Section 1:
When KA complies with OHSAS, they are basically try to make their operation safe to their employees. If we zoom down to the smell issue KA, this will be like their storage area have to be ventilated etc by using local exhaust ventilation (LEV), etc. So, as far as OHSAS is concerned, the smell in their company has to be ventilated out to safeguard their employee (hence the smell if any). If they are supposed to open a scheduled waste drum that emit odour in their company, they are supposed to wear protection and work in ventilated area to ensure the safety of their employees by reducing the inhaling/contact with chemicals. This standard also call for monitoring of dangerous chemicals by collecting sample from LEV and blood tests (if applicable) among employee but it also boil down to the health and safety of the employees.

Usually this standard comes together with ISO14001. In ISO14001, it is about safe guarding the environment by preventing release to the environment. This is standard that will talk about the smell. However, there is a caveat here. In both standards, it is all about management of the risks. In other word, a company is supposed evaluate the risk and come out with action to prevent accident release/injuries and containment measures. There is always probability of accidental release. An action can be very high risk, but it can be assigned with a low probability, thus giving a low risk quadrant in the assessment. In this kind of situation, you can still operate by preparing containment measures. However, when accident happen, whether these actions will be successfully employed, nobody can really know, especially when it comes to accidental release to the environment. When come to smell, it is really hard to comply and easy to deny responsibility. 

Section 2:
For their customers (industries), when complying with ISO14001, they are required to dispose scheduled waste properly. In this standard, there are scheduled waste code. A company is supposed to identify their waste and sent to authorized waste management like KA for disposal. Their responsibility usually end here (a collection ticket from KA can basically shut an auditor up). However, in the process, there are many codes such as SW421 mixed chemicals where a company can dispose a mixture of scheduled waste in a waste drum and send to KA for burning. The problem is, no one actually open up a drum and check the content 1 by 1. You can throw chlorine, fluoride etc inside and nobody know. They all end up in incinerator. That is why I said, it depends on what is being burnt as well.
These 2 standards are more than above, not limited to above aspects. But for this discussion, I think above few examples should be enough.