Coal mining generates significant adverse environmental impacts. Historically, coal mining has been a very dangerous activity and the list of historical coal mining disasters is a long one. Underground mining hazards include suffocation, gas poisoning, roof collapse and gas explosions.
The term 'OVD' (Optically Variable Device) is used to describe both laser generated hologram images and electron beam generated images. These optically variable devices are created in highly-secure facilities and are at the forefront of overt asset and brand protection programmes.
Open Value Subscription (OVS) is a low cost easy way to license all the latest Microsoft software via one simple three year rental agreement. OVS is specifically designed as the optimum licensing solution for companies with 5 to 250 desktops. At the end of the three year agreement customers have the choice to either extend the agreement, buy out the software or discontinue usage.