Using CO Alarms: Tenant Safety in Germany

In older buildings, leaking flue paths, outdated heating devices or poorly maintained chimneys can increase the risk of carbon monoxide (CO). For tenants in Germany it is important to install CO alarms correctly, document incidents systematically and inform the landlord in writing. This article explains practical steps to take, deadlines to observe, how to collect evidence securely and which courts and legal bases are relevant.^[1] Read the guide to act quickly in an emergency and to protect your rights under the BGB.

Recognising CO risks and why documentation matters

Carbon monoxide is odourless and can cause drowsiness, headaches or nausea at low concentrations; at high doses it can be life-threatening. For judicial or extrajudicial clarification, comprehensive documentation is often decisive: date, time, measured values, photos of the heater and the alarm placement, and communication with the landlord.

How to install CO alarms correctly

Place CO alarms according to the manufacturers instructions in sleeping and living rooms, not hidden behind furniture or directly next to cooking appliances. Check batteries regularly and keep a log of tests.

• Install alarms according to the manual at head height of a standing person, but away from direct exhaust sources.
• Record installation date, model and serial number of the alarm.
• Keep a test log with regular function checks and store photos as evidence.

Step-by-step documentation in case of an incident

If an alarm sounds or you notice symptoms: leave the flat, call for help (emergency number 112 if there is danger) and inform the landlord in writing. Record measured values, medical certificates and witness statements.

• Report the incident to the landlord in writing without delay and request confirmation.
• In acute danger call the emergency services (112) immediately and document the response.
• Save photos of the alarm, heating systems and any visible defects.

Rights and obligations — brief overview

Landlords must hand over and maintain the rented property in a condition suitable for contractual use. If CO causes a hazard, tenants may have defect-related rights such as rent reduction or claims for remediation.^[1]

If the landlord does not respond

If the landlord does not act promptly, follow up in writing, set deadlines and document possible substitute measures. Before taking unilateral action, check legal consequences and seek advice; the local court (Amtsgericht) is competent for tenancy disputes.^[2]

FAQ

Who pays for the CO alarm?

It can be contractually agreed who is responsible for purchase and maintenance; if alarms are required by law, the landlord usually bears the costs.

Can I reduce the rent if no alarm is present?

If necessary protection is missing and there is a health risk, a rent reduction may be possible; documenting the defect and notifying the landlord are prerequisites.^[1]

Where do I turn in case of acute poisoning risk?

In acute danger call emergency services (112) immediately and leave the dwelling; afterwards inform the landlord and document the incident.

How-To

1. Immediate action: leave the flat and call 112 if the alarm sounds.
2. Documentation: record date, time, measured values, photos and any medical records.
3. Defect notice: send a written notification to the landlord requesting remediation within a deadline.
4. Legal steps: if there is no response prepare documents for a possible claim at the local court and seek legal advice.^[2]

Help & Support / Resources

• Bürgerliches Gesetzbuch (BGB) — Gesetze im Internet
• Federal Court of Justice (BGH) — information on decisions
• Federal Ministry of Justice — official publications

1. [1] Bürgerliches Gesetzbuch (BGB) §§535–580a — Gesetze im Internet
2. [2] Zuständigkeit der Amtsgerichte — Justizportal
3. [3] Federal Ministry of Justice and Consumer Protection — official publications