Behavioural sampling

Behavioural sampling was developed in the 1950s to overcome some of the problems associated with the LTI-rate. It applies statistical sampling techniques in observing deviations from accepted safe work practices and conditions (Rockwell, 1959 Tarrants, 1980). The aim is to prevent losses by reducing the frequency of such deviations. The basic principle of accident prevention is the same as in the fertiliser plant case of Chapter 4. In behavioural sampling, we are concerned with the behaviour of people rather than of technical processes. 

The measurement of SHE performance through behavioural sampling includes the following steps  

1 Identification of critical behaviour by analysing accident reports, safety instructions, inspection reports etc. 

Selection of behaviour to be included in the performance indicator and establishment of a checklist with operational definitions of each item. The selected items have to be easily observable and the distinction between safe and unsafe has to be clear. 

Inspections of the workplaces at randomly selected intervals to observe the items and whether the performance is correct or not. Plotting the safety performance index on a control chart. The safety performance index is defined as the percentage of the observed items that are judged as correct. 

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Altmann, J. (1974) Observational study of behaviour sampling methods. Behaviour 49, 227-267. 

At temperatures higher than 650°C the 0-FeAl phase is connected to the a-Fe(Al) phase field without phase boundary. To elucidate the effect of decreasing order with decreasing aluminium content on the oxidation behaviour, samples from the whole range of this phase with 5,10,15,20,25,30,40 and 48 at.% A1 were investigated in exposure experiments. 

The next step in the development of behavioural sampling took place in the 1970s (Komaki et ah, 1978). They based their work on behaviour theory (see Section 13.3) and introduced feedback to the workers as a consequence. (See Figure 18.1.) The rationale behind this scheme was to increase the immediate and positive consequences of safe behaviour. After a first secret measurement of the baseline, the results were presented to the... 

Figure 18.1 Application of behavioural sampling in controlling performance. Source Komaki et ah, 1978.

Figure 18.2 shows an example of a chart where the development of the so-called housekeeping index is displayed. The observation items in this application of behavioural sampling were observable conditions at the workplaces related to housekeeping, i.e. items that represent results of behaviour rather than the actual behaviour itself. 

Behavioural sampling in its original version has been criticised because it represents a view of workers as objects for control rather than as active participants in the work processes to improve safety. It is thus not well suited for application where a more participatory tradition in SHE practice prevails. In Finland, a version of behavioural sampling called Tuttava has been developed to make it more suited for these conditions. Tuttava addresses such problems as (Saari, 1998) ... 

Behavioural sampling being based on Van Court Hare s principles of first-order feedback. No lasting effects other than those concerned with workers behaviour and cognition are expected. In Tuttava, so-called implementation teams of workers and supervisors analyse the causes of deviations in order to come up with technical, organisational and procedural measures to prevent recurrence and to facilitate correct behaviour. These teams represent the equivalent of the so-called quality improvement projects. 

Exercise Evaluate both the original behavioural sampling technique and Tuttava in relation to the criteria in Chapter 11. Discuss how behavioural sampling may affect the behaviour of the employees and the supervisors. 

Behavioural sampling is a rather elaborate method. Below is an example of a simplified method that has been developed in indnstry. 

This section will look at formation and fluid data gathering before significant amounts of fluid have been produced hence describing how the static reservoir is sampled. Data gathered prior to production provides vital information, used to predict reservoir behaviour under dynamic conditions. Without this baseline data no meaningful reservoir simulation can be carried out. The other major benefit of data gathered at initial reservoir conditions is that pressure and fluid distribution are in equilibrium this is usuaily not the case once production commences. Data gathered at initial conditions is therefore not complicated... 

The technological importance of thin films in snch areas as semicondnctor devices and sensors has led to a demand for mechanical property infonnation for these systems. Measuring the elastic modnlns for thin films is mnch harder than the corresponding measurement for bnlk samples, since the results obtained by traditional indentation methods are strongly perturbed by the properties of the substrate material. Additionally, the behaviour of the film under conditions of low load, which is necessary for the measnrement of thin-film properties, is strongly inflnenced by surface forces [75]. Since the force microscope is both sensitive to surface forces and has extremely high depth resolntion, it shows considerable promise as a teclnhqne for the mechanical characterization of thin films. 

This corresponds to the physician s stethoscope case mentioned above, and has been realized [208] by bringing one leg of a resonatmg 33 kHz quartz tiinmg fork close to the surface of a sample, which is being rastered in the x-y plane. As the fork-leg nears the sample, the fork s resonant frequency and therefore its amplitude is changed by interaction with the surface. Since the behaviour of the system appears to be dependent on the gas pressure, it may be assumed that the coupling is due to hydrodynamic mteractions within the fork-air-sample gap. Since the fork tip-sample distance is approximately 200 pm -1.120), tire teclmique is sensitive to the near-field component of the scattered acoustic signal. 1 pm lateral and 10 mn vertical resolutions have been obtained by the SNAM. 

Under compression or shear most polymers show qualitatively similar behaviour. However, under the application of tensile stress, two different defonnation processes after the yield point are known. Ductile polymers elongate in an irreversible process similar to flow, while brittle systems whiten due the fonnation of microvoids. These voids rapidly grow and lead to sample failure [50, 51]- The reason for these conspicuously different defonnation mechanisms are thought to be related to the local dynamics of the polymer chains and to the entanglement network density. 

Figure C2.5.2. Scaling of the number of MBS C(MES) (squares) is shown for the hydrophobic parameter = -0.1 and A = 0.6. Data were obtained for the cubic lattice. The pairs of squares for each represent the quenched averages for different samples of 30 sequences. The number of compact stmctures C(CS) and self-avoiding confonnations C(SAW) are also displayed to underscore the dramatic difference of scaling behaviour of C(MES) and C(CS) (or C(SAW)). It is clear that C(MES) remains practically flat, i.e. it grows no faster than In N.

Abstract. A model of the conformational transitions of the nucleic acid molecule during the water adsorption-desorption cycle is proposed. The nucleic acid-water system is considered as an open system. The model describes the transitions between three main conformations of wet nucleic acid samples A-, B- and unordered forms. The analysis of kinetic equations shows the non-trivial bifurcation behaviour of the system which leads to the multistability. This fact allows one to explain the hysteresis phenomena observed experimentally in the nucleic acid-water system. The problem of self-organization in the nucleic acid-water system is of great importance for revealing physical mechanisms of the functioning of nucleic acids and for many specific practical fields. 

The number and kind of defects in a given specimen, as well as the crystal habit and with it the proportion of different crystal faces exposed, will in general depend in considerable degree on the details of preparation. The production of a standard sample of a given chemical substance, having reproducible adsorptive behaviour, remains therefore as much an art as a science. 

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