Assured water treatment for hotels

Supplying clean, wholesome water is mandatory for the UK hotel and hospitality sector. Here’s a quick guide to ensuring guests and staff stay healthy.

The UK’s hotel and hospitality venues have just experienced their most challenging two years ever. Whether it’s wearing face shields or disinfecting surfaces, safeguarding guests and staff is top of the agenda.

Don’t forget to give water quality the same priority. Many facilities are only now re-opening after extended closures and that makes them the perfect target for waterborne pathogens like viruses and bacteria.

Meet your new residents: bacteria and viruses

Water is used everywhere in hospitality, from food production, drinking and showering to cleaning, laundry and air conditioning. Many hotels have swimming pools and hot tubs too. As mains water moves through their distribution system and is stored locally, its chlorine levels drop and contamination becomes possible.

Most microbes are harmless but still form biofilms within pipework and appliances. Along with sediment, scale and corrosion, these biofilms are perfect host environments for pathogens, of which Legionella is the most potentially deadly.

Though harmless at low concentrations, Legionella infections can be serious, even fatal. There’s no vaccine; prevention is the only safeguard.


Legionella grows in stagnant water

Hotel owners may not realise how exposed they are to a Legionella outbreak. Regardless of Covid, many hotels close in winter or experience long periods of low occupancy. Some rooms can go unused for weeks. Water turnover drops dramatically and – because legionella and other pathogens love stagnant water – so does water quality.

Even with full occupation, hotels’ recirculating hot water systems are vulnerable. There are often areas where water moves slowly or stops altogether – “dead legs” or dead ends – and temperatures drop to 20-40°C: perfect conditions for biofilm formation and Legionella growth.

Maintaining the 60°C needed to kill Legionella raises the risk of scalding guests, so thermostatic mixer valves are often fitted. But the mixed water’s lower temperature then leaves downstream outlets like shower heads at risk. Low flow fittings are similarly unprotected.

Water safety is your legal duty

Under the 1974 Health and Safety at Work Act, it’s the hotel owner’s legal duty to assess water contamination risk, create a control strategy and ensure it is carried out. The HSE’s ACOP L8 regulations offer practical guidance on how to do this. Though not mandatory, regular water quality testing is the best way to detect high levels of Legionella.

Preventative actions include flushing taps, showers and other fittings in low occupancy rooms at least weekly, letting hot water reach its maximum temperature, and cleaning and de-scaling shower heads and hoses at least quarterly. Clean tap aerators and any other filters too.

Other water-using devices like ice machines may require additional attention. Flushing and cleaning the full system annually is also wise. Consider draining the hot and cold water tanks and circuits in advance of a shutdown and, before reopening, draw up and execute a recommissioning plan for the entire water system.

What if Legionella takes hold?

If Legionella or other pathogens are detected, first, carefully assess the existing system. Can its design be changed to remove areas of no or low flow and improve circulation?

Is the hot water sufficiently hot? Are pipes and tanks adequately insulated? Test temperatures at “sentinel” outlets closest to and furthest away from the hot water supply.

Thoroughly flush the system and treat with a biocide, then run further water testing. If Legionella still persists, a secondary disinfection system is most likely needed.

Choose chlorination for peace of mind

After long shutdowns, chlorination with chlorine dioxide (ClO2) is proven to remove biofilms and stamp out Legionella in hotel water systems. Even better, ongoing dosing with this potent biocide provides continuous disinfection – and peace of mind.

Compared to pure chlorine, ClO2-treated water is more palatable for guests. A single system can protect all hot and cold water, right from the tank through to all outlets.

With effective secondary disinfection in place, hotels don’t need to worry if hot water circuit temperatures drop below the recommended 60°C. This can save on costs too. Lowering the average temperature of energy-hungry hot water circuits by just a few degrees cuts heating bills significantly.


State-of-the-art secondary disinfection

Effective chlorination eradicates legionella and biofilms – and makes sure they don’t return. Gaffey’s compact ChloriDOS® iOX® chlorine dioxide blending systems suit space-constrained hotels perfectly and can be retrofitted to almost any water system in a single day. With WRAS-compliance, they consume low hazard chemicals and can be monitored online.

Conventional dosing systems can start to malfunction soon after installation and, if servicing is ignored, the water’s residual biocide levels drop and Legionella returns all too quickly. ChloriDOS® iOX®’s patented vacuum auto-mixing is adjustment-free, adding consistent amounts of biocide over years of operation. The system is ultra-reliable, requires minimum servicing and is safe and easy for untrained staff to operate. Its accurate dosing also minimises chemical consumption and operating costs.

Gaffey has installed numerous hotel systems and will advise on the correct equipment to suit each building and its water consumption. With ChloriDOS® iOX® , you can be confident that your hotel’s water system is safe – and will stay that way.

Don’t worry about your hotel’s water quality. ChloriDOS® iOX®  safeguards your guests and staff, 24/7.

Call our team today on 01254 350180


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