If you breathe carbon monoxide in your rental unit, act quickly to protect your health and tenancy rights in Ontario. Tenants should know how to spot exposure signs, notify the landlord, and seek immediate medical care if needed. This guide explains practical steps for renters — from reporting the hazard and requesting emergency repairs to documenting evidence, asking for temporary accommodation, and involving local authorities or the Landlord and Tenant Board when repairs aren’t made. It also outlines which official forms and agencies to contact, how to track communications and expenses, and what to expect during inspections or hearings. Use these plain‑language steps to make informed choices, keep records, and reduce risk after a carbon monoxide incident.
What carbon monoxide is and why it matters
Carbon monoxide (CO) is a colourless, odourless gas produced by incomplete combustion of fuels such as natural gas, propane, oil, wood, or gasoline. High levels can cause headache, dizziness, nausea, confusion, loss of consciousness, and death. If you suspect CO exposure, treat it as an immediate health emergency and get fresh air and medical attention right away. [3]
Immediate steps for tenants after suspected exposure
- Get everyone out of the unit immediately and call 911 if anyone is unwell or unconscious.
- Notify the landlord or building manager right away, and follow up in writing (email or text) so there is a record.
- Seek medical assessment even for mild symptoms; ask for a written record of the visit and any recommended treatment.
Reporting the hazard and requesting emergency repairs
After immediate safety steps, send a written notice to your landlord describing the suspected CO exposure, listing symptoms, the time/date, and any actions you took. Keep copies of messages and delivery receipts. If the landlord does not arrange urgent repairs or a certified technician inspection promptly, tenants in Ontario can pursue remedies through the Landlord and Tenant Board under the Residential Tenancies Act, 2006. [1][2]
For guidance on safety obligations and common tenant actions in health emergencies, see the official tenant health and safety resources and practical repair guidance such as Health and Safety Issues Every Tenant Should Know When Renting and review emergency repair procedures in Emergency Situations and Repairs: Tenant Rights and Responsibilities.
Documenting evidence and expenses
Good documentation helps if you need an order, reimbursement, or temporary housing. Keep dated photos of detectors, vents, vents blocked or damaged appliances, medical reports, receipts for expenses, and copies of all messages with the landlord and emergency services.
- Take photos or video of the appliance, detector locations, and any visible damage or blocked ventilation.
- Save medical notes, pharmacy receipts, taxi or accommodation receipts, and repair invoices.
- Keep a short dated log of symptoms and conversations, including names and times.
Forms, filing an application, and what to expect
If your landlord does not act, tenants can apply to the Landlord and Tenant Board. The Board handles disputes about repairs, compensation, and temporary relocation when units are unsafe. See the Board for the correct application forms and instructions. [1]
Common official forms and when to use them
- Application to the Landlord and Tenant Board (tenant application forms) — use when the landlord won’t make urgent repairs or reimburse reasonable emergency expenses. Example: you requested an inspection and repairs for an appliance emitting CO but the landlord did not arrange service; file the tenant application to request an order for repairs and compensation.
- Supporting evidence package (photos, medical notes, receipts) — attach these when the Board allows evidence; keep organized copies for hearings.
- Request for urgent interim orders (if available) — ask the Board for temporary measures such as an order requiring the landlord to arrange temporary accommodation while repairs are completed.
Practical tenant example: If you emailed the landlord on Day 1 and received no reply, call the municipal gas/emergency service and document that action. If repairs are not completed within a reasonable time, file the tenant application with the Board and request costs for alternative accommodation and medical expenses if supported by receipts.
FAQ
- What are common early signs of carbon monoxide exposure?
- Headache, dizziness, nausea, confusion, flu‑like symptoms that improve when you leave the area, and loss of consciousness in severe cases.
- Who should I contact first: landlord, emergency services, or public health?
- If anyone is ill, call 911 immediately; afterward notify the landlord in writing and contact local public health or the appropriate emergency services for fuel appliances if suggested by the first responders.
- Can I withhold rent if my unit is unsafe due to carbon monoxide?
- Do not withhold rent without legal advice. Instead, document the hazard, ask for urgent repairs in writing, keep proof of expenses, and consider applying to the Landlord and Tenant Board for relief or rent abatement if appropriate.
How-To
- Leave the unit immediately and call 911 if anyone is sick.
- Notify your landlord in writing with date, time, symptoms, and actions taken.
- Document the scene: take photos, keep medical notes, and save receipts for expenses.
- Request urgent repairs or a certified inspection and ask for temporary accommodation if the unit is unsafe.
- If the landlord does not act, file the appropriate tenant application with the Landlord and Tenant Board and include your evidence.
Help and Support / Resources
- Landlord and Tenant Board - applications and forms
- Residential Tenancies Act, 2006 - Ontario e-Laws
- Health Canada - Carbon monoxide information
