Section 9: Laboratory tests on samples
55 General
Geotechnical laboratory testing should be carried out in accordance with BS EN 1997-1, BS EN 1997-2, NA to BS EN 1997-2 and, where not covered by these standards, the various other standards and methods recommended in Table 36 to Table 42. Other test methods might be required for more complex geotechnical structures (geotechnical category 3).
The programme of investigation should be designed:
- a) to classify the samples; and
- b) to obtain parameters relevant to the technical objectives of the investigation.
NOTE The test methods, analysis and interpretation of laboratory test results are not covered by this British Standard.
56 Roles and responsibilities
The laboratory should have an organizational structure with clearly defined responsibilities. The structure should be communicated to all staff including temporary workers. All staff should have experience and knowledge commensurate with their role.
The laboratory supervisor should manage the laboratory testing activities and have knowledge and experience of the laboratory systems of work including quality assurance, health and safety systems and the requirements for the tests. The laboratory supervisor should:
- organize and co-ordinate the work of staff;
- organize training, instruction and supervision;
- select the test methods to be available;
- ensure safe working practices;
- arrange health surveillance for employees, where required; and
- check the quality of sample delivered to the laboratory is suitable for the tests that have been scheduled (where the sample is not suitable, this should be reported to the geotechnical advisor).
Laboratory technicians should have suitable training for and experience of the particular tests they undertake.
57 Health and safety in laboratories
57.1 General
COMMENTARY ON 57.1
For general advice on health and safety in the laboratory, see the AGS General laboratory safety document [129] and also Annex A. Attention is drawn to the Health and Safety at Work Act 1974 [130].
The laboratory should have a safe system of working in place, which includes:
- risk assessments of each task and procedure that might cause harm to the laboratory staff, other persons or the environment (see HSE guidance documents14));
- a contingency plan to deal with foreseeable emergencies;
- documentation of the safe systems of work; and
- an auditing and monitoring system to ensure safe working.
57.2 Screening of samples containing hazardous substances
The geotechnical laboratory should be informed at an early stage of the ground investigation if samples are likely to contain hazardous substances (see Section 3). The laboratory should undertake a risk assessment and decide whether testing on the samples is safe and make any necessary changes to existing health and safety and test procedures.
NOTE 1 Additional health and safety precautions might be required relating to handling, transport and storage as well as the test procedures; any additional precautions might increase the costs.
Any samples that are known or suspected to contain asbestos or other particularly harmful substances should be labelled with the type(s) of harmful substance in the field (see 17.8, 17.9 and 19.2.5). Samples allocated for testing in a geotechnical laboratory should be screened for the presence of harmful substances by an appropriate laboratory prior to deciding if geotechnical testing should proceed. These test results should be supplied to the geotechnical advisor and laboratory manager. The laboratory manager should decide whether a sample is safe to carry out the required tests. The geotechnical advisor should then be informed as other samples might be substituted.
NOTE 2 The identification of a hazardous substance might require the use of different methods of sampling, sample container and storage conditions than those for geotechnical purposes (see BS 10175 for further recommendations).
The receipt of samples known to, or likely to, contain hazardous substances should be by agreement with the geotechnical laboratory. The samples labelled as containing or likely to contain hazardous substances should be stored in a separate part of the sample store that should be identified for this use (see 58.2).
NOTE 3 It is preferable that a geotechnical laboratory receives only those samples that are have been identified as suitable for testing.
57.3 Data recording, management and transfer
The laboratory should have a data management system that covers all aspects of sample, subsample, specimen and test data (see BS 8574).
NOTE Results are generally stored digitally and might be transferred to others using an industry standard digital data transfer format.