Dialysis is not safe. Accidents will happen unexpectedly.
The nurse is the last line of defense. These pages are your preparation.

Vigilance — Critical Thinking — Rapid Action

Chlorine/Chloramine Monitoring – Dialysis Safety

Back to Safety Series Home

The Key Concept

"Chlorine MUST be 0.0 mg/L after Carbon Tank #2. If it rises to 0.1 mg/L, there will be NO notification during the dialysis session — but on the NEXT session, patients may reflect unusual symptoms as tired, not in good style as usual."

The Patient is the Alarm — Not the Machine

Action Levels When to Act

Chlorine Level	Interpretation	Patient Impact	Action
0.0 mg/L	Safe	No symptoms — patient is safe	Continue routine monitoring
0.0 – 0.05 mg/L	Trace — ALERT	No immediate symptoms — but risk is present	Investigate immediately • Check carbon tanks • Check flow rates • Check incoming chlorine levels
0.05 – 0.1 mg/L	WARNING — Carbon exhaustion	No symptoms during session But patient may feel tired NEXT session	Immediate action • Carbon tanks may be exhausted • Call biomedical team • Do NOT use water for dialysis
> 0.1 mg/L	CRITICAL — Hemolysis risk	Hemolysis — RBC destruction Anemia, fatigue, pallor, dark urine	EMERGENCY ACTION • Stop using water immediately • Flush carbon tanks • Replace carbon media • Notify MOH and infection control

The Hemolysis Pathway How Chlorine Destroys Red Blood Cells

From Chlorine Exposure to Hemolysis

Chlorine in Water Passes Through RO Membrane Enters Dialysate Crosses Dialyzer Membrane Oxidizes Hemoglobin RBC Rupture → Hemolysis Anemia + Hyperkalemia

The dialyzer membrane offers NO defense against chlorine — it passes directly into the patient's blood.

Why Chlorine is So Dangerous The Physiology

Oxidizes Hemoglobin

Chlorine oxidizes hemoglobin — converting it to methemoglobin. Oxygen-carrying capacity is lost.

Hemoglobin → Methemoglobin (cannot carry oxygen)

Destroys RBC Membrane

Chlorine damages the red blood cell membrane — causing it to become fragile. RBCs rupture prematurely.

RBC rupture → Hemoglobin released into plasma

Hyperkalemia

Ruptured RBCs release intracellular potassium. Massive K⁺ release → hyperkalemia.

Each RBC releases ~120 mmol/L K⁺

Anemia

Hemolysis leads to sudden anemia. Hemoglobin drops rapidly.

Patient becomes pale, weak, short of breath

Clinical Presentation What the Nurse Sees

Unexplained Fatigue

"I just feel tired — not my usual self."
Often appears the NEXT session, not immediately.

Pallor

Patient looks pale — skin and mucous membranes are lighter than usual.
Hemoglobin is dropping.

Shortness of Breath

Dyspnea on exertion — patient gets short of breath with minimal activity.
Due to decreased oxygen-carrying capacity.

Hypotension

Blood pressure drops — due to decreased blood volume from hemolysis.

Dark Urine

Hemoglobinuria — urine appears dark or tea-colored.
Hemoglobin is excreted in urine.

Sudden Anemia

Hemoglobin drops significantly — often > 1 g/dL in a single session.
THIS IS A RED FLAG.

The "Next Session" Phenomenon — Why Symptoms Appear Late

If chlorine rises to 0.1 mg/L, there will be NO notification during the dialysis session.

The patient may feel completely fine during dialysis. But on the NEXT session, they will come in saying:

"I feel so tired. I'm just not in good style as usual."

🧠 Think: "Why is this patient so tired? Why do they look pale?"
📊 Check: Chlorine logs for the past 3–5 days
🩸 Check: Recent hemoglobin levels — is there a drop?
🛑 Act: If multiple patients have these symptoms — SUSPECT CHLORINE

The Carbon Tank System The Critical Defense — And Its Vulnerabilities

Carbon Tank #1

First line of defense. Removes 80-90% of chlorine/chloramine from incoming water.

If chlorine is high BEFORE Carbon Tank #2 — Carbon Tank #1 is NOT functioning.

Test Point: After Carbon Tank #1
If chlorine is high here — Carbon Tank #1 needs regeneration or replacement.

Carbon Tank #2

Final defense. Removes the remaining 10-20% of chlorine/chloramine.

Chlorine MUST read 0.0 mg/L AFTER Carbon Tank #2.

Test Point: After Carbon Tank #2
✅ MUST = 0.0 mg/L — MOH tests here

Power Supply Vulnerability — A Critical Weakness

Most water treatment units are NOT connected to UPS (battery backup) or generators.

If electricity fails during filter regeneration — the regeneration process will not happen — and the filters will remain exhausted.

No UPS/Generator
Most units rely on municipal power. If power fails during regeneration — the process stops.

Regeneration is Time-Sensitive
Carbon tanks require regular regeneration to maintain effectiveness. Missed regeneration = exhausted carbon = chlorine passes through.

Nurses Must Be Aware
If power has been interrupted recently — check chlorine more frequently. Carbon may not have been regenerated.

Biomedical Team Must Verify
After any power interruption, the biomedical team must verify regeneration occurred. If not — regenerate manually or replace carbon media.

The Nurse's Role Early Detection & Action

Test Chlorine Every Shift

Test AFTER Carbon Tank #2. MUST read 0.0 mg/L.

If chlorine is present — DO NOT use water for dialysis.

Test BEFORE Carbon Tank #2

Test after Carbon Tank #1.

If chlorine is high here — Carbon Tank #1 is NOT functioning.
Needs regeneration or replacement — call biomed immediately.

Check Power Supply Status

Has there been a power interruption?

If power failed recently — check chlorine more frequently.
Regeneration may not have occurred.

Ask Patients — Every Session

"How do you feel today? Tired? Weak? Dizzy?"

Patients often notice changes before we do.
If multiple patients report fatigue — SUSPECT CHLORINE.

Monitor Hemoglobin Trends

Check hemoglobin levels regularly.

Sudden drops > 1 g/dL = RED FLAG.
Could indicate hemolysis from chlorine exposure.

Notify Biomedical Team

Report immediately if:
• Chlorine is > 0.0 mg/L
• Multiple patients have unexplained fatigue or pallor
• Hemoglobin levels drop suddenly

Do NOT wait — patients are at risk.

Case Example Real Scenario

✅ Normal Chlorine — Patients Feel Well

⚠️ Chlorine Rising — Patients Feel Tired

Day	Chlorine (After Carbon #2)	Patient Symptoms	Action
Monday	0.00 mg/L	All patients feel well	Routine
Tuesday	0.00 mg/L	All patients feel well	Routine
Wednesday	0.05 mg/L	No symptoms during session	⚠️ Alert — investigate carbon tanks
Thursday	0.08 mg/L	No symptoms during session	⚠️ Warning — carbon exhausted
Friday	0.10 mg/L	Multiple patients: "I'm so tired. I'm not myself." "I feel weak and dizzy." Pallor noted in 3 patients	🚨 CRITICAL Stop using water. Flush carbon tanks. Call biomed immediately.
Saturday	0.00 mg/L	Patients gradually improving	Carbon replaced — water safe

What happened? Carbon Tank #1 was exhausted due to a power interruption during regeneration. The nurse noticed the pattern — multiple patients with unexplained fatigue and pallor — and recognized the "next session" phenomenon.

By checking chlorine logs, the nurse confirmed the rise and took immediate action.

0.0 is the ONLY Acceptable Number

Chlorine/chloramine is a silent killer.

0.1 mg/L — no symptoms during dialysis. But on the NEXT session — patients will feel tired, weak, and "not in good style."

> 0.2 mg/L — hemolysis. Red blood cells are destroyed.

The machine will NOT alarm. The patient's symptoms are the alarm.

Test chlorine every shift. Ask patients about their symptoms. Trust the pattern.

When patients feel tired — suspect chlorine. When patients are pale — check hemoglobin. When multiple patients are affected — ACT.

✍️ Author: Ahmed Mohmad Rashyd Musleh Registered Staff Nurse