The "safety" in this case is relative. What is called "safe sex" can greatly reduce the chance of getting STDs, which of course makes such practices worthwhile to follow, but you can't really reduce it to zero. In other words, following safe practices is much better (much safer) than not following them.
The risk of STDs are still there but otherwise fine.
Eliminate the risk? No. But it will greatly REDUCE the risk.
The Kaposis Sarcoma is related to hiv and herpes virus. So the risk factors are if you already have one of these two viruses or if you are sexual active without using protection against these stds.
Controls are designed to reduce or eliminate risk.
allergic reactions,risk of transmission of stds and infectious diseases.
I presume you mean 'during sex'. You are at risk of pregnancy and of STDs if he is a carrier. In future insist on a condom. Meanwhile, go swiftly to a sexual health clinic and ask their advice.
There is a risk of STDs, but otherwise it is not.
reduce or eliminate risk
If your protection fails or you do not use protection you run the risk of becoming pregnant
eliminate the risk altogether
You must know who is at risk, and when, before you can control or eliminate the risk.
Controls are designed to reduce or eliminate risk.