HTM 2030 Water Regulations

HTM WATER REGULATIONS

Healthcare Technical Memorandum (HTM) 

The healthcare technical memorandum (HTM) provides guidance on disinfection processes. Specifically it refers to the validation of all types of ultrasonic cleaner and washer disinfector used in the healthcare sector. HTM provides guidance on contamination within steam supply, and also defines the specifications for ‘clean steam’ used within the healthcare sector.

HTM defines microbiological specifications that washer disinfectors must meet to ensure patient safety. The final rinse water after the disinfection stage has occurred, must meet quality standards to minimize microbial contamination of disinfected products.

It is recommended that this monitoring be performed on a weekly basis.

Specification for Endoscopy

Taken from Health Technical Memorandum 01-06:Decontamination of flexible endoscopes: Part B: Section 2.2

Application Requirement

Initial flush:- Hardness less than 200 mg/L CaCO3

Intermediate flush:- Hardness less than 200 mg/L CaCO3

Water for diluting disinfectants and detergents:- Hardness less than 50 mg/L CaCO3

Final rinse-water(see also Table 1 in HTM01-06 Part E – ‘Testing methods’)
Hardness less than 50 mg/L CaCO3
TOC less than 1 mg/L
Conductivity less than 40 µS/cm, unless disinfectant added

Note: If any of the above parameters for the final rinse-water are above the stated limits, additional water analysis will be required to determine the source of the problem (for example, pH, chloride, heavy metals etc).

The criteria and parameter limitations for other contaminants including salts not listed in this Table should accord with the rolling revision of the WHO guidelines for drinking water quality.

In light of the use of variable supply quality through the recently established national water grid, it is appropriate for providers to periodically discuss this issue with their water supplier.

Tests for hardness and electrical conductivity are detailed in HTM 01-06 Part E – ‘Testing methods’.

Taken from Health Technical Memorandum 01-06:Decontamination of flexible endoscopes: Part E: Section 6.3

Water test Satisfactory results Frequency
Total organic carbon Less than 1 mg/l Yearly
Appearance) Clear,bright and colourless Yearly
pH 5.5 to 8.0 Yearly
Electrical Conductivity Less than 40 µS/cm at 25°C Weekly
Hardness Less than 50 mg/l CaCO3 Weekly (if appropriate)
Total viable count (TVC) Less than 10 cfu/100ml acceptable Weekly
Enviromental mycobacteria Non-detected in 100 ml samples Quarterly
Pseudomonas aeruginosa Non-detected in 100 ml samples Quarterly

Specification for Sterile Services

Taken from Health Technical Memorandum 01-01: Management and decontamination of surgical instruments: Part D: Section 3.24

Application Requirement

Cold water:- Flushing

Potable water:- Flushing/washing

Soft potable water (<50mg/L / CaCO3):- Cleaning with detergent or enzymatic cleaners

Softened water-based exchange softener:- Desirable in all water >50mg/L/ CaCO3  Essential in all water >125mg/L / CaCO3 for use in WDs

Deionised water:-  Final rinse water in all WDs Thermal disinfection in all WDs

Reverse osmosis:-  Final rinse water in all WDs Thermal disinfection in all WDs

Note:- This table shows suitable applications for the various qualities of water commonly available.

Although water of lower quality may be used, this will normally require additional chemical additives and might entail some impairment of the WD performance. The terms “softened”, “deionised” and “reverse  osmosis” refer to defined purification processes.

Taken from Health Technical Memorandum 01-01: Management and decontamination of surgical instruments: Part D: Section 3.4

Determinant and unit Maximum permitted values
Final rinse Other stages
Appearance Clear, colourless
Degree of acidity(pH) 5.5 to 8.0
Conductivity at 25°C (µS/cm) 30
Total dissolved solids (mg/100ml) 4
Total hardness CaCO3 (mg/100ml) 50 210
Chloride, Cl(mg/l) 10 120
Heavy Metals, determined as Lead, Pb(mg/l) 10
Iron, Fe (mg/l) 2
Phosphate, P2O5 (mg/l) 0.2
Sillicate, SiO2 (mg/l) 0.2 2
Total viable count (TVC) at 22°C (cfu/100ml) 100
Total viable count (TVC) at 37°C (cfu/100ml) 100
Bacterial endotoxins (EU/ml) 0.25