Legionella risk assessment in Thailand
A site survey, a schematic of every water system, a risk score for each system and outlet, and a written scheme of control. Carried out to the BS 8580-1 and HSG274 method and written for the checks your auditors, your brand and Thailand's Department of Health actually make.
What is included
- Site survey
- Every tank, pump, heater, loop, cooling tower, spa pool, fountain and little-used outlet, walked with your chief engineer. Where water comes from (municipal, tanker, borehole), where it sits, how fast it turns over.
- Schematics
- Line drawings of the cold, hot and cooling systems, so the next engineer, the auditor and the investigator all see the same picture.
- Measurements
- Temperatures at heaters, returns and the furthest rooms. Free chlorine and pH at the incoming supply, tank outlets and sentinel taps. Cooling-tower condition, drift and dosing.
- Risk register
- Each system and outlet scored for how likely Legionella is to grow and reach people. Scores you can defend, not a colour-coded guess.
- Action plan
- What to fix, in what order, roughly what it costs, and what can wait. Written so an owner can approve it in one reading.
- Written scheme of control
- Control limits, who checks what and how often, what counts as a fail and what happens next. The document tour operators mean when they ask for a "prevention plan".
- Report
- In English, with a Thai summary for your engineering team on request. Mapped on the cover to the framework your property is audited against.
What the report is checked against
We state the framework on the cover and cross-reference every finding to it.
| Framework | Who asks for it | What it expects |
|---|---|---|
| Thai Department of Health guideline; GREEN Health Hotel; 3C Clean Hotel | Provincial health offices, Regional Medical Sciences Centers, Thai-owned hotels | Water management plan, responsible officer, hot water generated above 60 °C and above 50 °C at the tap, free chlorine of at least 0.2 mg/L checked daily, six-monthly sampling, records |
| ABTA guide, European 15-point plan, ECDC accommodation checklist | TUI and other European tour operators and their auditors | Documented prevention plan, trained responsible person, testing records, seasonal clean and disinfection, flushing of unoccupied rooms, spa-pool records |
| ASHRAE 188 water management programme; WHO water safety plan | International hotel brands, hospitals seeking accreditation | Programme team, system inventory and flow diagrams, hazard analysis, control measures, monitoring, verification, documentation |
| BS 8580-1 and HSG274 | UK operators, insurers and claimant solicitors | Competent risk assessment, written scheme, control limits (60 °C stored, 50 °C at outlets, cold below 20 °C), action levels and record keeping |
Sources:Bureau of Environmental Health guideline;TUI Full Operational Assessment;HSE HSG274;Bangkok Biz News, 18 September 2026.
When you need one
- Before a new property opens, or after a refurbishment that touched the plumbing
- When you join a tour-operator programme or a brand asks for a water management plan
- After a positive sample, or a notification that a guest has Legionnaires' disease
- Before high season, after the low-season closure of wings or floors
- Every two years as routine, and after any change of use, ownership or system
What it costs
Priced by property: rooms, number of water systems and cooling towers, and travel from Bangkok. Send the basics through the quote form and we reply with a price and the earliest survey date, usually the same working day.
Common questions
- Is a Legionella risk assessment required by law in Thailand?
- No law requires one as of October 2026. The Department of Health guideline asks hotels for a water management plan, a responsible officer, daily chlorine checks and six-monthly sampling; the GREEN Health Hotel and 3C Clean Hotel programmes are voluntary; tour operators and international brands require assessments through their contracts. On 18 September 2026 the National Communicable Disease Committee approved adding Legionnaires’ disease to the list of diseases under surveillance. That decision concerns the reporting of cases, and it does not by itself create a duty on building owners.
- Do we still need our laboratory tests?
- Yes. Sampling is one of the checks in the scheme, not a replacement for it. We specify where, how often and at which laboratory: TEST TECH (ISO 11731:2017), IMC Thai (AS 3896:2017) or a Department of Medical Sciences Regional Medical Sciences Center (CDC-based method). We recommend the samples are taken by someone independent of the contractor who treats the water, which is what Thai investigators now advise.
- Can you work with our existing water-treatment contractor?
- Yes. The contractor keeps dosing and cleaning; the assessment sets the limits they work to and checks the results independently.
- How long does it take?
- Time on site depends on the size of the property, and the quote says how long it will be. The report follows within five working days of the survey.
- Which areas do you cover?
- All of Thailand from Bangkok, including Phuket, Khao Lak, Krabi, Koh Samui, Pattaya, Hua Hin and Chiang Mai. Vietnam, Malaysia, Singapore, Indonesia, Cambodia, Laos and the Philippines on request, with travel quoted.
Had a positive result, or a notification about a guest?
What you do and record in the first 24 hours is what investigators and tour operators will read later. Get in touch now for advice on disinfection, independent resampling and the evidence they will ask for.