Sea Marshall 121.5 MHz Maritime Survivor Locating Systems

Man overboard locate and rescue systems

Sea Marshall Maritime Survivor Locating Systems (MSLS) have been saving lives in the maritime industry for over 30 years.  First launched in 1979, they are now the leading man overboard system in the North Sea, where over 5,000 units are in use daily. Industry professionals worldwide use the Sea Marshall system, including:

 

  • Offshore windfarms, service providers and maintenance crews
  • Offshore oil and gas producers, service vessels and helicopter transit operators
  • Offshore exploration and construction companies
  • Coast guard and rescue authorities
  • Port and harbour authorities
  • Commercial fishing fleets, fishfarms and aquaculture 

 

Suitable for large or small crew numbers, Sea Marshall MSLS are an independent, self-managed man overboard alert and rescue system that safeguards crew from undetected falls overboard. Offering 24/7 crew safety monitoring and signal tracking, the system comprises one or more alerting units - worn by crew - and a dedicated receiver (base unit) on board the vessel. Mobilarm recommends you fit your Sea Marshall alerting unit to lifejackets to maximise your chances of survival in a man overboard event.

Sea Marshall Alerting Units Mobilarm Base Units Intelligent Lifejackets

When activated - automatically when submerged in water or manually - the alerting unit transmits a continuous homing signal on 121.5 MHz. The base unit onboard the parent vessel continuously monitors the 121.5 MHz frequency and raises the alarm when it detects the emergency signal. The base unit indicates the direction and approximate range to the man overboard, enabling crew to carry out the rescue.

If outside help is need, the homing signal can be tracked by international Search and Rescue, who carry direction finding equipment on board rescue assets. Note however that the COSPAS-SARSAT satellite system ceased monitoring 121.5 MHz on 1 February 2009 - SAR will not be notified automatically to a man overboard event involving a Sea Marshall device.