The Hydrosense ONE Ultra detects Legionella serogroup 1 in Thailand at 100 CFU/L sensitivity, delivering results on-site in 25 minutes without laboratory equipment.

Legionella Serogroup 1 Detection — What The ONE Ultra Does

The Hydrosense ONE Ultra Legionella Water Test detects Legionella pneumophila serogroup 1 — the single most dangerous strain of Legionella, responsible for over 90% of Legionnaires’ disease outbreaks worldwide — directly from a water sample collected on-site. Results are delivered in 25 minutes using Lateral Flow Immunochromatographic Assay technology. No laboratory infrastructure or specialist training is required. The World Health Organization provides international guidance on Legionella risk management.

This is the most sensitive Hydrosense ONE product, detecting serogroup 1 at 100 CFU/L from a 250ml water sample. It is the preferred choice for facilities operating in jurisdictions with stringent low-threshold action levels, or where a comprehensive serogroup 1 risk profile is required.

How It Differs From The PRO Ultra

The Hydrosense ONE Ultra detects Legionella pneumophila serogroup 1 only. The PRO Ultra detects serogroups 1–15. For the majority of Legionnaires’ disease risk management programmes, serogroup 1 detection is sufficient — it covers the strain responsible for over 90% of cases. Where full-spectrum detection across all 15 serogroups is required, the PRO Ultra range is recommended.

Sensitivity and Action Levels

• 100 CFU/L — primary detection threshold (250ml sample)
• 1,000 CFU/L — first action level
• 10,000 CFU/L — second action level (Hazard Index)

Result Reading

• C line only: serogroup 1 not detected at test sensitivity
• Lines at 1 and C: serogroup 1 detected at ≥100 CFU/L

VBNC Detection

Detects Viable but Non-Culturable Legionella pneumophila serogroup 1 — bacteria that are alive and infectious but invisible to standard laboratory culture methods. This capability provides a more accurate assessment of real-world risk than culture-based testing alone.

Performance Characteristics

• No interference from other common waterborne bacteria or non-pneumophila Legionella species
• Performs reliably in hard water and high alkalinity conditions
• Robust results across varying environmental conditions

Who Should Use This Test

• Hotels and hospitality venues conducting routine water safety monitoring
• Hospital and healthcare facility water safety teams
• Commercial building managers overseeing cooling towers and large water networks
• Facilities operating scheduled water management programmes requiring the most sensitive serogroup 1 detection available

What Is Included

• 1 × ONE Ultra lateral flow test strip
• 1 × 250ml sample collection beaker
• 1 × 60ml syringe
• 1 × filter
• 1 × 1ml buffer syringe
• Visual step-by-step instructions

Important Note

For environmental water testing only. Not a diagnostic test for human patients. A positive result requires immediate action under your facility’s water management response protocol and consultation with a qualified water safety professional.

Available in Thailand exclusively through BCST — Biochem Scitech Co., Ltd.