A strainer (popularly known as floor drain cover or floor grating/grate) should always be used at all times to cover the floor drain.

Essentially a floor drain is a plumbing fixture installed in the floor with the objective of removing water area it. A floor drain usually is available in various shapes for example round, square or rectangular. Starting from 2 inches to 12 inches, most floor drains are 4 inches in diameter. Usually created from material such as metal or plastic, the gradient of the floor near a floor drain is normally sloped to let gravity do its job of draining the water around a floor drain.
Typically found near washrooms, water heater and the washer areas in residential areas, floor drains could also be spotted near commercial facilities such as basements, toilets, kitchens, refrigerator areas, shower and locker rooms and near swimming pools for commercial areas.
A strainer (typically referred to as floor drain cover or floor grating/grate) should always be used all the time to cover the floor drain.
The purpose of a floor drain cover (floor drain grate) is to ensure objectives like hair and pest don't get into the floor drain and clog the drains. A properly designed floor gratings (floor drain grate) always ensure safety to anyone near a floor drain.
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