On May 4, 2026, the Mexican Official Standard NOM-021-ASEA-2026, Marine Seismic Surveys for Surface Reconnaissance and Exploration (the “NOM”), issued by the Agencia de Seguridad, Energía y Ambiente (ASEA), was published in the Diario Oficial de la Federación (Official Journal of the Federation).
Object
The purpose of the NOM is to establish the technical specifications and safety measures, as well as environmental protection measures, applicable to Surface Reconnaissance and Exploration activities by means of Marine Seismic Surveys.
Scope of application
The NOM is applicable to regulated parties, in terms of ASEA regulations, that carry out Surface Reconnaissance and Exploration activities through Marine Seismic Prospecting in marine areas under national jurisdiction.
Main obligations
NOM establishes, among others, the following obligations:
- Implementation of environmental monitoring systems, including:
- Marine Mammal Observers (PSO).
- Passive Acoustic Monitoring (PAM).
- Monitoring prior to the start of activities, to be carried out:
- For at least 30 minutes, or
- 60 minutes in low visibility conditions or when using PAM.
- Establishment of exclusion and monitoring zones, within which:
- Seismic shots may not be fired in the presence of protected species.
- Activities should be suspended in case of detection of fauna within these zones.
- Application of the soft-start method, prior to the start of activities, subject to specific monitoring conditions.
- Suspension of operations when:
- Marine mammals or other species are detected in the exclusion zone.
- There are failures in the monitoring systems, in which case a limited time is foreseen for their reestablishment.
- Registration and documentation of activities, including:
- Foliated logs.
- Sighting reports.
- Record of operational events and actions taken.
- Technical requirements for equipment and personnel, including criteria applicable to:
- The PSO.
- PAM system operators.
- Seismic acquisition equipment.
Entry into force
The NOM will become effective 180 calendar days after its publication in the Official Gazette of the Federation.
At Vega Guerrero & Asociados we have a team specialized in environmental and regulatory matters. Should you require advice on the implementation of this NOM or its impact on your operations, please do not hesitate to contact us.
