Presented by:Helen CerraCh T t IChemTreat, Inc.October 11, 2012

• ASHRAE Standard 188P

• Status/ review

• CTI Update

St t / i• Status/review 

• Bacteria Control

Quebec City, Quebec

Edinburgh, Scotland

Chicago, Illinois

Blanes, Spain

• Standard 188 – Prevention of Legionellosis Associated with Building Water Systems g y

• Draft Standard has had two public reviews• Draft Standard has had two public reviews• Expect publication 2013

Purpose ‐ Present practices for the prevention of l i ll i i t d ith b ildi tlegionellosis associated with building water systems.

Based on Hazard Analysis Critical Control Point (HACCP)Risk Management for US Armed Forces  gNASAFood industry to control infectious organism transfer

Provides methods of risk management for ti l i ll i ith t li dpreventing legionellosis with centralized 

industrial and commercial building water systemssystems Human occupied buildings.T b d b th i l d i To be used by those involved in ownership/design/construction/installation/ mananagement/operation/maintenance andmananagement/operation/maintenance and servicing  

• Build the team

• Survey• Survey

a) Multiple housing units with one/more central water heaters.

b) Building more than 10 stories tall (includes ) g (below grade).

c) Inpatient healthcare facility.c) Inpatient healthcare facility.

d) Occupants ages >65 or receiving chemo for cancer or bone marrow transplantcancer or bone marrow transplant.

e) One or more whirlpools and/or spas.

f) One or more aerosol‐releasing water features or devices (ornamental fountains, misters (atomizers), air washers or humidifiers) within it or located on premises.

g) Incoming potable water – total residual g g phalogen = <0.5 mg/l as Cl2. 

• Does the building have one or more cooling towers and/or evaporative condensers that provides cooling and/or refrigeration for the HVAC&R systems?  

Process for Determining ASHRAE Std. 188 Compliance

Form Team

Survey F ilit

Document survey 

Team Facility findings

Are there risk 

factors?

Repeat survey  each year

Develop HACCP  Plan

NoYes

Hazard Analysis Critical Control Point

A PROCESSA PROCESS 

1 Conduct hazard analysis1. Conduct hazard analysis2. Determine critical control points (CCP)3 Establish critical limits for each CCP3. Establish critical limits for each CCP4. System to monitor control of CCP5. Corrective action if CCP not under control6. Verify HACCP is working effectively7. Documentation of procedures and record

• Select a Team

• Process Flow Diagram

• Perform Hazard Analysis identify hazard• Perform Hazard Analysis –identify hazard

• Validation Criteria – quantitative control

• Establish Validation Summary

• Establish Verification Schedule 

• Select a Team

• Person with an understanding of HACCP

• Owner/President/AdministratorOwner/President/Administrator

• Facilities Chief/Manager

EHS• EHS

• Hospital – Infection Control Officer

• Risk Management

• Identify end point uses of H2O Systems• Potable 

• Utility

• Develop two process flow diagrams

• Illustrate how water is received deliveredIllustrate how water is received, delivered, processed

• Walk the lines!• Walk the lines!

• Identify critical control points  • A point where control can be applied to prevent or eliminate a safety hazard or reduce it to an 

bl l lacceptable level.

• Indicate on the process flow diagrams

• Establish critical control limits for each CCP

• Develop Hazard Analysis Summary Document  

ProcessStep

System Hazard Risk Signifcant

Basis for Risk

Control CCP 

Cooling Coolingtower

Legionella yes Located near walk way

Control MB,Corrosion, deposition. 2x/yr cleaning

yes

y 2x/yr cleaning

• Set up a monitoring procedure 

• Set up frequency of monitoring

• Establish Corrective Actions when CCPEstablish Corrective Actions when CCP deviates from the limit

• Validate CCP limit corrective action• Validate CCP, limit, corrective action • ex. ‐ CTI Guideline for MB 

S i tifi f id• Scientific reference, evidence

• Test for legionella

• Establish verification procedures• Activities, other than monitoring that determines the validity of the analysis and control system and h d h lthe system is operating according to the plan.

• Establish documentation and record keeping procedures 

• Produce a single document of the plan• Flow diagrams• Hazard Summaries• Monitoring schedule• Equipment maintenance procedure q p p• Validation summary• Verification scheduleVerification schedule• Plan for water disruption

• Design, Maintenance , and Operations Controls

• Reference ASHRAE Guideline 12

• Design, Maintenance , and Operations Controls• Section 8.1 – Potable

• Section 8.2 – Cooling towers and Evaporative Condensers

• Section 8.3 – Whirlpool spas

• Section 8.4 – Decorative fountains,…

• Section 8.5 – Aerosol generating air coolers, humidifiers, and air washers

• Referencee e e ce• ASHRAE Guideline 12• ASHRAE “Handbook of Fundamentals” Chapter 49, Service Water  Heating

• Construction/renovation• Startup/Shutdown• Maintenance/ Monitoring temp and Cl• Emergency Disinfections

• Hot/Cold water systems  

• Equipment Siting/Start‐up plan ‐new

• Written system maintenance plan

• Written water treatment plan for control ofWritten water treatment plan for control of microbiological activity, scale, and corrosion.• Solids evaluationSolids evaluation

• Shutdown and start‐up plan

Di i f i d (2)• Disinfection procedures (2)• Remedial on‐line and emergency

• Reference ASHRAE Guideline 12

• ASHRAE Handbook – applications chapter onASHRAE Handbook  applications chapter on Water Treatment

• Cooling Technology Institute• Cooling Technology Institute

• Association of Water technologies (AWT) 

• Reference – state and local codes for public swimming pools and spas.

• If none apply, follow voluntary consensus std APSP 11‐ Standard for Water Quality in Public Q yPools and Spas.

• No references

• Siting of equipment• Contamination

• Access to pumps, filters, etc

• External heat sources

• Operation/Maintenance

R f ASHRAE G id li 12• Reference ASHRAE Guideline 12

• Siting ‐ Contamination, Access

• New System Startup

• Maintenance/ Water treatment planMaintenance/ Water treatment plan

• Shutdown and Startup plans

Di i f ti• Disinfection

• Guideline: Best Practice for Control of Legionella

• Working on producing a Standardg p g• Still working ‐ release in 2013?

• Expect testing for Legionellap g g

• Maintain continuous low level residual of free halogen (chlorine or bromine)(chlorine or bromine)

• If continuous halogenation not possible, intermittent use of halogen necessary for minimizing riskBi di b d id i i d• Bio‐dispersant can be used to aid in penetration and effectiveness of biocides

• Periodic addition of non‐oxidizing biocide as required to maintain clean conditions for both continuous and intermittent 

Parameter Dipslides Agar Pour or

Microscopic Examor

PetrifilmExam

Planktonic Counts

<10,000 CFU/ L

<10,000 CFU/ L

No higher lif fCounts

(Bulk Water)CFU/mL CFU/mL life forms

Sessile Counts

<100,000 CF / 2

<100,000 CF / 2

No higher lif fCounts

(Surfaces)CFU/cm2 CFU/cm2 life forms

Deposits NA NA No higher Deposits NA NA No higher life forms

• Ensures human health  

• Lowers maintenance $$Lowers maintenance $$

• Improves heat transfer  

• Reduces corrosion• Reduces corrosion (MIC)

Microorganisms TypesMicroorganisms Types

• Bacteria• Fungi• Algae

Protozoa• Protozoa

Pseudomonas biofilmPseudomonas biofilm

Material T C (W/mK)Carbon steel                   51.92Steel                                 46.86

l l ( )Stainless Steel (316)      16.30Copper                            384.00W t 0 61Water 0.61Biofilm ~ 0.63

Values from Characklis, William and Marshall, Kevin, eds., Biofilms, 1990 John Wiley & Sons, Inc.

Scale T C (W/mK)l bCalcium Carbonate  2.26‐2.93 Sherwood et al., 1975

Calcium Sulfate 2.31 “C l i Ph h t 2 60 “Calcium Phosphate 2.60 “Magnesium Phosphate  2.16 “Magnetic Iron Oxide 2 83 “Magnetic Iron Oxide     2.83Biofilm 0.63 Characklis et al., 1981

Bacteria ControlBacteria Control

• Oxidizing Biocidesidi i i id• Nonoxidizing Biocides

• Biodispersants• Biodispersants

• HALOGENS• HYPOCHLOROUS ACID, i.e. CHLORINE

• HYPOBROMOUS ACID, i.e. BROMINEIODINE

• HYDROGEN PEROXIDE

• CHLORINE DIOXIDECHLORINE DIOXIDE

• OZONE

ChlorineChlorine

• Most widely used biocide• Cl gas or liquid sodium hypochlorite• Cl2 gas or liquid sodium hypochlorite• Less effective at high pH and in the

f ipresence of ammonia• Increased safety and discharge concernsy g

• REQUIRES EDUCTOR FEED SYSTEMFEED SYSTEM

• SAFETY AND HANDLING CONCERNSCONCERNS

• DEPRESSES WATER pH

REGULATORY• REGULATORY REQUIREMENTS

•Available Cl2 -10-12%•Liquid - drums, totes, bulkq , ,•One gallon = 1 pound of

Cl2 (gas)• Sensitive to light/heat•Relatively economical  

80

100

60

80

% HOCl

20

40

07 7.5 8 8.5 9

pH

• SLOWER DISSOLVINGSLOWER DISSOLVING

• 89% FAC

• Smaller SystemsSmaller Systems

• MORE EFFECTIVE AT HIGHER pHs

• LESS VOLATILE

• LESS CORROSIVE TO STAINLESS STEEL

• IMPROVED COPPER CORROSION INHIBITION

• IN AMMONIA CONTAMINATED WATER, BROMAMINES ARE BETTER BIOCIDES THAN CHLORAMINES

• DISCHARGE LIMITATIONS

Bromine• Activated bromide

o eActivated bromide(NaBr + Chlorine source)

• Liquid Stabilized Bromine• Bromochlorodimethylhydantoin

(BCDMH)• Effective at high pH• Effective at high pH• Bromamines effective• Reduced halogen feed and dischargeg g

Advantages DisadvantagesAdvantages• Most cost effective

bromine approach

Disadvantages

• Two product feed  (NaOCl or Cl )pp

• Improved effectiveness at high pH

(NaOCl or Cl2)

• Biocidal in presence of ammoniaC ti f N B• Can vary ratios of NaBr with NaOCl or Cl2

Cl t hit li id• Clear, water-white liquid• Inorganic salt • 38 – 42% NaBr• Supplied in drums, totes, and bulkSupplied in drums, totes, and bulk• Not a biocide unless combined with an

oxidizing agent (Cl NaOCl)oxidizing agent (Cl2, NaOCl)

NaClNaOBrNaBrNaOCl NaClNaOBrNaBrNaOCl

HOBrNaOH

REACT 12.5% BLEACH WITH 40% SODIUM BROMIDEREACT 12.5% BLEACH WITH 40% SODIUM BROMIDE

2 73 GALLONS OF 12 5% BLEACH TO ONE2.73 GALLONS OF 12.5% BLEACH TO ONE GALLON OF SODIUM BROMIDE

• BCDMHBCDMH

• DRY PRODUCT

• BROMINE ANDBROMINE AND CHLORINE DONOR

• 1:1 MOLAR RATIO1:1 MOLAR RATIO

• BROMINATOR

• ONE DRUM, LIQUID • LESS PRONE TOONE DRUM, LIQUID

• 6.8% FAC

• COMPLEXED WITH A

LESS PRONE TO PUMPING PROBLEMS COMPARED TO BLEACHCOMPLEXED WITH A 

STABILIZER, WHICH ALLOWS IT TO BE 

• DOESN’T REQUIRE DILUTION WATER

FORMULATED IN ONE PRODUCT

• LESS VOLATILE

ADVANTAGES DISADVANTAGESADVANTAGES

• ENVIRONMENTALLY FRIENDLY

DISADVANTAGES

• REQUIRES HIGH DOSAGE FOR CONTINUOUS 

• DECOMPOSES TO WATER AND OXYGEN

CONTROL

• SOLUTIONS OF >30% ARE REGULATED BY THE• CAN DISPERSE SLIME 

MASSES

• DOESN’T FORM THMs

REGULATED BY THE DEPARTMENT OF HOMELAND SECURITYDOESN T FORM THMs

• DOESN’T ADD CHLORIDES

• A dissolved gas in water• Unstable so it is normally y

generated on site• Disagreeable odor, sweet &

i i i i il hl iirritating, similar to chlorine• Rapid-acting bactericide• Good oxidizer oxidizes cell walls• Good oxidizer - oxidizes cell walls

and membranes

• Rapid kill rate at low ppmRapid kill rate at low ppm• Broad‐range bacteria, fungi, & virus destruction • Penetrates & sluffs biofilm, killing resident organisms  

D t f t ih l th (THM )• Does not form trihalomethanes (THMs)• Does not react with ammonia or chlorinated organics• Does not form hypochlorous acid or free chlorine • Less corrosive than chlorine • Remains effective across broad pH range• Threshold odor is ~ 0 1 ppmThreshold odor is   0.1 ppm

• Sodium chlorite• Chlorite + acid + bleach• Chlorite + Hydrochloric acid• Chlorite + Cl2 gasC o te C 2 gas• Chlorite + ion exchange/catalyst• Chlorite + Electrochemical• ICA Trinova Sachets• ICA Trinova‐Sachets• Stabilized chlorine dioxide (CL3000) 

4 50

5.00

3.50

4.00

4.502)

2.00

2.50

3.00

ppm

(as

Cl2

Stabilized Hypobromous AcidHypobromous

Acid

0.50

1.00

1.50

p

Hypochlorous Acid

0.00

0.50

0 10 20 30 40

TIME (MINUTES)

Acid

CHLORINE IS TWICE AS VOLATILE AS BROMINE

Nonoxidizing Biocides

hi li

Nonoxidizing Biocides

• Isothiazolin• Glutaraldehyde• Dibromonitrilopropionamide

- (DBNPA)• Carbamate• Quaternary AminesQ y• Terbuthylazine

• Bacteria – fungi, show activity to algae

• Slower acting • not good for short residence timesg

• pH < 9

• Deactivate with bisulfite• Deactivate with bisulfite

• Skin sensitizer

• Broad Spectrum ‐Bacteria, fungi, yeast• Sulfate Reducing Bacteria

• Compatible with Oxidizersp

• Not compatible with ammonia

• pH range 7 10• pH range 7‐10

• Faster acting at higher pH

• Deactivate with bisulfite

• Broad Spectrum

• Fast kill

• Compatible with most system treatmentsCompatible with most system treatments

• Hydrolyzes to less toxic by‐products

H 4 8• pH range 4‐8

• Increasing T at a pH will speed half‐life

• Broad Spectrum

• Antifungal activity – paper mills

• Stable up to pH of 12Stable up to pH of 12

• Decompose at acidic pH

N t tibl ith idi i t• Not compatible with oxidizing agents 

• Surface active properties• Clean surfaces

• Used for zebra mussel control

• Low in cost

• Used in combination with other biocides• Used in combination with other biocides

• Foaming issues

• Primarily ‐ algaecide

• Compatibility with oxidizers• Control bacteria and algae in summer monthsg

• Interferes with photosynthesis of plants 

• Effective at cooling system pH• Effective at cooling system pH

Biocide SelectionBiocide Selection

• Microorganisms• pH• Holding Timeg• Scale/Corrosion Program• System Contaminants• System Contaminants