The current scenario for identifying design derived risks within a project is to develop a risk register or some alternative method of manually collating risks.
Although this method may work in a satisfactory way for most projects, it’s not particularly robust and is not truly objective. The developed risk register will probably calculate the risk based on the assessed hazard and likelihood of occurrence. But, these factors are often assessed in a subjective way. Indeed, the initial assessment of significant risks (or the initial assessment of hazards) will be the responsibility of the individual designers, with the hazard level being selected based on experience and prior knowledge.
Hazard – A potential source of harm
Risk – The combination of the probability of harm occurring and the severity of the harm
But, this is hardly a satisfactory way of managing something as important as health and safety. Most designers will not have a detailed understanding of the processes involved in construction delivery and facilities management.
This is where BIM could provide significant benefits in the identification and elimination (or reduction) of significant hazards and risks.
PAS – Publicly Available Specification (the precursor to a British Standard)
The second draft of PAS1192-6, Specification for collaborative sharing and use of structured hazard and risk information for Health and Safety, was published in early 2017 for comments. With the formal final release planned for later 2017. The document primarily focuses on using BIM for the collation and management of hazards and risks. The collation of risks within a model will enable wider stakeholder access to the items and improved collaboration.
Significant Risk – An above moderate risk after mitigation measures
PAS 1192-6 (draft version) proposes the use of three methods for collating and developing Health and Safety information a tabulated register; COBie, through the COBie.Issue sheet and IFC through the project model. The identification and collation of risks and then the tracking of the risks through the COBie.Issue spreadsheet would represent a major step forward. But beyond COBie, the direct use of a model with IFC parameters would represent a significant improvement over current methods of collating H&S data.
PAS 1192-6 Annex A also goes a step further by including improvements to the IFC risk property set (Pset_Risk) as the HSE_Risk_UK (an expanded and improved risk property set).
However, what is often misunderstood is that COBie is a subset of IFC data, it’s just a small proportion of the data expressed as a multi-sheet spreadsheet.
So for BIM health and safety to work as a fully joined up design approach the risks should be managed directly within the design models.
COBie can be used as an effective way of viewing the risks. But, the COBie format (as it currently exists) is rigid. It does allow, in some circumstances, for additional data columns. But, the inclusion of additional data columns is difficult to implement and is not widely supported by model authoring tools.
PAS 1192-6 Annex A contains information on the mapping between COBie and the IFC risk property set.
A better long-term and flexible solution would be to look at managing health and safety directly within a design model from the start.
IFC has a developed and a joined-up framework for managing hazards and risks. COBie.Issue data fields map directly to IFC health and safety associated parameters, enabling the production of a COBie.Issue export from the IFC data. This provides additional support that IFC should be the primary place for developing the data, the model data comes first, the COBie export is produced from the IFC data.
IFC has a whole set of predefined property sets. Property sets provide a list of data fields for given objects. A door, which has a property set (Pset_DoorCommon in IFC terminology) contains predefined parameters such as:
IFC has a predefined risk property set Pset_Risk
The defined parameters from Pset_Risk include:
This provides interesting possibilities. Being able to collate all significant risks and hazards within a model would vastly improve on our current methods.
But, it gets even better. An IFC model is similar to a nested database (it’s actually just a very large text file, although many applications convert the text file to a database structure for easier management). This results in every IFC property set being linked to something else within the model. The Pset.DoorCommon (mentioned earlier) will be linked to doors within the model (IfcDoor).
But, the IFC risk property sets do not have to be linked to physical objects, instead, they can be associated with processes (or activities). You may wonder why the risk property is not linked directly to an IFC object. When considered a little deeper the linking of the risk property set to a process provides increased opportunities.
In most circumstances, a risk will not occur unless someone or something is doing something. The ‘something’ is the process or the activity.
For a risk to be realised a process takes place
As an example, consider a light fitting. The light fitting correctly installed within a ceiling will not present a risk. Even if the light fitting was located in a large open space 8m above floor level, the light fitting itself would not present a risk. But, if you add in a process, such as the replacement of a lamp or the removal of the fitting, we now get a risk. So a process, such as the maintenance activity to replace a lamp, will introduce a fall from height hazard (a potential source of harm), a high likelihood of occurring and a subsequently high-risk rating (without an appropriately safe and suitable means of access).
The IFC risk property set also allows for mitigating actions (or preventative measures) to be recorded against the risk. With preventative measures identified the risk can be re-assessed (and hopefully eliminated or reduced to an acceptable level).
This means that the IFC framework associates a risk to a process and a process is associated with an object (such as a light fitting).
The risk property set (Pset_Risk) can also be associated with any IfcObject. This also allows the risk item to be associated with other IFC entities such as IfcTask andIfcSpace.
This opens up multiple possibilities for the use of the risk property set.
The IFC joined-up approach to risk isn’t new. But, it doesn’t appear to have been widely implemented (please let me know if you are aware of any projects that have taken the IFC approach to risk management). So, it’s new in the context of not being widely used.
Costain used the IFC risk property set (Pset_Risk) on the A556 Knutsford to Bowdon improvement scheme.
Model risk management presents significant improvements over the current (and largely subjective) risk registers.
BIM can save lives
BIM can play a major part in reducing construction and maintenance related accidents and injuries by managing and reducing risks in a truly objective way. The integration and management of risks within a model will just be the start.
Ian Yeo firstname.lastname@example.org