What is HAZID
A Hazard is a characteristic of a system, plant or process with the potential for harm. Hazards are generally labelled as one of five types:
- Materials hazards involving substances with a potential for harm or damage. Examples of material hazards are those associated with flammable materials with a potential for fire or explosion that may cause harm to life, health, property or the environment;
- Physical hazards involving conditions or situations with a potential for physical harm. Physical hazards include stored energy, electricity, ergonomic hazards, radiation, heat and cold stress, vibration, and noise;
- Biological hazards involving biological agents with a potential for harm. Examples of biological hazards are viruses, parasites, bacteria, food, fungi and foreign toxins;
- Psychological hazards, and
- Ergonomic hazards
Tweeddale (2003) proposes that such hazards are generally derived from the energy of the systems in operation and that the types of energy include:
- Kinetic energy, e.g. momentum of moving vehicles;
- Potential energy, e.g. the energy stored in heavy weight that may fill;
- Chemical hazards, e.g. the energy obtained from combustion of material as asbestos on people and the environment and may arise from toxic gas release or spills.
A hazardous situation that has come to pass is called an incident. An incident may have an impact on the health and safety of people, the natural (biophysical) environment, property, production, inability to honour contracts to provide service) and business reputation Hazard and possibility (probability/likelihood) interact together to create RISK.
Identifying HAZARD
The quality of hazard analysis depends on the ability of the analyst to understand the plant and processes at the facility and assess what might go wrong. The first step in a hazard analysis is therefore to identify the hazardous scenarios and, as such, hazard identification is a very critical step in the hazard analysis process. Hazard identification involves the systematic identification of possible hazards, both on-site, and off-site, associated with a facility and its operation. When identifying hazards, the analyst must take into account the operational and organisational failures as well as the safeguards designed to prevent or mitigate the effects of hazardous incidents. There is a large number of techniques available for hazards identification and the number is still growing; the different techniques have their own field of applications. Common Methods:
Each system was subjected to a review using a brainstorming approach prompted by the guidewords found in table below::
| Guideword Group | Guideword |
| Natural and Environmental | 1. Climate Extremes 2. Lightnings 3. Earthquakes 4. Erosion 5. Subsidence |
| Created (Man-Made) Hazards | 1. Security Hazards 2. Terrorists Activity |
| Infrastructure | 1. Normal Communications 2. Communications for Contingency Planning 3. Supply Support |
| Effect of the Facility on the Surroundings | 1. Geographical – Infrastructure 2. Proximity to Population 3. Adjacent Land Use 4. Proximity to Transport Corridors 5. Environmental Issues 6. Social Issues |
| Environmental Damage | 1. Continuous Plan Discharges to Air 2. Continuous Plant Discharges to Water 3. Continuous Plant Discharges to Soil 4. Emergency/Upset Discharges 5. Contaminated Ground 6. Facility Impact 7. Water Disposal Options 8. Timing of Construction |
| Control Methods/Philosophy | 1. Manning/Operations Philosophy 2. Operations Concept 3. Maintenance Philosophy 4. Control Philosophy 5. Manning Level 6. Emergency Response 7. Concurrent Operations 8. Start-up Shutdown |
| Fire and Explosion Hazards | 1. Stored Flammables 2. Sources of Ignition 3. Equipment Layout 4. Fire Protection and Response 5. Operator Protection |
| Process Hazards | 1. Inventory 2. Release of Inventory 3. Over Pressure 4. Over/Under Temperature 5. Excess/Zero Level 6. Wrong Composition/Phase |
| Utility Systems | 1. Firewater Systems 2. Fuel Gas 3. Heating Medium 4. Diesel Fuel 5. Power Supply 6. Steam 7. Drains 8. Inert Gas 9. Waste Storage and Treatment 10. Chemical/Fuel Storage 11. Potable Water 12. Sewerage |
| Maintenance Hazards | 1. Access Requirements 2. Override Necessity 3. Bypasses Required 4. Commonality of Equipment 5. Heavy Lifting Requirements 6. Transport |
| Construction/Existing Facilities | 1. Tie-ins (shutdown requirements) 2. Concurrent Operations 3. Reuse of Material 4. Common Equipment Capacity Interface – Shutdown/Blowdown/ESD 5. Skid Dimensions (weight handling/equipment congestion) 6. Soil Contamination (existing facilities) 7. Mobilisation/ Demobilisation |
| Health Hazards | 1. Disease Hazards 2. Physical |
The process followed for this method was to assess each system or node using the following sequence.
2. Consider whether there is a hazard associated with each guideword and discuss its applicability in relation to the system / section under review.
3. For each applicable hazard, consider if the hazard can be removed or reduced. If a hazard cannot be removed, note the main existing or planned safeguards and discuss their adequacy.
4. Agree risk rating, if applicable.
5. Identify Barriers, as applicable.
6. Make recommendations for further action, as required. Where there is no recommendation the team considered that the safeguards were adequate and the risk ALARP.
Then, a typical Risk Assessment Matrix (RAM) to use to rank the risks.
Designers are generally try to stay in Green or Yellow area. In case the risk sits in Orange or Red, recommendation will be taken to ALARP the risk.
Here is a typical HAZID Worksheet
