Because the most likely reason somebody needs help in a bathroom is that they have fallen - and a cord they cannot reach from the floor is useless at exactly that moment.

Bathrooms are where falls happen: wet surfaces, transfers on and off fixtures, and people who may be unsteady. A person on the floor cannot stand to reach a wall button.

So the cord runs from the ceiling to within a short distance of the floor, and that length is specified by the governing standard rather than chosen.

A cord that has been shortened, knotted, tied up out of the way or looped over the unit is a serious defect. It happens constantly - cleaners and staff tidy it, or it is shortened because it is in the way - and it removes the whole function without any indication that anything is wrong.

Routine checks should specifically confirm the cord's length and free hang, and staff should understand why it must not be moved. This is a recurring inspection finding in care settings.

Within reach of the WC, the shower or bath, and the open floor area - which usually means near the fixture rather than by the door.

The positions where somebody may need help are the ones they use: sitting on the WC, in or getting out of the shower, and anywhere on the floor after a fall.

A cord by the door is easy to install and serves none of those well.

The usual arrangement places the unit so the cord hangs adjacent to the WC and within reach of the shower area, with the floor coverage that follows. In larger accessible bathrooms more than one may be needed.

Avoid positions where the cord will be caught by a door, a shower curtain or a hoist track, since a cord that gets in the way is a cord that will be tied up.

Coordinate with the sanitaryware layout at design stage. Positioning decided on site after the fixtures are in usually produces a compromise, and the local accessibility standard may specify the position explicitly.

A rating appropriate to the zone in which it is installed, which for a ceiling position in a shower room means resistance to splashing and steam at minimum.

Wet areas are divided into zones by electrical regulations, with requirements depending on proximity to the bath or shower. A ceiling-mounted unit is usually in a zone requiring protection against splashing water, and above a shower it may require more.

Steam is the underestimated factor. A unit that resists splashing may still admit moist air that condenses inside, corroding contacts over time and producing intermittent faults - which in a life safety device is unacceptable.

The zone requirements and permitted equipment are set by the local electrical regulations, which differ between jurisdictions, and the installation must comply.

Specify sealed units suitable for the position, and include them in periodic inspection - a unit with moisture inside gives no external sign until it fails.

Washable or replaceable cords, changed when soiled or worn - because they are handled with wet and often soiled hands.

A bathroom pull-cord is touched by people who are wet, and in care settings by people who may have soiled hands. It is a known infection control concern.

Wipeable plastic-coated cords can be cleaned and are preferable to fabric in most healthcare settings. Where fabric cords are used, they should be laundered or replaced on a schedule.

The bangles are handled most and should be smooth, sealed and cleanable.

Replacement should be simple - a cord that requires the ceiling unit to be dismantled will not be changed as often as it should be.

Include cord condition in routine checks: soiling, fraying, discolouration and length. Replacing a cord is inexpensive; a visibly grubby cord in a care setting is both a hygiene issue and a signal about the standard of maintenance generally.

A high-contrast colour specified by the governing standard - usually red for emergency call in many jurisdictions, but this differs and must be checked.

The purpose is that the cord is findable quickly by somebody in distress, including someone with limited vision, so contrast against the background is the underlying requirement.

Many accessibility standards specify a particular colour for accessible WC emergency alarms, and healthcare standards may specify colours distinguishing call types. Those conventions differ between countries, and applying the wrong one is a common error on international projects.

Consistency within a building counts for as much as the specific colour - the same colour should mean the same thing everywhere.

Bangles should contrast with the cord as well as with the background, and their positions are usually specified so that one is reachable from the floor and one from a seated position.

Confirm the requirement in the applicable standard before ordering, since cords and bangles are supplied in several colours.

No. They look similar and are frequently confused, but they are different systems with different response obligations.

A nurse call pull-cord in a patient bathroom is part of the nurse call system, and the response is from care staff.

An accessible WC emergency alarm is required by accessibility regulation in public and commercial buildings, and the response is from whoever is responsible for the premises. It usually has its own indicator outside the WC and its own panel, and it is not connected to a nurse call system.

The confusion causes real problems. A building with an accessible WC alarm that rings somewhere unattended does not meet its obligation, and staff who believe it is part of another system may not respond.

Be explicit about which system is being installed, where each annunciates, and who responds - and make sure the people responsible know. Testing should cover the response, not only the device.

On the same documented schedule as the rest of the system, with the cord's length and free hang checked at every routine room inspection.

Functional testing operates the cord and confirms the call annunciates correctly, the over-door light operates, and it resets properly.

The more frequent check is physical and takes seconds: is the cord hanging free, at full length, undamaged, and are the bangles present. That check should be part of routine room checks rather than only the periodic test, because the failure mode - a cord tied up or shortened - can occur at any time and gives no other indication.

Record the results. In regulated settings this is part of the evidence of safe operation.

Brief cleaning and housekeeping staff specifically. They are the people most likely to tie a cord out of the way, and most likely to notice a damaged one - so they are both the risk and the best early warning.