing – Identification and classification of soil – Part 1: Identification and description BS EN ISO 14689-1, Geotechnical investigation and testing – Identification and classification of rock – Part 1: Identification and description

BS EN ISO 19115 (series). Geographic information – Metadata

PAS 1192-2:2013, Specification for information management for the capital/delivery phase of construction projects using building information modelling

Other publications

[1] HEALTH AND SAFETY EXECUTIVE. Confined spaces – A brief guide to working safely. INDG258. Sudbury: HSE Books, 2013.

[2] GREAT BRITAIN. New Roads and Street Works Act 1991. London: The Stationery Office.

[3] HEALTH AND SAFETY EXECUTIVE. Avoiding danger from underground services. HSG47. Sudbury: HSE Books, 2014.

[4] GREAT BRITAIN. Traffic Management Act 2004. London: The Stationery Office.

[5] EUROPEAN TELECOMMUNICATIONS STANDARDS INSTITUTE. Electromagnetic compatibility and Radio spectrum Matters (ERM); Code of Practice in respect of the control, use and application of Ground Probing Radar (GPR) and Wall Probing Radar (WPR) systems and equipment, European Telecommunications Standards Institute, 2009.

[6] RICS GEOMATICS (MEASURED SURVEYS WORKING GROUP). Measured surveys of land, buildings and utilities 3rd edition specification and guidance note 2014. London: RICS, 2014.²⁾

[7] ASSOCIATION FOR GEOGRAPHIC INFORMATION. UK GEMINI, Specification for discovering metadata for geospatial data resources. v2.2. 2012, London: AGI, 2012.