1.1.1.2.

The technique is used to determine a number of factors such as:

• Determination of compliance with design rules e.g. correctly supported and mounted pipework, or cabling to reduce stress during operation.
• Identification of potential cascade failures due to system interaction.
• Identification of potential areas for system maintenance errors.
• Identification of potential areas for system malfunction due to the environment.

1.1.1.4.

Zonal Hazard Analysis is also used to determine whether a fault at a particular location can affect the independence of the equipment; for example a hydraulic failure could affect a supposedly independent electrical system in the same vicinity or, alternatively, a steam leak could cause the area, in which isolation of the leak can be effected, to be inaccessible to the operator. The identification of this particular Hazard would lead to the recommendation to provide a remote isolation facility that is protected from the effects of the steam leak.

1.1.2.1.

Zonal Hazard Analysis should start as soon as physical layout is being considered within the design process. The analysis should be based on the latest issue of drawings, physical mockups or synthetic simulations, together with examination of the first representative system installation. The usefulness of a 3D-CAD tool from the very early conceptual phase should not be overlooked.

1.1.3.1.

Advantages

• The technique considers the installation of the equipment and examines the potential safety problems associated with that installation.
• The use of Zonal Hazard Analysis provides the potential to discover how various parts of a system might influence, or might be influenced by their surroundings. These surroundings could be either physical (equipment / human etc.) or environmental (temperature / humidity / wild life (bird strike or pollution) / sea etc.).
• Maintenance and Procedural errors can be reviewed to establish any potential areas for concern, which could be missed if individual systems were only considered in isolation. The need to enter a hazardous area, for example to isolate the system electrically may be discovered when Zonal Hazard Analysis is conducted.

1.1.5.2.

Zonal Hazard Analysis is particularly useful in identifying possible common cause Hazards i.e. where failure of a component, or part of a system, may cause associated hazards in the immediate area.

1.1.5.4.

Checklists can be utilized in the process to identify Hazards. They can also be used to check that designs comply with certain standards and codes of practice, or that protective measures are correctly employed. They are however, reliant on the knowledge and experience of those persons compiling the lists and, whilst they could provide significant safety benefits for systems and equipment, they depend heavily upon the ability of the analyst(s).

1.1.5.6.

During a safety programme there may be individual System Hazard Analyses covering the discrete Hazard Analyses for the particular parts of a system. Where a number of systems are fitted to a platform, the integration of these systems should also be subject to a Zonal Hazard Analysis. A system may achieve a relatively low risk classification when considered in isolation, but when installed on a platform or next to another system there may be potential external influences, which could introduce new Hazards or increase Risks.