EP - Natural Gas Emergencies & Fires
PURPOSE - Guide for gas system infrastructure, operational awareness, and risk assessment in gas emergencies.
BACKGROUND - NYC increasingly depends on natural gas for energy, which poses risks due to aging infrastructure and rising incidents of gas leaks. As a result, it is essential to have robust measures in place to ensure safety and efficient response to any gas-related incidents.
PROPERTIES OF NATURAL GAS - Mainly methane; flammable, colorless, odorless (mercaptan added for detection) aiding in safety. - Explosive range: 5% - 15% concentration makes precise monitoring crucial. - Lighter than air, non-toxic but can displace oxygen in confined spaces, leading to asphyxiation risks.
GAS SYSTEM INFRASTRUCTURE - Con Edison and National Grid distribute gas in different NYC regions, each having specific operational protocols. - Gate stations significantly increase gas volume and pressure rapidly; unconfined gas burns without explosion, which is vital for safety protocols. - Main components include:
Transmission mains: High-pressure pipelines transporting gas from production areas.
Distribution mains: Lower-pressure lines delivering gas to consumers.
Regulator stations: Control pressure levels and ensure safe delivery of gas.
STRATEGY & TACTICS - Most emergencies resolved through simple mitigation strategies that include immediate assessments and quick actions. - Major Gas Emergencies are identified by significant infrastructure damage, high gas readings, or gas migration requiring prompt attention.
RESPONSE PROCEDURES - Investigation should commence using calibrated gas detectors; timely evacuations may be necessary based on readings. - Stay clear of potential explosive areas to avoid catastrophic outcomes; positioning apparatus away from risk zones is key. - Use appropriate protective equipment and continuously monitor gas levels to ensure safety during response operations.
MAJOR GAS EMERGENCIES - Defined by serious risks that require special resources such as specialized teams and advanced equipment. - Utilize specific indicators, including gas concentrations of 10% LEL or higher to identify level of risk and determine necessary actions.
MITIGATION - Effective strategies include ventilating areas to disperse gas, eliminating ignition sources, and controlling leaks by closing relevant valves. - Transfer operation responsibilities to the Utility Company once conditions are deemed secure to ensure safety and efficiency.
INCIDENT COMMAND - Incident Commander evaluates conditions continuously, establishes command posts for coordination, and ensures monitoring of gas levels throughout the emergency. - Continuous updates on the situation and resource coordination are essential to mitigate risks effectively.
CHECKLIST & RESOURCES - Ensure incident reports are updated in real-time, manage evacuations efficiently, and maintain communication with Utility Companies for support regarding infrastructure assessments and safety measures.