WHAT YOU NEED TO KNOW ABOUT LEGIONELLA AND ASHRAE’S NEW STANDARD 188.

What is Legionella?Legionella is a naturally occurring bacteria that can be found in water supplies and can cause Legionnaires disease and Pontiac fever, both of which are often referred to as Legionellosis.

Legionellosis SymptomsLegionellosis is a form of pneumonia and comes with all of the various symptoms you would expect:

Female (4,743)

Male (8,809)

<50 Years Old (3,388)

50+ Years Old (10,164)

Annual Legionellosis Cases in US, Australia, & Europe (~13,552)

Patient Age Patient Gender

75%

25%

65%

35%

Legionella & ASHRAE 188

1 Based on WHO fact sheet No 285

ASHRAE standard 188 was approved and adopted in June 2015 and sets out guidelines for the prevention of Legionella in any facility with a centralized water system.

Simply put, the new standard establishes a comprehensive and annually updated management plan as a best practice and industry standard for protecting against Legionella in your water system.

With the adoption of this standard, it is likely that we will see cities and states incorporate this language in their building codes. In addition, many experts believe that the standard will be held as a legal imperative in cases of legionellosis outbreaks, possibly increasing liabilities for facilities that do not have a risk management plan in place.

• Fever;

• Chills;

• Cough;

• Headache;

• Tiredness; and

• Loss of appetite.

Legionellosis is very treatable when diagnosed early, although mortality rates are commonly around 5-10%, if treatment is delayed they sky rocket to nearly 50%.

Contracting LegionellosisLegionellosis exposure occurs through the micro-aspiration of Legionella bacteria in drinking water and ice, and through the inhalation of bacteria in water spray or mists.

Common sources for contracting the disease include ice machines, hot tubs, showers, decorative fountains, and other amenities that produce water spray, mist, or vapor.

Most people exposed to the bacteria do not become ill. Those most at risk for contracting the disease include the elderly, small children, and individuals with suppressed immune systems.

Legionella PropagationLegionella bacteria is found

naturally in our water and will

typically be found in small

quantities at the water source.

Large plumbing systems are often

a perfect breeding ground allowing

these bacteria to multiply and

become a problem.

The bacteria thrives in temperatures

from 68 to 122 degrees Fahrenheit,

but can be present in anything

under 158 degrees.

Most often, facilities find the

highest concentrations of Legionella

where there is stagnation in their

water systems. This might include

cooling towers, tanks, lesser used

plumbing lines, and piping runs

that terminate in dead ends.

Abandoned piping that is capped

but not disconnected from the

system after a remodel can often be

a culprit.

158° F +

Legionella dies instantly

140°-158° F

90% die in 2 minutes

122°-140° F

90% die in 80-124 minutes

108°-122° FSurvives but does not multiply.

68°-108° F

Legionella’s ideal growth range.

Below 68° F

Legionella survives but is

dormant (even at below freezing

temperatures).

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Assessing Your RiskDoes your facility have a centralized domestic water system, cooling tower, or water features? If you answered yes, then ASHRAE’s new standard 188 applies to you.

ASHRAE 188 requires a Hazard Analysis and Critical Control Point (HACCP) risk managment plan. The following is a brief guide, walking you through what it takes to perform an HACCP.

PUT TOGETHER A TEAM

Your team should include:

• the owner;

• your infection control staff;

• the facility manager;

• a domestic water system design professional; and

• an industrial hygienist (optional).

DIAGRAM YOUR WATER SYSTEM

Many facilities do not have a simplifi ed water diagram of their water system.

Diagrams can be a vital tool in assessing risks and determining required controls.

CONDUCT A HAZARD ANALYSIS

Hazards include unique piping arrangements, water fountains, cooling towers and storage tanks.

They also include any locations that are frequented by at risk occupants and staff. DETERMINE CRITICAL

CONTROL POINTS

Control points are those points within your water system where you can measure potential problems or introduce solutions.

Control points can include the incoming water source, water heaters, storage tanks, or distal outlets at the extreme ends of your system.

ESTABLISH A MONITORING SYSTEM

The monitoring system may be as simple as measuring or confi rming the domestic hot watemperatures or complex as watesampling and labtesting.

Most importantly, ensure that all of your HACCP Risk

Management Plan team members are working in the

best interest of your facility and its owners. During risk

assessment and management planning, steer clear of

relying on companies who sell either chemical treatment

options or physical treatment/management systems.

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b

IDENTIFY CORRECTIVE ACTIONS

Corrective actions include those that you may need to take immediately, ongoing maintenance plans that effect daily operations, and establishment of protocols for future system revisions.

Corrective actions can include changes in water temperatures, installation of chemical treatment systems, or piping modifi cations to limit growth locations among many others.

CREATE CONFIRMATION PROCEDURES As part of the HACCP, you must be able to confi rm that it is working as expected. This will typically include testing water samples to confi rm chemical and bacteria levels.

DEFINE RECORD KEEPING NEEDS

A number of processes and check points will need to be documented during implementation to show compliance and provide guidance for future decision making.

SCHEDULE AN ANNUAL UPDATE

The annual update confi rms that critical control points are within reasonable parameters, systems are functional and occupant and staff risks are limited.

Regardless of the water source, incoming water will always carry

some low level of the Legionella organism.

As a general rule, keeping the level of Legionella in your water

system at or below the level of your water source should be

suffi cient to protect against your customers, patients, tenants

and/or employees contracting the disease.

Laboratory testing is the only way to be certain whether your

current system has acceptable levels of Legionella bacteria;

however, it isn’t necessarily advisable to test your water without

going through a Legionella risk assessment fi rst.

Detecting Legionella

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Protecting Against LegionellaAs you go through your water system risk assessment, you will likely encounter a number of areas that can be improved to eliminate Legionella growth and decrease the risk of someone contracting the disease.

Domestic Hot Water StorageSome of the most commonly identified improvements are to the system’s hot water tanks. Typically, facilities will store water in these tanks at a low enough temperature to prevent scalding; however, those lower temperatures provide a perfect environment for Legionella growth.

The easiest remedy for this condition is to flush your tanks periodically and store your hot water at 140ºF, mixing it with cold water to deliver lower temperatures at the point of use.

Cooling TowersCooling towers have long been a source of legionella, the recent outbreak in New York City is a prime example of what can happen when they are not maintained correctly.

Preventive measures for ensuring that legionella doesn’t contaminate the system are imperative and include startup procedures, ongoing water treatment, monitoring, and corrective actions plans. Additionally, a contingency response and emergency disinfection plan should be in place in case a suspected correlated legionellosis case(s) arises.

Piping SystemWhen pipes aren’t used, the water stagnates and Legionella is able to colonize and grow. You will find these types of problems where renovations have abandoned sections of piping without disconnecting them from the system, creating a “dead leg”.

Your risk management plan should address remediation of any existing dead legs and provide guidelines for future system modifications to limit the amount of dead-end piping.

Point of Use FiltrationEquipping fixtures with point of use filtration is a proven and effective way to limit risk for at-risk occupants.

Many new systems are on the market that tout

the ability to control Legionella. Most of these systems have

had limited testing and their effectiveness is

unknown.

The solutions presented here are well-tested

and industry standard. When these strategies

are implemented correctly, you can be

sure that they will provide the intended

results.

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Secondary Treatment SystemsA secondary treatment system is a likely recommendation where there are at-risk occupants and there is no reasonable way to limit the system’s dead-end piping. These systems do come with some drawbacks; however, there are cases where secondary treatment is your only, or most affordable option. In those cases you may consider any one of the following systems.

Chemical Chlorine Injection

Chlorine injection has limited kill rates and is the least effective of the secondary treatment systems available and there is a high cost associated with the chemicals. However, these systems do have the ability to provide electronic feedback, clearly demonstrating the chemical concentration levels. Chlorine injection is often used to shock a system if there has been a spike in Legionella.

Chemical Chlorine Dioxide Injection

Chlorine dioxide systems have the same electronic feedback capabilities as chlorine injection systems with the added benefit of being less corrosive and more effective in managing legionella. Chlorine dioxide is costly and the chemical is toxic so safe handling and managing concentration levels in your water system is imperative.

Copper Silver Ion System

Copper Silver Ion systems disperse positively charged ions into the water system and over time the ions destroy the biofilm that harbors Legionella. These systems are highly effective and have a lower maintenance cost than chemical systems, but they do require regular lab testing to measure the level of ions in your system and regular cleaning of the nodes to ensure proper function.

There is no standardized “right solution” for every facility.

Your unique needs, operations, and systems will require tailored recommendations to provide the best value and a management plan that is actionable and easy to maintain.

Notkin or other specialized design professionals can help to organize and guide your facility assessment team.

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If you have questions about ASHRAE Standard 188 or would like more information about your options for controlling the

risk of Legionella at your facility, give us a call.

(206) 448-1911

www.notkin.com