Pipelines are considered the safest means of transporting mass goods. In particular, they are used to transport liquids and gases. When talking about pipeline safety, it is important to distinguish between supply safety for consumers who depend on pipelines, on the one hand, and safety (in the sense of personal safety, environmental and property protection) against potential hazards to personnel and the environment that may be caused by these pipelines, on the other.
| Supply Safety | Safety for Potential Dangers | ||
| Target: | High reliability (few shortfalls and low standstill times) | Target: | Personal safety, environmental or water protection, and protection of real assets |
The security of supply of gas pipelines for supplying energy to the public is very important, as many industrial activities and households rely heavily on gas as an energy medium. This high dependence is attributed to the fact that no allowance is made for the storage of gas at the consumer's premises, so a shortage in a gas pipeline can lead to short-term problems with energy supply to consumers.
In the case of pipelines transporting crude oil and petroleum products, the situation is similar, even if not directly noticeable to individual consumers. Therefore, the safe and continuous supply of crude products to refineries connected by a crude oil pipeline is vital, since supplies are only sufficient for a few days. If the supply fails after this short period, it would result in an interruption in the operation of the refineries involved and combined with this circumstance would result in high costs and possibly supply problems for consumers of the refined products.
Therefore, supply safety essentially reflects the issue of availability with the goal of operating pipeline facilities with the shortest possible downtimes and shortages. In contrast, it is vital for personnel safety and environmental protection to eliminate or reduce the hazards associated with pipeline operation as much as possible or to an acceptable level.
In the case of pipelines transporting hazardous liquids, the potential danger to persons (employer and third parties) is mainly caused by the fire and explosion risks and the toxicity of the liquids transported. Additional danger arises for any pressurized container, for example, from mechanical shocks that can cause damage, such as a pipe burst. Compared to high-pressure gas pipelines, this hazard is lower for liquid pipelines because of the lower compressibility of the transport fluids. This result is underlined by the fact that liquid pipelines cannot exhibit large crack lengths due to the high speed of pressure waves, which is possible in gas pipelines.
The protection of water is of great importance for the safety of pipelines transporting crude oil and oil products, which is underscored by particularly strict legislation in this area. The technical safety requirements arising from this aspect are therefore understandable if one imagines the potential threat and the possible consequences of damage. Finally, the protection of the environment should be clearly mentioned as a safety goal, taking into account the protection of transportation routes, since they are often crossed by other pipelines due to their long dimensions or because they run parallel to other pipelines. Against the background of the specified safety objectives, considerations regarding their achievement are reflected by defining technical requirements for pipelines regarding their condition, method of operation and maintenance. This will minimize the risk of damage (primary safety objective). On the other hand, damage (which cannot be completely eliminated) should be detected using appropriate methodologies and thus positioned so that the consequences are minimized by the applied measures and damage is prevented (secondary safety objective). This would minimize the extent of damage.
| Primary | Secondary |
| Demage prevention | Limitation of the damage impacts |
Since pipelines have a high throughput (several thousand m3 per hour in the case of large pipelines), the need for rapid leak or damage detection and positioning and effective damage prevention in the event of a pipeline rupture becomes particularly evident because of the potential magnitude of damage, despite the very low probability of damage. The main factors by which pipeline safety is determined are the following..
Most relevant to primary pipeline safety is the technical condition of the entire plant system, which results from the design, planning, construction and selection of equipment. The operating procedure, which is time-dependent and has a significant impact on pipeline safety, must be defined in such a way that load assumptions (e.g., allowable operating pressure) are not exceeded, even in the event of failures. Despite the highly developed automation in pipeline operation, operating personnel have a great responsibility and an important function, especially in the case of large and branched pipelines. Maintenance, which includes monitoring, repair and inspection measures, must maintain the nominal condition of the pipeline installation, including its safety components. These provisions should be based, first, on the equipment required for safe operation of the pipeline and, second, on the pipeline body itself that is under pressure. In addition to the operating parameters such as internal pressure and internal corrosion (if applicable) that must be taken into account, it is also important to consider external influences on the pipeline (which is usually laid underground), such as external corrosion or additional stresses due to ground movements in mining-impacted areas. Finally, third-party interferences are important because they can adversely affect pipeline safety.