The <a href="https://en.wikipedia.org/wiki/Byford_Dolphin" id="mw6A" rel="mw:WikiLink" title="Byford Dolphin">Byford Dolphin</a> <a href="https://en.wikipedia.org/wiki/Diving_bell" id="mw6Q" rel="mw:WikiLink" title="Diving bell">diving bell</a> accident kills five and leaves one severely injured.