A Complete Guide to Preventing Gas Leaks and Carbon Monoxide Poisoning in Rental Apartments

While it's easy to think "it can't happen in my apartment," rental properties face particular risk in certain situations. Understanding the main causes is the first step in prevention.

Poor Connections Around Gas Stoves The gas hose connecting the stove to the gas valve deteriorates over time, developing cracks and loose connections. Be especially cautious if you connected the stove yourself after moving in, or if the hose has been in use for many years. Gas hoses typically need replacement every 5–6 years, and any visible cracks or deformation require immediate replacement.

Deteriorated Gas Pipes and Equipment In apartments and older rental properties, the gas pipes within the building itself may be deteriorating. In properties over 30 years old, gas pipes within walls or under floors may be corroded. It's advisable to ask the management company to confirm the inspection history of gas equipment before moving in.

Checks After an Earthquake When an earthquake of magnitude 5 or stronger occurs, the gas meter's automatic shutoff system activates. While a reset operation is necessary, first always check whether there is any gas odor inside the apartment. Since there is a possibility the gas pipe may have cracked, if you detect an unusual smell, do not attempt to reset the meter—contact your gas company instead.

The Dangers and Symptoms of Carbon Monoxide Poisoning

Carbon monoxide (CO) is a colorless, odorless gas that cannot be detected by human senses—even when present. This is its greatest danger.

Carbon monoxide is produced when gas or heating oil undergoes incomplete combustion. Concentrations rise when you use a stove in a sealed room for extended periods, or when you use gas equipment without adequate ventilation.

Stages of Carbon Monoxide Poisoning Symptoms

• •Mild: Headache, dizziness, nausea (often mistaken for a cold rather than recognized as gas poisoning)
• •Moderate: Severe headache, impaired judgment, physical weakness
• •Severe: Loss of consciousness, and in the worst case, death

Symptoms often worsen undetected during sleep, making ventilation before bed and alarm installation essential. Pets and young children develop symptoms faster than adults, so households with family members should be particularly cautious.

Types of Alarms Required in Rental Properties and Where to Install Them

Certain alarms are legally mandated for rental properties by law or local ordinance. Always verify their existence and condition upon move-in.

Residential Fire Alarms The Fire Services Act mandates their installation in all residences. They must be installed in bedrooms and on staircases in the floor where bedrooms are located. In rental properties, landlords typically bear the installation responsibility, though this varies by region and property. For battery-powered models, batteries last approximately 10 years; the entire unit must be replaced when batteries expire.

Gas Alarms Gas companies and local authorities recommend these alarms. They are most effective when installed near the gas stove or hot water heater. City gas is lighter than air, so install near the ceiling; LP gas is heavier than air, so install near the floor. The effective lifespan varies by product, but 5 years is the typical guideline.

Carbon Monoxide Alarms Combination gas and CO alarm units are available commercially. They are especially effective in rooms with oil stoves or oil heaters. When installed alone, they are most effective when placed near your sleeping area and near oil appliances.

Essential Safety Inspection Points When Moving In

When moving into a new rental property, check the following items before your belongings are moved in. If problems are discovered later, responsibility becomes unclear once you've moved in.

Checking Alarms

• •Fire alarms are installed in all rooms (bedrooms and staircases)
• •Test buttons work when pressed
• •Check manufacturing date and expiration date labels (request replacement from management if expired)

Checking Gas Equipment

• •Gas stove hoses show no cracks or deformation
• •Gas valves open and close smoothly
• •Hot water heater installation year and inspection history (confirm with management)
• •Exhaust fans and ventilation ports function properly

Document Issues Before Move-In If you discover any problems, photograph them and report to the management company in writing or email, requesting confirmation. Verbal-only reports may lead to disputes later.

Correct Steps to Take When You Discover a Gas Leak

If you smell gas, panic and incorrect actions can cause fire or explosion. Stay calm and follow these steps carefully.

1. Do Not Use Fire or Touch Switches
2. •　Even turning electrical switches on or off can ignite gas-filled spaces. Avoid touching light switches too.

1. Close the Gas Valve
2. •　Close the main gas valve on the stove. If accessible, also close the main valve inside the meter box.

1. Open Windows and Doors for Ventilation
2. •　Open windows and doors to let gas escape outside. Do not operate the exhaust fan as it requires using an electrical switch.

1. Leave the Building and Call Your Gas Company
2. •　Exit the building first, then call your gas company's emergency line (for city gas, contact your regional gas company; for LP gas, contact the supplier managing your gas bottle). Use your mobile phone outside the building.

1. Wait for Technician Confirmation Before Reset
2. •　Do not open gas valves or reset the meter yourself until a gas company technician has verified safety.

Important Precautions When Using Oil Stoves and Heaters in Winter

Many rental properties prohibit oil stoves, but if yours permits them, proper management is essential. Carbon monoxide poisoning accidents are concentrated during winter months.

Ventilate 1–2 Times Per Hour While an oil stove is in use, open a window for a few minutes every hour. Using it for extended periods in a sealed room, even when it's cold outside, causes CO concentrations to spike rapidly.

Always Extinguish Before Sleep and When Leaving Home Never sleep or leave home with an oil stove running. For models without timers, build a pre-sleep routine that includes turning off the stove to prevent forgetting.

Storage and Quality of Heating Oil Using degraded heating oil (discolored or contaminated) promotes incomplete combustion. Do not use leftover heating oil from previous seasons; use your local gas station's used oil disposal service instead.

Install a Carbon Monoxide Alarm I strongly recommend installing a carbon monoxide alarm in rooms with oil stoves. They cost around ¥3,000–¥6,000 and are a worthwhile investment for protecting your life.

How to Report Issues to Your Landlord or Management Company and Request Repairs

If there are problems with gas equipment or alarms, tenants should not attempt repairs on their own. Report to the management company or landlord and request repairs.

What to Include in Your Report

• •Date and time of discovery
• •Specific location and description ("the gas hose in the kitchen has a crack," etc.)
• •Attach photos if available

Keep Written Records via Email or Letter Avoid reporting by phone alone; use email or messaging apps that create a written record. In cases of delayed response, you may use certified mail, but first try making your request through sincere, repeated communication.

In Cases of High Urgency If there is a risk of gas leaks or carbon monoxide poisoning, contact the gas company directly in parallel with notifying the management company. In life-threatening emergencies, do not wait for management company approval.

A safe home is built on the awareness and actions of residents themselves. Daily habits like checking alarms and proper ventilation prevent major accidents. Take the time to review your home's safety during moving season or seasonal changes.

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