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How to install a smoke alarm

Getting someone else to do a job for you can be costly. But with the right approach you can do a lot by yourself. You’ll save time and money by using the handy step-by-step instructions that you’ll find on the SKIL website. These step-by-step instructions are divided into categories relating to the different kinds of jobs in and around the home, and give you clear, A to Z explanations.

Just click on one of our step-by-step instructions and you’ll be able to get started right away!

  1. How does a smoke alarm work?

    A smoke alarm produces an alarm signal as soon as smoke or gas is detected, which means it responds indirectly to fire. There are also detectors that respond to heat or light. For home use, smoke alarms are the most commonly used type.

  2. In case of alarm

    • Call the fire brigade or the emergency number.
    • Close all doors and windows in the room where the fire has broken out.
    • Don’t open any closed doors if they feel warm.
    • Try to help everybody to escape safely from the source of the fire.
    • Hold a wet cloth over your mouth and nose. Don’t inhale any smoke.
    • Stay low against the floor, that’s where the temperature is lowest and there is the lowest concentration of smoke and poisonous gases.

  3. Unsuitable places for a smoke alarm

    There are a number of places where it’s best not to install a smoke detector because it may give frequent false alarms:
    • Places where steam is produced, such as in the shower/bathroom or kitchen.
    • Near a ventilation opening, heating appliance or radiator. In these places air convection may prevent any smoke from reaching the smoke alarm.
    • In the garage, where exhaust gases may cause a false alarm.
    • Close to lamps. The smoke alarm can quickly become contaminated by dust as a result of air convection due to the heat from the lamp. A smoke alarm should be installed at least 30 cm away from a lamp.

  4. Smoke alarm on the escape route

    Smoke alarms should be installed on the escape routes in the house. Then you can always be sure which route you can use to leave the house. The best place to install a smoke alarm is on the ceiling. In practice, smoke detectors are installed in rooms like the living room, hall and landing, attic stairs, back kitchen and/or adjoining garage. If you have a house with more than one floor, it’s a good idea to install a smoke alarm on each floor. It’s important that you can hear an alarm signal from the smoke detectors in the bedrooms. If you have several smoke alarms, it’s best if they are connected together.

  5. Installation

    Remove the cover and hold the smoke alarm against the ceiling. Mark out the holes to be drilled on the ceiling. Then drill the holes to the required depth using a 6 mm masonry or wood drill bit and insert the wall plugs in the holes. If the ceiling is made of hollow panels, you need to use special plugs. Then screw the smoke alarm into place. If the smoke alarm is mains-powered you need to connect it to the mains supply following the instructions. The best place to fit the smoke alarm is in the center of the room.

  6. Activating the smoke alarm

    Place the batteries in the battery holder and replace the cover. Use the test button to check that the smoke alarm is working. Don’t forget to replace the batteries when necessary! Every smoke alarm has a warning signal to show when the batteries are nearly empty.

  7. Step tip

    Don’t throw used batteries away with the rubbish, but hand them in at a recycling point. Or use good-quality rechargeable batteries.


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