Safety Information for the Residents
Natural gas transmission system
INFORMATIVE MATERIAL FOR THE PUBLIC
on actions in the event of an industrial accident and the intended protective measures
The purpose of this material is to inform the residents and companies located in the vicinity of JSC “Conexus Baltic Grid” (hereinafter “Conexus”) natural gas transmission system’s objects about potential hazards and necessary actions in the event of an accident at natural gas transmission system’s objects, as well as the intended protective measures.
The information material was developed in December 2023 in accordance with the requirements of Paragraph 41 of the Cabinet Regulation of the Republic of Latvia adopted December 5, 2006 “Methodology for Determining the Protection Zones of Energy Infrastructure Objects”.
Contact information
“Conexus Baltic Grid” AS
Telephone: 67087900
E-mail [email protected]
Possibilities to obtain additional information
More information about Conexus is available on the website https://www.conexus.lv/.
Additional information can be obtained by sending a letter by post to the legal address of JSC “Conexus Baltic Grid” (Riga, 14 Stigu Street, LV-1021) or by email ([email protected]).
Description of activities
Conexus is the only natural gas transmission system operator in Latvia and enables certified traders to use the Latvian natural gas transmission system for trading not only in Latvia but also in the neighbouring regions.
Conexus’ gas transmission system consists of more than 1190 km of transmission pipelines with branches and technological objects. The technological objects of the gas transmission system are located throughout Latvia.
The infrastructure of the Latvian natural gas transmission system consists of:
- gas pipelines with shut-off valves;
- gas regulating stations, gas regulating units and gas metering stations;
- telemetry, communication and power supply systems;
- electrochemical protection system;
- security systems.
Information on hazardous substances
Natural gas, CAS No. 8006-14-2, EC No. 232-343-9
Characteristic hazards:
- H220: Extremely flammable gas (Category 1)
- H280: Contains gas under pressure; may explode if heated
Effects caused by exposure to the substance: Mixture of chemical substances lighter than air. The main component is methane (~ 98%) and other gases and compounds. Natural gas can form an explosive mixture with air. Natural gas in the gas transmission system is odourless, and in order for natural gas to be detectable by humans, the transmission system operator adds ethyl mercaptan to odourise it. As a result, natural gas acquires a specific odour before it is supplied to consumers.
Symptoms and effects: at low concentrations, natural gas can produce a narcotic effect. Symptoms may include dizziness, headache, nausea, and loss of coordination. At high concentrations in enclosed spaces, the amount of oxygen inhalable will decrease and suffocating effects of natural gas are possible. Symptoms: movement impairment, unconsciousness, vomiting. The exposed person may be unable to feel warning symptoms of possible asphyxiation. Usually, the person falls into a deep sleep (unconsciousness) ending in death.
Information on industrial accident hazards and risk factors
Given the properties of the gas and the conditions of its transmission, a gas leak may be associated with the gas:
- spreading in the atmosphere without ignition;
- ignition followed by a jet fire;
- delayed ignition, which can develop into a gas cloud fire or explosion.
Natural gas is lighter than air, so in the event of a leakage, it will spread to the upper layers of the atmosphere without forming a gas cloud at ground level. Leaked gas can also accumulate in confined spaces, such as rooms.
Immediate ignition sources at the moment of leakage may be thermal effects resulting from metal disintegration or sparks generated by the friction of abrasive materials resulting from the gas leak under pressure.
Delayed ignition can result in a fire in the escaped gas cloud or an explosion of the explosive mixture of gas and air (the upper explosive limit of the gas is 15%, and the lower limit is 5%), which may also be followed by a jet fire.
The ignition of an explosive mixture of gas and air can be caused by external ignition sources, such as the use of any open flame etc., sparking or fire-causing activities in the area where the explosive cloud is spreading.
In the event of a natural gas leakage without ignition, the escape of natural gas at high pressure will cause a very loud noise (similar to a jet aircraft), which will be audible at a great distance and may also cause irreversible damage to the gas pipeline, objects and the surrounding environment. It also creates explosive and fire-hazardous concentration zone, where any small source of energy (e.g., a spark) can cause an explosion.
In the event of a natural gas leak with ignition, heat radiation, combustion by-products and smoke are expected to spread in the vicinity of the fire.
In the event of a natural gas cloud explosion, a pressure wave spreads that can destroy buildings and endanger human life and the surrounding environment. The blast radius and consequences of an explosion depend on the amount of natural gas involved in the explosion.
People may suffer from the impact of flying objects caused by the blast wave, which may result in death or serious bodily injury. The natural gas transmission system gas pipeline will be irreparably damaged.
Upon discovering such an accident, Conexus will immediately shut off the damaged section of the gas pipeline, the remaining natural gas will escape from the pipeline or burn out, and the emergency response work will begin immediately.
Warning! In the event of damage to the gas pipeline followed by gas combustion, a life-threatening thermal radiation zone (maximum 1% lethal distance) of up to 200 m may form around the natural gas leakage site. You must leave this zone immediately!
What to do in an emergency
If you hear an explosion or a loud noise characteristic to a high-pressure natural gas leak and/or smell the specific odour of natural gas, which indicates a high concentration of natural gas, you must immediately stop all work and other activities that could cause sparks or flames and report the natural gas leak to the State Fire and Rescue Service by calling 112, stating your location (address), the possible location of the natural gas leak, your name, surname and telephone number. If possible, make sure that those around you are aware of the accident and know what to do.
Warning neighbouring businesses and residents about the danger
Conexus has established procedures for cooperation with the State Fire and Rescue Service and other emergency (rescue) services, and for response and recovery operations in the event of an accident. In the event of an industrial accident, all necessary state institutions, local governments, and Conexus personnel are notified.
What to do if you receive an emergency alert
Listen to the announcements made by the State Fire and Rescue Service, the State Police or Conexus personnel and follow them.
Do not use open flames or perform any actions that could cause sparks or flames. If possible, make sure that those around you are aware of the industrial accident and know what to do.
Action when indoors: on receiving an accident alert, close and seal windows, doors, ventilation hatches, air vents, flues, and turn off air conditioning.
Action when outdoors: on receiving an accident alert, immediately move away from the dangerous area in a direction perpendicular to the wind (so that the wind is blowing from the side). If this is not possible, seek shelter in the nearest building.
Evacuation: the public will be informed of the need to evacuate and the evacuation procedures through the media or via the loudspeakers of emergency services or police. In case of evacuation, if possible, take your personal identification documents, money, valuables, food supplies and only the necessary clothing. Before evacuating, turn off the electricity, gas and water supplies. Notify neighbours of the need to evacuate and help children, disabled and elderly people to prepare for evacuation.
In case of health concerns (headache, weakness, balance problems and vomiting), got to the nearest medical facility or, if there are any casualties near you, immediately call the Emergency Medical Service by dialling 113.