Raise a concern at work without making it worse

Help me raise a concern at work.

What's happening: [facts, with dates]
Who's involved: [roles rather than names is fine]
What I've tried: [anything]
How serious it is: [e.g. annoying, affecting my health, about safety or harassment]
What I want to happen: [outcome]

Ask me up to 3 short questions first if anything important is missing. Wait for my answers.

Then:
1. Whether to raise it informally first. Acas says that's usually a good idea, unless it's very serious, for example harassment or whistleblowing.
2. What to say in an informal chat with my manager or HR.
3. A short follow-up email confirming what I raised.
4. A simple record template: date, what happened, who saw it, how it affected me.
5. What happens if informal doesn't work: a formal grievance, and where to read about it on Acas.

This is help with wording and preparation, not legal advice; point me to Acas (helpline 0300 123 1100, Mon–Fri 8am–6pm) or GOV.UK for my rights, and to Citizens Advice or a union if I need someone on my side. Only use what I've told you, leave blanks for anything I haven't given, and don't invent facts, dates or results. UK English.

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