The main results of this thesis are:

• A survey of available radiation shielding materials has also been presented.

• An optimal, passive, multilayer radiation shield, attenuating neutrons and photons, has been designed and simulated and outperforms many other currently used radiation shielding designs used in underground laboratories and particle physics experiments.

• A proposed complete shielding design for COBRA featuring, an active element close to the CZT detectors, was simulated and costed indicating that an active veto improves a simple passive shield alone.

• The simulations of internal radioactive contaminants within the constituents of the active veto could be used to estimate limits on the intrinsic radioactive sources in the active veto components, thus making it possible to gauge whether the design offers a feasible solution.

• A new, simple readout and data analysis method for single channel, room-temperature semiconductor detectors was introduced (using Frisch collar detectors) that significantly improves energy resolution.

• To further simplify and improve energy resolution, it was demonstrated that a room-temperature Heusser-type detector made from CZT semiconductors, immersed in a safe liquid scintillator cocktail is a viable concept.

• The question of how many counts make a peak when searching for a Gaussian peak on a flat background has been addressed. A Gaussian peak containing as low as 14 counts total can be identified at 3σ with 95% efficiency. A 5σ detection roughly doubles the amount of counts needed.