Casing shear ram.
Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global Standards
Source: Oil & Gas UK, Guidelines on subsea BOP systems, Issue 1, July 2012, Global Standards
Offshore Installations (Construction and Survey) Regulations 1974.
Source: Prevention of Fire and Explosion, and Emergency Response on Offshore Installations, Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995, Approved Code of Practice and guidance (UK HSE L65), Second Edition, 1997. Regulatory Guidance