Flag or markdown-tag for "Dangerous behaviour"

Question

Looking at this questions led me to think that a flag should be introduced that marks questions / answers that describe dangerous behaviour, especially since the site promotes usage for amateurs.
Being a trained mechanic I know what bad things can happen during certain procedures, but I doubt an amateur could always guess all the dangers, same as I doubt that an answer on this site will always include all things that might possibly go wrong.

Of course it shouldn't be used to flag "use a hammer" because "one could hit one's fingers", but in the linked question people were discussing how to drill holes into a tank filled with diesel. 3500ltrs of diesel. So strict guidelines for its applications would need to be set.

The community needs a way to quickly close or even delete these questions, so that SE / HI can distance itself from such risky behaviour.
Also, if it is possible to win a lawsuit against mcdonalds for burning oneself with coffee, I see legal risks. You can probably imagine 100s of scenarios.

Alternative rougly based on Mołot's comment:
Similar to spoiler-tags(markdown-tags in this case), that hide the embedded area until explicitly clicked, like other websites have them:
Dangerous-tags
Before/When clicking they show a disclaimer "I understand the desribed behaviour is dangerous and that I alone bear the risk for my actions".

Additional info in relation to the posted duplicates:

1. The existing tag "dangerous" is a synonym of safety and used to inquire about wether things are dangerous, not to denote them as definetly being that.
2. The tag cannot be applied to answers (the "header" in this answer is actually just a custom text)

Answer 1

I agree with @BMitch in general. Specifically, I would recommend the following:

Question suggesting dangerous behavior

• Vote down the question
• Write an answer as to why the proposed plan is dangerous

Question asking about something that might be dangerous

• Don't vote the question down
• Write an answer explaining what might be dangerous (or a comment if the danger is not central to the issue being discussed)

Answer that recommends something dangerous

• Vote the answer down
• Post a comment as to why it is dangerous
• If the answer is very dangerous, post a competing answer explaining in detail (to gather supporting votes)

Answer suggesting something that might be dangerous

• If the answer is otherwise good, don't vote down
• Post a comment about the danger

Comment suggesting something dangerous

• Post a corrective comment

I tend to bold, and sometimes BOLD CAP my warnings. But then again, I can be a shouter.

Perhaps the most difficult situation is when the danger is a function of the skill level of the OP. Where the tone of the question makes it seem that the person is in a situation that a simple instruction will not easily make safe, I think the best approach is to politely suggest either help or avoidance, as in

The project seems to call for more advanced skills than you may have. Consider getting help from an experienced friend, or call in a pro.

If the OP is definitely over his head

This is a project that can be dangerous. It really should be left to a professional.

Answer 2

By closing or deleting the question, we are not giving the community the option to tell the OP that their question or answer is dangerous. In doing so, we are indirectly removing the danger flags from an activity and giving people on the internet less reasons to avoid a dangerous activity. I think the best option, as mentioned in the linked questions, is to make sure we clearly identify what is dangerous so people can learn from it, rather than destroying or concealing that knowledge.