1. ANGUS CONSULTING MANAGEMENT LIMITED
POLICIES AND PROCEDURES Number: 29
POLICY: MINIMIZING THE RISK OF LEGIONELLOSIS
Issued To: A.C.M.L
«Company»
«Address1»
«Address2»
«City», «State» «PostalCode»
Date: January 12, 2006
PRESIDENT’S DIRECTIVE:
It is the direct responsibility of each and every A.C.M.L. Site Project Manager to
ensure that this policy and procedure is adhered to fully. The Site Project
Managers will be held FULLY ACCOUNTABLE for the implementation and
ongoing maintenance of the program. Upon receipt of this policy and Procedure the
A.C.M.L. Project Manager is to immediately ensure their site meets or exceeds the
requirements listed. Audits by A.C.M.L. head office staff and inspections by
A.C.M.L. Health & Safety Representatives will occur on a regular basis. Any
deficiencies will be reported to your respective site senior management
representative. Non compliance will not be tolerated.
Don Campbell
Each A.C.M.L. managed facility will implement the following measures to ensure
the safe operation of building water systems to control the risk of occurrence of
Legionellosis.
SUBJECT
Legionella – An Overview
Legionellae are bacteria. When legionellae are present in aquatic environments,
the risk of transmission of infection to humans depends on the presence of several
factors: conditions favourable for amplification of the organism; a mechanism of
dissemination (e.g. aerosolization of colonized water); inoculation of the
organism at a site where it is capable of causing infection; bacterial strain-specific
virulence factors; and the susceptibility of the host.
Habitats
Under certain circumstance within manmade water systems, the concentration of
organisms may increase markedly, a process termed “amplification.” Conditions
that are favourable for the amplification of legionellae growth include water
temperatures of 25-42 C (77-108F) stagnation, scale and sediment, biofilms and
the presence of amoebae. There is an indication that growth of Legionella is
influenced by certain materials. Natural rubbers, wood and some plastics have
been shown to support the amplification of Legionella, while other materials such
as copper inhibit their growth.

2. Transmission of Legionnaire’s Disease
Data suggests that in most instances transmission to humans occurs when water
containing the organism is aerosolized in respirable droplets (1-5 micrometer in
diameter) and inhaled by a susceptible host. Survival in nature is generally outside
the scope of building engineering and management practices. Amplification,
dissemination and transmission can be influenced by engineering design and
maintenance practices. Subsequent events are influenced by the individual’s
health.
The most effective control for most diseases, including Legionellosis, is
prevention of transmission at as many points as possible in the disease’s chain of
transmissions.
A variety of aerosol-producing devices have been associated with outbreaks of
Legionnaire’s disease, including cooling towers, evaporative condensers,
showers, whirlpool spas, humidifiers, decorative fountains and a grocery store
produce mister. Aspiration of colonized drinking water into the lungs has been
suggested as the mode of transmission in some cases of hospital-acquired
Legionnaire’s disease.
Numerous investigations have demonstrated that cooling towers and evaporative
condensers have served as the sources of Legionella-contaminated aerosols
causing outbreaks of community- and hospital-acquired infection. Outbreak-
associated transmission via cooling towers and evaporative condensers has been
most commonly documented when those infected have been in close proximity to
the contaminated devices.
Showerheads and tap faucets can produce aerosols containing legionellae in
droplets of respirable size. Epidemiologic studies and air sampling conducted
during outbreak investigations have established the role of aerosols produced by
showers and tap faucets in disease transmission. The aeration of spa pools can
result in formation of potentially contaminated aerosols. A range of pathogenic
micro-organisms, including Pseudomonas aeruginosa and L. pneumophila, have
been found in spa pools.
Associated Risks
Most healthy people have a resistance to Legionnaires’ disease. However, some
people naturally have a lower resistance to the disease and would be at high risk
for infection. The following factors result in greater risk for contracting
Legionnaires’ disease.
• Age ( Very young and those middle aged and older are most susceptible)
• Gender (males are twice as likely to contract the disease)
• Heavy Smokers and Drinkers
• Individuals with weakened immune systems
• Individuals with chronic medical problems
Symptoms
Although Legionnaires disease can be fatal, it can be successfully treated with
antibiotics. Early symptoms of the illness resemble that of influenza at the onset,

3. during the first two days of illness. These include slight fever, headache, joint
soreness, muscle cramps, lack of energy, feeling lethargic, loss of appetite, and
diarrhea. As the disease progresses symptoms of pneumonia become more
prevalent such as high fever, a cough that starts out dry and later produces
phlegm, breathing difficulty or shortness of breath, chills and chest pains.
Legionnaires’ disease (LD) cannot be transmitted from person to person through
physical contact. LD is not contagious. If numerous individuals contract LD it is
due to contact with the contaminated water aerosol, not with each other.
Legionella are widespread organisms which can be found in natural and man-made water
systems such as cooling towers and humidifier sumps. There is presently no treatment
program that can completely or permanently eliminate this organism.
POLICY
A.C.M.L. staff must follow ASHRAE guidelines and the recommendations of the water
treatment providers that we work with in order to minimize microbial growth, as well as
the scaling, corrosion and sediment deposition which can harbor the bacteria. This
proactive approach to minimize colonization of Legionella in a water system includes the
following measures:
• Each site that has cooling towers, humidifiers and decorative fountains will
utilize the services of a qualified water treatment specialist to define and
oversee the water treatment program.
o The water treatment specialist will provide each site with a written
water treatment program that includes all test procedures.
o The water treatment specialist, at a frequency not to exceed monthly,
will check on-site that the water treatment program is being carried out
as defined.
o The water treatment specialist will train all new site
maintenance/operating staff to ensure new site employees fully
understand the water treatment program.
• A maintenance service program to regularly drain, clean and disinfect the
system.
o Have in place scheduled maintenance tasks to drain and clean cooling
tower and humidifier sumps, at a minimum frequency of 6 months.
• The addition of corrosion and scale inhibitors to minimize deposition.
o Have in place a scheduled maintenance task to analyze and replace the
corrosion & scale coupons at a minimum frequency of 3 months.
• Regular visual inspections.
o Visual check cooling tower and humidifier sumps, at a minimum
weekly basis for the growth of algae, slime or the build up of deposits.
• A water treatment program that includes the use of alternate biocides that have
a proven ability to effectively control the growth of Legionella.
o Discuss with the water treatment specialist the effective use of
biocides.

4. • Keeping detailed records of water treatment and maintenance programs.
o Each site will maintain detailed daily water treatment records for
cooling towers.
• Monitoring of bleed off and make up rates.
o On a daily basis each site will check & record bleed off and make up
rates.
• At a minimum, quarterly monitoring and recording of general bacteria levels.
o Bacteria levels will be verified by the use of cultural slides and the
results recorded. The bacteria levels should be checked prior to adding
biocide and 8 hours after adding the biocide; this will indicate if the
biocide added was effective.
Each Project Manager is to provide confirmation that the above measures are
implemented at their facility utilizing the form in Appendix A. This form is to be
submitted to your respective site senior management representative on May 1 st and
November 1st of each and every year. You are to create a Preventive Maintenance card
on your Maintenance Management system to serve as a reminder to complete this task.
Regular testing for Legionella has not been mandated by any government agency and is
not recommended on a routine basis because of the difficulty of interpreting test results.
In addition, accurate Legionella testing requires a 10 to 14 day turnaround time. This is
too long a period to allow Legionella monitoring to serve as a useful control tool. There
is presently no official test standard; however a Legionella count of greater than 1000
CFU (Colony Forming Units) has been debated as the level where the potential for
Legionnaires’ disease is more likely to occur.
The A.C.M.L. site senior management representative will discuss chemical water
treatment issues that arise from time-to-time with the A.C.M.L. Site Manager.
For further information regarding Legionella, please refer to the attached documents from
ASHRAE, The Cooling Technology Institute, and Ashland Chemical.

5. ANGUS CONSULTING MANAGEMENT LIMITED
1129 Leslie Street, Toronto, Ontario, M3C 2J6, Tel: (416) 443-8300, Fax: (416) 443-8323
JOB SITE
PROJECT MANAGER
DATE
PROGRAM IN PLACE AT
PROGRAM TO BE
POLICY DIRECTIVE SITE
IMPLEMENTED BY
YES NO
1. Water Treatment Program with Qualified Water
Treatment Specialist for all Cooling Towers,
Humidifier Sumps, Decorative Fountains.
2. Maintenance service program to regularly drain,
clean, and disinfect cooling tower sumps, humidifier
sumps and decorative fountains etc.
3. Water treatment program incorporates the use of
corrosion and scale inhibitors.
4. Conduct regular (weekly) inspections of cooling
tower sumps, humidifier sumps and decorative
fountains, etc.
5. Biocides are alternated in Cooling Towers,
applicable humidifiers, decorative fountains, etc.
6. Detailed water treatment records are maintained on
site.
7. Bleed off and make up meter readings are recorded
daily.
8. At a minimum quarterly monitoring and recording of
general bacteria levels utilizing cultural dip slides in
cooling tower sumps, applicable humidifier sumps,
decorative fountains etc.
Project Manager’s Signature: ____________________________________________ Date: __________________________
APPENDIX A