The following changes will be made to Guide 115 in the 2024 edition of the ERG:
In the section “POTENTIAL HAZARDS – FIRE OR EXPLOSION”:
Guide 115 currently does not address the rapid phase transition (RPT) phenomena that LNG may experience when in contact with water.
- proposed addition: “When an LNG release is on or near water, exercise caution as rapid phase transitions may occur from the liquid to vapor phase with an associated rapid pressure increase.”
- accepted addition: “CAUTION: When LNG – Liquefied natural gas (UN1972) is released on or near water, product may vaporize explosively.”
- the ERG partner organizations agreed to this accepted addition to have a concise statement for ease of readability during an incident. Rather than mentioning the RPT phenomenon directly, the potential hazard is highlighted
In the section “POTENTIAL HAZARDS – HEALTH”:
Inhalation issues are more applicable in closed or confined areas versus in open air.
- original statement: “Vapors may cause dizziness or asphyxiation without warning.”
- proposed and accepted modification: “Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas.”
- this amendment will also be made in other ERG guides containing the same original text, including Guides 116, 120, 122, 126, 127, 128, 129, 130, 131, 132, 160, and 174
Incorporate “cryogenic liquid”, which is not currently mentioned in the Guide 115 statement regarding contact hazards.
- original statement: “Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite.”
- Proposed and accepted modification: “Contact with gas, liquefied gas, or cryogenic liquid may cause burns, severe injury, and/or frostbite.”
- this amendment will also be made in other ERG guides to which other cryogenic liquids are assigned, including Guides 120, 122, and 168
In the section “EMERGENCY RESPONSE – FIRE”:
Under “Fire Involving Tanks”, the researchers suggested that the second and third bullet points should be combined into one bullet point, so that the user reads them together for context, as pressure relief devices could be affected by icing. This is not a technical issue, but rather a human factors issue.
- original statements:
- “Cool containers with flooding quantities of water until well after fire is out.”
- “Do not direct water at source of leak or safety devices; icing may occur.”
- proposed modification: “Avoiding the container’s pressure relief device and the source of the leak, cool the container with flooding quantities of water until well after the fire is out. Activation of the pressure relief device may be delayed, and icing may occur.”
- decision by the ERG partner organizations: Keep the original statements as they are. The suggested modification is too long and reduces clarity. However, any feedback from stakeholders would be welcome for consideration for future editions of the ERG
Researchers also suggested combining two (2) bullet points in the section, “EMERGENCY RESPONSE – FIRE”, so that users would read the guidance on cooling containers in a fire with water and the warning about icing of pressure relief devices, at the same time. However, it was decided not to include this change in the next edition of the ERG, as it was felt the text would be too long and not easy to read. We welcome feedback on this from stakeholders for future editions of the ERG.
Once these changes are made, there is no need to develop a separate guide for LNG at this time. We will continue to review the ERG regularly to make sure that it contains the most up-to-date information.
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