How a hospital works: departments, people and the equipment they depend on

Place any service call on the map of the hospital - which department, who the user is, what the patient depends on - and set its priority and your first action accordingly.

Why the engineer needs the map

A hospital is not a building full of machines. It is a set of departments, each with its own patients, its own staff and its own rhythm, connected by corridors, gas pipes, cables and a constant flow of people. The same fault means very different things in different places. A blank screen on an ultrasound unit in an outpatient clinic means a rescheduled appointment. A blank screen on a monitor in the intensive care unit means a nurse who can no longer see whether a patient's heart is beating.

The engineer who knows the map makes better decisions before touching a screwdriver. You know which call to answer first, who to ask for the facts, which door you may not open without permission, and what backup the department has if you take the device away. You also know who will be affected by your repair: not just the person who called, but the patients scheduled for the rest of the day.

This lesson gives you that map. It is general: hospitals differ by country, size and specialisation, and many small hospitals combine several departments in one area. Learn the logic, then walk your own sites and fill in the details.

The main departments and what stands in them

Group the hospital by what happens to the patient. Some areas keep patients alive, some find out what is wrong with them, some treat them, and some support everyone else. The list below is a starting point for your own asset map; the equipment named is typical, not complete.

• Emergency department: the front door. Patient monitors, defibrillators, transport ventilators, suction, X-ray nearby, point-of-care blood gas and glucose meters. Everything must work immediately, at any hour.
• Intensive care (adult, paediatric, neonatal): the highest density of life-support equipment - ICU ventilators, central monitoring, infusion and syringe pumps, dialysis or filtration machines, incubators and warmers in neonatal units.
• Operating theatres and anaesthesia: anaesthesia machines, monitors, electrosurgical units, operating tables and lights, endoscopy towers, mobile C-arms, warming devices. Scheduled work, but a failure during surgery cannot wait.
• Imaging (radiology): X-ray, CT, MRI, ultrasound, mammography, fluoroscopy and angiography, nuclear medicine. High-value equipment, radiation and magnetic-field safety zones, tight appointment schedules.
• Cardiology: ECG machines, Holter recorders, stress-test systems, echocardiography, the catheterisation laboratory.
• Laboratory: biochemistry, haematology, immunoassay, coagulation, microbiology, blood bank refrigerators. Results drive decisions everywhere else in the hospital.
• Wards: beds, monitors, infusion pumps, suction, oxygen flowmeters, nurse call. Lower acuity, but the largest number of devices.
• Support services: sterilisation department (washers, autoclaves, low-temperature sterilisers), medical gas plant, water treatment for dialysis and the laboratory, mortuary refrigeration, kitchens and laundry.

Who uses the equipment, and who owns the decision

Every device has several people around it, and you need to know which one to talk to for which question. The clinician - doctor, nurse, radiographer, laboratory scientist, perfusionist - is the user. The user knows what the device was doing, what was set, what the patient looked like, and what alarm appeared. The user decides whether a patient can be treated without the device. You do not make that decision.

The head of department or the nurse in charge owns the schedule and the backup. Ask them whether the department can manage without the device for an hour, a day or a week, and whether they have a spare. Do not rely on the person who phoned to know this.

Behind the clinical staff stand other specialists you will work with. The medical physicist is responsible, in many countries, for radiation dose and image-quality testing of X-ray, CT, nuclear medicine and radiotherapy equipment. The infection prevention team sets the rules for cleaning, isolation rooms and what you may carry in and out. The sterilisation department reprocesses instruments and some device parts. The risk or quality manager receives incident reports. Procurement and the finance department decide whether a repair is paid for or the device is replaced.

Finally, the clinical (biomedical) engineering department, which may be you, keeps the inventory, the service history and the planned maintenance schedule. In an external service company you serve this department; in a hospital you may be it. Either way, every job you do should end up in its records.

Criticality: not every call is equal

A useful way to rank devices is to ask two questions. First: if this device fails while in use, what happens to the patient? Second: is there an immediate alternative? A ventilator in the ICU fails both tests badly - the patient can be harmed in minutes, and the backup is a manual bag squeezed by a nurse. A dental chair fails neither - the procedure is postponed.

Most hospitals and service organisations sort equipment into roughly three groups, whatever names they use locally. Life-support and resuscitation devices: ventilators, anaesthesia machines, defibrillators, infant incubators, dialysis machines, heart-lung machines, infusion pumps for critical drugs. Diagnostic and monitoring devices whose failure delays or misleads treatment: monitors, imaging, laboratory analysers. Supporting devices whose failure is an inconvenience: examination lights, beds, therapy units.

Two words matter here: 'misleads' and 'delays'. A device that stops completely is often less dangerous than one that keeps working and gives a wrong number. A dead monitor is noticed at once; a monitor that reads oxygen saturation a few percent too high may go unnoticed for days. This is why later lessons spend so much time on what each measurement means. The priority you give a call should reflect both the consequence of the failure and the chance that nobody has noticed it yet.

Rules of the floor

Clinical areas have rules that protect patients and staff, and an engineer who breaks them loses the trust of the department quickly. Learn them before you need them.

• Report to the nurse in charge when you arrive in a clinical area and before you leave. Never take a device away without telling someone who is responsible for it.
• Operating theatres have clean zones, dress codes and doors that stay closed. Enter only in theatre clothing, with permission, and never cross the sterile field around the patient.
• Isolation rooms are marked at the door. Follow the PPE instructions on the sign, and ask the nurse before entering. Lesson 7 covers this in detail.
• Radiation areas: do not enter an X-ray, CT, fluoroscopy or nuclear medicine room while an exposure may be made or a source is in use. Respect warning lights and signs, and wear a dosimeter where local rules require one.
• MRI: on superconducting scanners - almost all clinical MRI - the magnetic field is always on, even when no scan is running. Never enter the magnet room (Zone IV) without screening by MRI staff, and stay under their supervision while you are there. Never take tools, gas cylinders or equipment in unless they are labelled MR Safe, or MR Conditional and used within the conditions on the label.
• Patient privacy: do not read, photograph or copy patient data from screens or printouts. If a log or image you need for diagnosis contains patient data, follow the hospital's procedure for handling it.
• Never service, open or calibrate a device while it is connected to a patient. The patient is moved to a backup by clinical staff first.

How a request travels, and where it goes wrong

A typical request starts with a nurse noticing something, telling the nurse in charge, who phones engineering or opens a ticket. By the time it reaches you, the message is often three sentences shorter than the original: 'Monitor in bed 4 not working'. Which monitor, which parameter, what happened, is the patient still on it? You cannot set a priority on that message alone.

Build a habit of completing the request before you leave the workshop: the asset number or serial number, the exact location, the name and phone number of the person who saw the problem, what the device was doing, whether a patient was connected, and whether the department has a backup in use. Five minutes on the phone saves an hour of walking around a hospital looking for the right device.

At the other end, the job ends not when the device works, but when the user knows it works. Return the device to a named person, tell them what was found and done in plain language, and record it. A device left silently in a corridor with a sticky note is a device nobody trusts.

On-site checklist

• Walk each department you serve and list the life-support devices and where their backups are kept.
• Know the name and phone number of the nurse in charge or department lead for each area.
• Before leaving for a call: asset number, location, contact, patient connected or not, backup in use or not.
• Report in and out of every clinical area; never remove a device without telling a responsible person.
• Learn the local rules for theatres, isolation rooms, radiation areas and the MRI zone before you need them.
• Hand the repaired device back to a named person and record the job in the service history.

Check yourself