Could you please let me know the address for where the the health and safety test is conducted in London?

The central London test center is in Southwark
. 
To book either call 0844 682 0844 or visit this website online at
http://www.cslinks.co.uk

This will certainly fetch you all the information that you need to have for the booking for the right CSCS test that is suited for your job profile.