OSHA TECHNICAL MANUALSection III: Chapter 7LEGIONNAIRES’ DISEASETable of Contents:I.II.III.IV.V.VI.IntroductionDisease RecognitionSource IdentificationInvestigation ProtocolControlsBibliographyList of Appendices Appendix III:7-1. Employee Awareness ProgramAppendix III:7-2. Physical Survey and Water Sampling ProtocolAppendix III:7-3. Water Sampling GuidelinesAppendix III:7-4. Legionnaires' Disease Case IdentificationAppendix III:7-5. Water Treatment Protocols for Facilities That Have Experienced aLegionnaires' OutbreakThe mention of trade names, commercial products, or organizations does not imply endorsementby OSHA or the U.S. Government.I. IntroductionThis chapter provides information to assist industrial hygienists in the assessment of work sitesfor potential Legionnaires' disease. It provides information on disease recognition, investigationprocedures to identify probable water sources, and control strategies. The primary focus of thisdocument is on the control and prevention of contaminated water sources, not on caseidentification, an area of expertise primarily exercised by local health departments frequently inconjunction with the Centers for Disease Control and Prevention (CDC) in Atlanta. Appendicesinclude details on conducting an employee awareness program, water sampling protocols andguidelines for acceptable levels of the organism in water, procedures for identifying new cases ofthe disease, and water treatment and control strategies for facilities where an outbreak hasoccurred.II. Disease RecognitionA. Causative Agent1. LEGIONELLA PNEUMOPHILA was first identified in 1977 by the CDC as the cause of anoutbreak of pneumonia that caused 34 deaths at a 1976 American Legion Convention inPhiladelphia. L. PNEUMOPHILA had undoubtedly caused previous pneumonia outbreaks,Microservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

but the organism's slow growth and special growth requirements prevented earlierdiscovery.2. The diseases produced by LEGIONELLA are called LEGIONELLOSIS. More than 34 speciesof LEGIONELLA have been identified, and more than 20 linked with human diseases. L.PNEUMOPHILA causes the pneumonia known as Legionnaires' disease and the flu-likePontiac fever. L. PNEUMOPHILA has also been implicated in wound infections, pericarditis,and endocarditis without the presence of pneumonia. Because the majority oflegionellosis is caused by L. PNEUMOPHILA, this chapter will deal exclusively with thatorganism. Cases where other species of LEGIONELLA are involved in disease requireactions similar to those to control Legionnaires' disease.3. The L. PNEUMOPHILA bacteria are gram-negative rods that exist in a number ofdistinguishable serogroups. Each serogroup contains further subtypes that have differentsurface structures on the cell membrane and can be distinguished by special tests.Evidence indicates that some LEGIONELLA serogroups are more virulent than others. L.PNEUMOPHILA serogroup 1 is the most frequently identified form of the bacteriumisolated from patients with Legionnaires' disease, although other serogroups and subtypesof the bacterium are frequently isolated from water sources. Serogroups 4 and 6 are thenext most frequently linked with disease.B. Symptoms1. Legionnaires' disease has an incubation period of two to ten days. Severity ranges from amild cough and low fever to rapidly progressive pneumonia and coma. Early symptomsinclude malaise, muscle aches, and slight headache. Later symptoms include high fever(up to 105 F), a dry cough, and shortness of breath. Gastrointestinal symptoms includingvomiting, diarrhea, nausea, and abdominal pain are common. The disease is treated witherythromycin or a combination of erythromycin and rifampin.2. Pontiac fever is a non-pneumonia, flu-like disease associated with, and likely caused by,the LEGIONELLA bacterium. This disease has an "attack rate" of 90% or higher amongthose exposed, and a short incubation period, 1-3 days. Complete recovery usually occursin 2-5 days without medical intervention. The factors that cause the same organism toproduce two illnesses with major differences in attack rate and severity are not known.C. IncidenceIn the U.S., Legionnaire's disease is considered to be fairly common and serious, and theLEGIONELLA organism is one of the top three causes of sporadic, community-acquiredpneumonia. Because it is difficult to distinguish this disease from other forms of pneumonia,many cases go unreported. Approximately 1,000 cases are reported annually to the CDC, but it isestimated that over 25,000 cases of the illness occur each year and cause more than 4,000deaths.D. Risk FactorsLegionnaires' disease is frequently characterized as an "opportunistic" disease that mostfrequently attacks individuals who have an underlying illness or weakened immune system. Themost susceptible include persons who are elderly, smokers, and immunosuppressed. IndividualsMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

with chronic obstructive pulmonary disease (COPD), organ transplant patients, and personstaking corticosteroid therapy are also at elevated risk. The attack rate for the average populationis approximately 5% or less. The fatality rate is similar to that of other forms of pneumonia,approximately 15%.E. DiagnosisCDC guidelines define two types of cases of Legionelloses, probable and confirmed. A PROBABLEcase of Legionnaire's disease is a person who experienced an illness clinically compatible withLegionnaire's and has a single antibody titer of 256 or higher (discussed below), and can beassociated with a population of individuals who have experienced confirmed cases of the disease(outbreak). A CONFIRMED case of LEGIONELLA requires a physician's diagnosis of pneumoniabased on a chest x-ray and positive laboratory test results. A laboratory test is necessary forconfirmation because the symptoms and x-ray evidence of Legionnaires' disease resemble thoseof other types of pneumonia. Various methods are used to confirm the presence of the disease.1. Culture of the Organism. The definitive laboratory method of confirming the presenceof the disease is by culturing viable cells of LEGIONELLA from sputum, bronchial washing,or autopsy on special media. Further identification of the cultured cells will identify thespecies and serogroup. Special tests may determine subtype of certain isolates. Thesensitivity of this test to detect the disease is reported to be about 70%.2. Urine Antigen Test. The detection of antigen from L. PNEUMOPHILA in the urine isconsidered a reliable measure of the disease. These antigenic materials may include L.PNEUMOPHILA cells or portions of cells in the urine during and after the disease. Thepresence of antigen in the urine is a strong indicator of the disease, and a patient mayhave a positive response for several months following the disease. The sensitivity of thistest is limited because the only commercially available urinary antigen test detects onlyserogroup 1 forms of L. PNEUMOPHILA. The CDC recommends only theradioimmunoassay (RIA) test because the latex antigen (LA) test has a high false-positiverate. Fortunately, 80-90% of the clinically diagnosed cases are caused by serogroup 1.The absence of a positive urinary test is not proof that a patient did not haveLegionnaires' disease, but merely indicates the absence of antigen in the urine at the timeof the test.3. Direct Fluorescent Antibody (DFA) Staining. Direct fluorescent antibody staining oflung aspirates can detect L. PNEUMOPHILA. However, this test is frequently negativeduring the initial stages of the disease because few organisms are present in the aspirateor sputum. This test also requires an antigen-specific reagent. There are a multitude ofserogroups and subtypes of L. PNEUMOPHILA, and a test will be negative if the exactantigen-specific reagent is not included.4. Serology (Antibody Titers)a. An increase in the antibody level in the serum of infected persons occurs severalweeks after the onset of the disease. A fourfold increase in the antibody titercoupled with a physician's diagnosis of pneumonia is considered a reliableindicator of disease. This is measured by comparing the antibody level four toeight weeks after onset (convalescent titer) to an initial (acute) titer at thebeginning of the disease. Pontiac fever also produces an elevated antibody titer,but the flu-like symptoms of this disease do not match those of Legionnaires'disease.b. Frequently only a convalescent titer has been measured from individuals who hadsymptoms of the disease. For situations in which these cases are associated withan outbreak of Legionnaires' disease, a single titer of 256 to 1 or higher isMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

generally used as a presumptive indication of disease (probable case). Antibodystrength is determined by the number of dilutions of serum which elicit a positiveantibody response. The reciprocal value of the number of dilutions is the antibodytiter. For example, an antibody titer of 256 means a positive antibody test of thepatients's serum following serial dilutions of 1:2, then 1:4, then 1:16, etc., untilthe 1:256 dilution point is reached.c. The indirect fluorescent antibody (IFA) test is the accepted diagnostic tool fordemonstrating L. PNEUMOPHILIA exposure. Another widely used test of antibodyresponse is the enzyme-linked immunosorbent assay method (ELISA). CDCbelieves that direct comparison of results between IFA and ELISA is not reliablebecause there are insufficient data to compare the two. The ELISA method hasgained wide medical acceptance as a useful means of demonstrating exposure toLEGIONELLA.F. Transmission1. The likelihood of contracting Legionnaires' disease is related to the level of contaminationin the water source, the susceptibility of the person exposed, and the intensity ofexposure to the contaminated water. Disease transmission usually occurs via inhalation ofan aerosol of water contaminated with the organism. Aspiration of contaminated waterinto the lungs may also cause the disease. In the Philadelphia Legionnaires' diseaseoutbreak, the hotel's cooling tower was identified as the likely source of the disease,although domestic water sources were not evaluated.2. The disease has been associated with domestic hot-water systems in a number ofoutbreaks. In many instances it has been difficult to identify a likely source foraerosolization of the suspected water source. Although transmission of the disease otherthan through direct inhalation of aerosols may occur, the mechanisms are not clearlyunderstood. The organism requires water, and the disease cannot occur in the absence ofa contaminated water source. There is no evidence that the disease can be transmittedfrom one person to another.III. Source IdentificationA. Conditions that Promote Growth1. L. PNEUMOPHILA bacteria are widely distributed in water systems. They tend to grow inbiofilms or slime on the surfaces of lakes, rivers and streams, and they are not eradicatedby the chlorination used to purify domestic water systems. Low and even nondetectablelevels of the organism can colonize a water source and grow to high concentrations underthe right conditions.Conditions that promote growth of the organism include heat, sediment, scale, andsupporting (commensal) microflora in water. Common water organisms including algae,amoebae, and other bacteria appear to amplify LEGIONELLA growth by providingnutrients or harboring the organism. Because of its ability to remain viable in domesticwater systems, it is capable of rapid multiplication under the proper conditions.2. Water conditions that tend to promote the growth of LEGIONELLA include:o stagnation;o temperatures between 20 and 50 C (68 - 122 F) (The optimal growth range is35 - 46 C [95 - 115 F]);Microservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

ooopH between 5.0 and 8.5;sediment that tends to promote growth of commensal microflora; andmicro-organisms including algae, flavobacteria, and PSEUDOMONAS, which supplyessential nutrients for growth of LEGIONELLA or harbor the organism (amoebae,protozoa).B. Common Sources of Contaminated Water1. Water sources that frequently provide optimal conditions for growth of the organismsinclude:o cooling towers, evaporative condensers, and fluid coolers that use evaporation toreject heat. These include many industrial processes that use water to removeexcess heat;o domestic hot-water systems with water heaters that operate below 60 C (140 F)and deliver water to taps below 50 C (122 F);o humidifiers and decorative fountains that create a water spray and use water attemperatures favorable to growth;o spas and whirlpools;o dental water lines, which are frequently maintained at temperature above 20 C(68 F) and sometimes as warm as 37 C (98.6 F) for patient comfort; ando other sources including stagnant water in fire sprinkler systems and warm waterfor eye washes and safety showers.2. Water stored below 20 C (68 F) is generally not a source for amplified L. PNEUMOPHILAlevels. However, high levels of bacteria have been measured in the water supplying icemachines. The source of amplification in this case was thought to be heat from thecondenser coil of the ice maker to the cold water supply. However, no cases ofLegionnaires' disease have been linked to consumption of ice made from contaminatedwater.C. Monitoring1. Air. An air sample applied to special culture plates by an Andersen-type samplersometimes demonstrates the presence of the organism in the air. However, negativeresults are frequent because of the difficulty in maintaining viability of the organism onthe culture plates. Air sampling for LEGIONELLA is strongly not recommended as a meansof measuring potential exposure because of the high likelihood of false negatives.2. Water. Analysis of water samples from a source suspected of being contaminated with L.PNEUMOPHILA is a valuable means of identifying potential sources of the disease. Aqualified microbiological laboratory experienced in LEGIONELLA detection can determinethe number of organisms present in colony forming units (CFU) per volume of water andcan identify the different serogroups of LEGIONELLA pneumophila in the sample.Appendix III:7-2 provides details on the collection, storage, and shipping of watersamples.D. Microbiological Analysis of Water Samples1. Cultured Samples. Water samples are cultured on special buffered charcoal yeastextract (BCYE) culture media. Selective isolation processes to eliminate other microbialovergrowth can determine the number of CFU of L. PNEUMOPHILA per milliliter of water.Microservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

This process of growth and isolation is time-consuming, and results typically require 7-14days from the time of submission.2. Cultured samples can also be analyzed to identify specific serogroups. Matching the sameserogroup and subtype of organism in the patient as found in a water source isconsidered strong evidence of an associated link.3. Direct Fluorescence Antibody (DFA). The number of organisms in a water samplecan also be determined via direct fluorescence antibody (DFA) conjugate tests that stainthe organism with a fluorescent dye. This test is unable to distinguish between live anddead bacteria and may also have some cross-reactivity with other bacteria. Sample resultscan be available in one or two days, and this method can be useful in screening watersamples. Use caution, however, in interpreting the results since the potential exists forboth false positive and negative results.4. DNA Amplification. A relatively new method for rapid, specific detection of theorganism in water employs a polymerase chain reaction (PCR) process to amplify andthen detect portions of DNA unique to L. PNEUMOPHILA. This method can produce resultsin 1 day, and preliminary evidence indicates that its sensitivity and specificity arecomparable to those of cell culture, which can take 10-14 days to obtain results. Furthertesting may lead to acceptance of this technique as the method of choice for monitoringwater sources for contamination.E. Interpretation of Sample Results1. The probability of infection with L. PNEUMOPHILA is a function both of the intensity of theexposure dose and the level of host susceptibility. Because total eradication ofLEGIONELLA may not be possible, an acceptable control strategy is to minimize thenumber of organisms present in a water source. Ample evidence indicates thatLEGIONELLA levels are readily controllable. A survey of over 1,000 cooling towersindicates that approximately 60% contained nondetectable levels of L. PNEUMOPHILAwhen measured by DFA analysis for the number of organisms per milliliter of water(detection limit is 10 bacteria per milliliter of water). In another survey of 663 coolingtowers, 57% contained LEGIONELLA that were not detected when measured by culture(detection limit less than 1 CFU/mL). Other studies of domestic hot-water sources indicatethat although the organism is common, especially in large hot-water systems, practicalcontrol measures can limit the potential for amplification.2. A private consulting firm and microbiological laboratory, PathCon Inc. of Norcross,Georgia, has introduced suggested guidelines for control of the organism based on thenumber of CFU of L. PNEUMOPHILA per milliliter of water (Appendix III:7-3.) Theseguidelines vary depending on the water source, a recognition by the authors that dose isrelated both to the potential for exposure and to concentration. For example,recommended exposure limits for contaminated water from a humidifier, which wouldinvolve direct exposure to an aerosol are lower than for a cooling tower where theopportunity for exposure is normally less. Work operations such as maintenance oncooling towers may involve direct exposure to cooling tower mist, and precautions tominimize exposure are always necessary. The authors recognize that these guidelines arebased on limited data, but they represent the best available information and must sufficeuntil the dose effect of L. PNEUMOPHILA is better understood.IV. Investigation ProtocolA. Community Health ConcernsMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

It is important to remember that an outbreak of Legionnaires' disease among workers may haveits origin in the community and may not be related to the work environment. A Legionnaires'outbreak is both an occupational and a public-health concern, and the investigation may includelocal public health departments and the Centers for Disease Control (CDC). To minimizeemployee risk and maximize the effectiveness of effort, close coordination among OSHA, otherpublic agencies, and the employer is imperative.B. Types of Investigations1. The course of action chosen during an investigation of a facility should be based on thedegree of certainty that the site is the source of a reported illness. For this reason, twoinvestigation protocols are based on differing levels of suspected risk for exposure toLEGIONELLA. It is important to remember that these procedures are provided only toassist in the investigation of potential Legionnaires' cases. Individual circumstances mayrequire changes in the investigation. All cases require sound professional judgment indeciding the appropriate course of action.2. A level-one investigation may be initiated when there is a probable basis for suspectingthat workplace water sources are contaminated with LEGIONELLA, or when there isinformation that one case of Legionnaires' disease may exist. A level-two investigationshould be conducted when more then one possible case of Legionnaires' disease has beenreported at a facility.3. If two or more cases of the disease can be attributed to a work site, assume that aLegionnaires' disease outbreak has occurred. If evidence indicates that the outbreak isstill in progress (that is, at least one of the cases has occurred in the last 30 days),prompt actions should be undertaken to provide maximum protection to employees andeliminate the hazard. Appendix III:7-5 includes examples of actions required to controlwater sources where an outbreak has occurred.4. Both investigations follow the same general pattern and include a preliminary openingconference, a walk-through of the facility to conduct a physical assessment of the watersystems, a more detailed examination of the systems including a review of maintenancerecords, assessment of findings, and a closing conference to present control actionsbased on the findings.C. Level-One InvestigationUse the following procedure when Legionnaires' disease may be related to the work environment.1. Step 1. OBTAIN AN OVERVIEW OF ALL WATER SYSTEMS AT THE FACILITY.a. A facilities engineer or experienced member of the building maintenance staffshould be available to explain system operation and assist in the walkthroughinvestigation. This person should have a working knowledge of the system'sdesign and current operation.b. The overview of the water systems should include plumbing systems, heatingventilating-air-conditioning (HVAC) systems, and other water reservoirs. A reviewof the plumbing system should include both hot and cold domestic water systems,water heaters, distribution pipes, water coolers, water treatment equipment,connections to process water systems protected (or unprotected) by backflowpreventers, and storage tanks.c. The HVAC system review should include cooling towers, evaporative condensers,fluid coolers, humidifiers, direct evaporative air-cooling equipment, indirectMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

evaporative air-cooling equipment, air washers for filtration, etc. Note the locationof the fresh-air intakes of the building's air-handling units relative to water sourcessuch as the cooling towers.d. Investigate other potential sources of employee exposure including decorativefountains, plant misters, whirlpools, spas, tepid-water eye-washes and safetyshowers, humidifiers, and water for cooling industrial processes.e. Review maintenance records on water systems including water heaters andcooling towers. The records should include temperature checks of domestic water,visual and physical checks of cooling towers, and reports of cooling-tower waterquality assessment and chemical treatment.f. Identify the locations of portions of the system in which water is allowed tostagnate such as storage tanks or unused plumbing pipe sections ("dead legs"), orinfrequently used faucets. Check for cross-connections between domestic andprocess water systems, and note the condition and type of back-flow preventiondevices.g. Investigate recent major maintenance or changes in the system's operation.Determined if there were recent or frequent losses of water pressure from theincoming water supply due to line breakage or street repairs. The failure of aback-flow prevention device under loss of pressure can contaminate the system.2. Step 2. CONDUCT A WALK-THROUGH INVESTIGATION OF THE FACILITY.a. Equipment you will need includes a thermometer for measuring watertemperatures, a flashlight, and a film or video camera to record observations.Measure and record the temperature of water drawn from each storage-typewater heater in the facility. This temperature may be significantly below the waterheater's gauge temperature because of heat stratification. Note the presence ofrust and scale in this water.b. Record the maximum temperature of water at faucets connected to each waterheater on the system. Record temperatures at locations near, intermediate, anddistant from the heaters. It may be necessary to run the water for several minutesbefore it reaches a temperature maximum.c. Examine the water temperature and the potential for stagnation of cold-waterstorage tanks used for reserve capacity or to maintain hydrostatic pressure. Theseshould be protected from temperature extremes and covered to preventcontamination. Record the temperature of the domestic cold-water lines at variouslocations within the facility. Note both the initial temperature and the finalequilibrium temperature on the cold-water line, and record the time required toreach equilibrium, because this can be an indicator of the amount of stagnation inthe system.d. Evaluate cooling towers, evaporative condensers, and fluid coolers for biofilmgrowth, scale buildup, and turbidity. Record the location of the tower relative tofresh-air intakes, kitchen exhausts, leaves, plant material, or other sources oforganic material that might contribute to the growth of the organism.e. Record the general condition of the cooling tower. Determine the presence andcondition of drift eliminators, which are designed to limit the vapor release fromthe units, along with the basin temperature of the water in the cooling tower if itis currently being operated. If the cooling tower is operating and is suspected ofbeing contaminated, wear appropriate respiratory protection in the form of a halfface piece respirator equipped with a HEPA or similar type of filter capable ofeffectively collecting one-micron particles during the examination of the system.f. Note the location and evaluate the condition of the sumps for the coolingtower(s), evaporative condenser(s), and fluid cooler(s). These sumps areMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]

sometimes located indoors to protect them from freezing. Record the locations ofany cross-connections between the cooling tower water system and any domesticwater system. These may supply a back-up source of cool water to refrigerationcondenser units or serve to supply auxiliary cooling units. The lack of a regularmaintenance schedule or water-treatment program for a cooling tower orevaporative condenser system strongly suggests a potential for LEGIONELLAcontamination.3. Step 3. ASSESS THE RESULTS OF THE WALKTHROUGH INVESTIGATION TO DETERMINETHE COURSE OF ACTION. If no potential problems are identified, the operatingtemperatures measured at water heaters are 60 C (140 F) or above, and the deliverytemperature at distant faucets is 50 C (122 F) or higher, no further action will benecessary. However, if the system is poorly maintained and operating temperatures arebelow recommended minimums, then recommendations for corrective action should bemade.4. Step 4. RECOMMEND CONTROL ACTIONS.a. Details of suggested control actions are discussed in Section E. These actions mayinclude disinfection of the domestic water system via heat treatment, chlorination,or other means, and cleaning and disinfecting the cooling tower system accordingto the Wisconsin Division of Health protocol for "Control of LEGIONELLA in CoolingTowers" or a similar process for cleaning heat rejection systems that follows soundpractices to minimize potential for LEGIONELLA growth.b. Additional actions may include eliminating dead legs in the plumbing system,insulating plumbing lines and installing heat tracing to maintain propertemperatures in the system, eliminating rubber gaskets, and removing orfrequently cleaning fixtures such as aerators and shower heads.c. Corrective actions limited to raising the water heater temperature withoutevaluating the system for points of stagnation, heat loss and gain, crosscontamination, and other factors that contribute to growth are generally notsufficient.d. For a level-one investigation it is not recommended that water samples becollected to confirm the presence of LEGIONELLA in the system. The absence ofproper operating conditions alone is sufficient for assuming that the water systemcan pose an unnecessary risk to the employees. Take water samples after thecompletion of the control actions to confirm that the corrective measures weresuccessful. The employer may also want to obtain samples before startingcorrective actions to assess the extent of the problem.e. The employer should take necessary corrective actions even if the results ofpresampling are negative. Water sampling can produce false negatives, acontaminated portion of the system may have been missed, and the absence ofLEGIONELLA organisms at the time of sampling does not insure that the systemwill remain negative.f. If, after control actions, the LEGIONELLA levels in a water source exceed theguidelines in Appendix III:7-3, re-examine the water system to determine ifpotential contamination points within the system were overlooked and reassesscontrol procedures to determine if they were performed properly. Repeat theprocedures as needed until contamination levels meet the guidelines.D. Level-Two InvestigationA level-two investigation is similar to a level-one investigation with several additional steps.Supplemental actions include: (1) medical surveillance of all employees currently on sick leave toMicroservices Fergo S.L. C/ Islandia, 2 (Edificio Coblanca 26) Local 20 03502 Benidorm CIF nº B- 54262100Tfo. nº 966811917Fax nº [email protected]


OSHA TECHNICAL MANUAL Section III: Chapter 7 LEGIONNAIRES' DISEASE Table of Contents: I. Introduction II. Disease Recognition III. Source Identification IV. Investigation Protocol V. Controls VI. Bibliography List of Appendices Appendix III:7-1. Employee Awareness Program Appendix III:7-2. Physical Survey and Water Sampling Protocol