Two levels exist, at which security in a big chemical product manufacturing plant can be maintained.
The first level at which security in a big chemical product manufacturing plant can be maintained is the one where technology is used. This can involve the use of CCTVs. Once people know that they are being watched, they are unlikely to steal from the company or do other things that contravene the security policy. But technology can also go to the level of how the plant itself is designed: for certain designs can facilitate crime, whereas other designs can discourage crime.
The second level at which security in a big chemical product manufacturing plant can be maintained is the one where human beings are used. The most obvious application here is that which entails the use of guards. But it can be taken a step further, to include the development of an intelligence system within the company: to ensure that, for instance, when some staff members plan to steal from the company, the whole conspiracy is nipped at that (planning) level. Actually with solid use of such intelligence and technology like CCTVs, you’d only need a handful of guards, mainly for cosmetic purposes – as the other mechanisms serve to ensure the actual security.