CEC Consultants' Recommendations for Legionella Prevention; Cleveland Auto Plant Closes; Legionella in Cooling Towers Suspected
CLEVELAND--March 15, 2001--Legionella outbreaks and its incidence are somewhat common. Legionella bacteria has always been around. Hopefully increasing the public's awareness will now minimize the chances of this bacteria continuing to plague us all. Legionella is almost everywhere in water and soils. The good news is that it's ability to thrive, multiply, be aerosolized (made into droplets), and disseminated can be controlled.Those who work with or near equipment that is traditionally high-risk equipment need to be especially aware of proper maintenance and controls to minimize the chance of contamination. Equipment that has a special capability to breed, multiply, and or disseminate legionella includes the following.
1. Architectural Fountains and Waterfalls: (Malls, shopping
centers, restaurants, and even private residential and
office displays).
2. Cooling Towers: (These come in many types and sizes but in
general they are at or near wherever commercial air
conditioning or refrigeration processes take place. This
could mean hospitals, schools, and or facilities even with
large air compressors or cold storage facilities).
3. Evaporative Coolers: (Athletes at football and or baseball
games may be at risk as are those at some industrial
facilities that have added evaporative cooling in lieu of
air conditioning).
4. Evaporative Air Coolers: (These are another cooling tower
technology that are also associated with commercial are
conditioning and heat rejection processes).
5. Air Washers/Scrubbers: (These are associated with
processes where particulate and or chemicals are scrubbed
from the air using water mist/sprays. In some cases the
processes remove acid fumes and odors).
6. Car Washes: (Car washes with recirculated water could be a
source in summer periods, especially rinse sections).
7. Showers: (People showering and/or cleaning/maintenance
personnel who are stationed near or frequently in contact
with showers that have domestic water systems loaded with
Legionella can be at risk)
8. Humidifiers: (Humidification systems including even
residential units could be at risk, many commercial
buildings, art museums, printing plants, and even document
processing facilities have humidification systems).
9. Parts Washers: (Parts cleaning processes in industrial
plants can make for risks. Especially those that have
rinses and or water blow off sections associated with
them).
10. Paint Booths: (Many paint booths and painting processes
use humidification systems to control and maintain optimal
humidity)
In every case this equipment faces common characteristics that make it capable of accelerating the breeding rate, making it into aerosol, or spreading the droplets. Remember, it's very unlikely that one would ever get Legionella from drinking contaminated water or skin contact. It's primarily an issue of breathing in droplets.
What Can Be Done?
1. Personnel Protective Equipment
Make sure that your staff servicing any cooling towers or
at risk equipment wears proper personal protective
equipment including at least dust masks or respirators to
minimize the chance for the inhalation of droplets.
2. Medical Considerations
Consider prioritizing who works on which assignments.
Remember, those that smoke and or have some type of immune
system compromise are especially at risk. Consider other
issues like people who may have chronic allergies and/or
cancer patients. Those under some type of medical care, and
even those just getting over a cold or flu should not be in
a position to be exposed.
3. Start-up/Shut Down Procedures
Make sure that you have proper start-up/shut down
procedures that parallel ASHRAE guidelines. ASHRAE is the
American Society of Heating Refrigeration and Air
Conditioning Engineers. These procedures discuss topics
such as proper draining, decontamination, and maintenance
procedures for minimizing risks.
Longer Term Treatment Considerations
It will only be through longer-term monitoring and enhanced maintenance practices that this threat will be minimized. This means that proper chemical treatments including chlorination or ion technologies will need to be implemented. Ion technologies allow for a simple less cumbersome and less corrosive approach in some cases than chemicals. Ion treatments involve a small device with copper and/or silver anodes that put small amounts of silver and or copper into the water. These metals are toxic to most of the Legionella bacteria under the right concentrations.
There are also design considerations that should be considered. An example of some of the more difficult and costly issues that many sites need to address are as follows:
Domestic Hot Water Systems
The energy conservation craze and high gas prices of late have made for some to consider turning down water temperatures. In some cases this can lead to making the right conditions for the bacteria to proliferate through piping systems. Nursing homes, hospitals, and other types of facilities where it may be common for people to be susceptible, need to store and maintain water at over 140 degrees Fahrenheit. This means systems have to be redesigned to include cold water mixing valves near shower and or sink areas to avoid scalding. This is a significant and often expensive design change.
Cooling Tower Locations
In many cases cooling towers have never been located with minimizing the potential for Legionella as a design criteria. In many cases buildings have these perfect Legionella distributors located near outside air intakes or public areas. The location of cooling towers with respect to air intakes and regular exposure to personnel of the airborne mists should be reviewed. In some cases this may mean moving cooling towers, moving air intakes, and or replacing towers with air cooled equipment. All of these options are expensive and very cumbersome to implement.
If you suspect a problem or need help!
Emergency precautions should include immediate shut down of systems, testing, and decontamination. Our firm can help by reviewing your systems, sampling, creating start-up/shut-down procedures, and/or reviewing longer term fixes required.
John Puskar, P.E.
Principal
CEC Consultants, Inc.
John Puskar, P.E.
Biography:
Mr. Puskar, P.E. serves as Principal of CEC Consultants, Inc. based in Cleveland, Ohio. Mr. Puskar started the firm in 1984 after serving as a Senior Energy Systems Engineer at Standard Oil of Ohio's Cleveland corporate headquarters. CEC has been retained for numerous indoor air quality investigation and remediation issues including discovering health issues at the City of Parma Municipal Court facility. Mr. Puskar is a licensed professional engineer in the state of Ohio and several other states. Mr. Puskar holds a bachelors degree in Mechanical Engineering from Youngstown State University and a Masters Degree in Business from the Weatherhead School of Management at Case Western Reserve University. Mr. Puskar has received numerous professional awards including being named the "Young Engineer of the Year", by the Cleveland Engineering Society, One of the Crain's Cleveland Business 40 under 40, and receiving the Technical Service Award from the Cleveland Technical Societies Council. Mr. Puskar has served as chairman of the local American Society of Mechanical Engineers, Association of Facilities Engineers, and the Cleveland Technical Societies Council. Mr. Puskar has also been published in numerous national professional and trade journals and has delivered papers at more than a dozen professional conferences.
CEC Consultants Inc.
CEC Consultants Inc., Cleveland, Ohio specializes in developing corporate-wide indoor air quality, energy, ventilation, combustion, and overall safety programs for Fortune 100 corporations. Over the last 17 years CEC has completed hundreds of hands-on engineering studies and troubleshooting projects worldwide. Major clients such as Ford Motor Company Worldwide, General Motors, BP America, Johnson & Johnson and many others seek CEC out.
You can reach us at 216/749-2992 - John R. Puskar, P.E.
www.cec-consultants.com
www.combustionsafety.com