How thick should Martian dust be to protect from radiation?

[toymaker]

How thick should be the layer of Martian dust so that potential bacteria or primitive liforms would be protect from radiation ?<br />I would be very grateful for an answer.

 

[vogon13]

IIRC (pretty iffy on this), think I saw the figure of 1 meter of Martian surface materials being a good start.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>