To: Directors of Environmental Health/ Chief Environmental Health Officers of London, Metropolitan, District and Unitary Authorities and Chief Executives of County Councils.

For the attention of: Environmental Services /Trading Standards /Fire Authorities /Other

This circular gives advice to local authority enforcement officers

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CONTROL OF LEGIONELLA IN WET COOLING SYSTEMS

INTRODUCTION

1 HELA Circular 40/4 contained details of a two stage project in respect of the Control of Legionella in Wet Cooling Systems. The project, which had been delayed until the availability of the new ACoP/guidance, can now begin.

2 A copy of 'Legionnnaires' disease: The control of legionella bacteria in water systems' Approved Code of Practice and Guidance' has been sent to all local authorities (see HELA LAC 46/2).

BACKGROUND

3 There has been a rising trend over recent years of outbreaks of Legionnaires' Disease associated with wet cooling systems (cooling towers and evaporative condensers). These usually result in serious cases of infection and sometimes fatalities. They also cause considerable public concern and absorb substantial resources from the enforcing authorities. Poor compliance with the requirements of the COSHH regulations and the previous Approved Code of Practice 'The prevention or control of legionellosis (including legionnaires' disease)' have frequently been found to give rise to the potential conditions in which outbreaks can occur.

4 Since 1997, there has been a programme of action to improve levels of compliance. An essential element has been inspections of installations and a high level of enforcement as a consequence. Local authorities are now joining HSE in furthering this effort and are participating in a two stage project starting in early 2001.

THE PROJECT

Stage 1 - mailing of self audit proformas

5 Stage 1 of the project comprises mailing a self-audit proforma to all (LA enforced) premises with appropriate installations notified under the Notification of Cooling Tower and Evaporative Condenser Regulations 1992, asking occupiers to complete and return the proformas. The proforma (see pages 3 to 8) and sample letter (see pages 9 to 10) are included in this circular.

Stage 2 - follow up inspections

6 Stage 2 consists, where practicable, of follow up inspections to those occupiers where the proforma indicated poor compliance with the ACoP or who did not reply at all. An inspection proforma (see pages 11 to 16) and enforcement guidelines (see page 17) are included in this circular.

Copies of any completed inspection proformas should be returned to LAU marked for the attention of Mark Thomas.

AIMS

7 The overall aim of the exercise is to reduce the number of outbreaks from wet cooling systems (cooling towers and evaporative condensers) by:

i) Increasing employers' awareness of their legal responsibilities with respect to the Approved Code of Practice (ACoP), 'Legionnaires' Disease: the control of Legionella bacteria in water systems.'

ii) Pursuing active enforcement where there is inadequate compliance with the ACoP.

MEASURE OF SUCCESS

6 The primary measure of success will be improved standards of compliance with the ACoP. This will have an intended secondary effect of reducing the number of outbreaks, although it will only be possible to assess this after a number of years have elapsed.

TRAINING AND COMPETENCY REQUIREMENTS

7 Some LA enforcement officers may need to be trained to carry out inspections of wet cooling systems with respect to the control of Legionella. LAU has already facilitated a number of training courses for local authority enforcement officers and further courses are planned. A training video 'Control of Legionella: Part 1 Cooling Towers' is also available via LAU.

CONTROL OF LEGIONELLA AUDIT PROFORMA

INTRODUCTION: This document is an audit sheet designed to assist persons in control of cooling systems which incorporate cooling towers or evaporative condensers to assess their level of compliance with the requirements of the Control of Substances Hazardous to Health Regulations 1999 and the (revised) Approved Code of Practice (ACoP) - 'Legionnaires' disease: the control of legionella bacteria in water systems' THIS AUDIT IS NOT A RISK ASSESSMENT IN ITSELFTHIS PROFORMA IS NOT A RISK ASSESSMENT. IT MERELY ADDRESSES THE MOST IMPORTANT ASPECTS OF THE ACoP, AND IS DESIGNED AS A METHOD OF CHECKING COMPLIANCE.WHEREVER FURTHER ACTION IS REQUIRED IT WILL BE NECESSARY TO REVIEW THE RELEVANT PART(S) OF YOUR RISK ASSESSMENT AND/OR WRITTEN SCHEME OF PRECAUTIONS.It is designed to be an audit to assess the adequacy of the existing assessment and to highlight areas where further action is necessary. Further information is available in the new ACoP which now includes guidance formerly given in the document HS(G)70, 'The Control of Legionellosis (including Legionnaires Disease).'
Name and address of company:
1. Cooling system:
2. Date:
3. Audit carried out by:
4. Next review due:
NOTIFICATION	YES /NO		FURTHER ACTION REQUIRED YES /NO
5. Is the cooling tower/evaporative condenser notified to the LA?
The Notification of Cooling Towers and Evaporative Condenser Regulations 1992 require that all of these devices are registered with the local authority. If yours is not, contact the environmental health department of your local authority for the required registration form.

RISK ASSESSMENT	YES /NO		FURTHER ACTION REQUIRED YES /NO
6. Is there a written risk assessment for the system?
7. Does it contain an up to date schematic plan of the system?
8. Does it contain details of the precautions to be taken?
9. Does it contain instructions for the operation of the system?
10. Does the assessment conclude that there is a significant risk?
11. Does the assessment consider the tower's physical condition?
12. Does it consider the tower's positioning?
13. Does it consider the population density near the premises?
14. Does it consider any 'at risk' groups of persons?
Notes: Question 10 - For systems incorporating a cooling tower or evaporative condenser there will automatically be a risk of exposure and a written assessment must be recorded. The degree of risk will depend on a variety of factors including the condition of the tower, the population density within the vicinity of the premises (potential numbers of persons exposed) and whether there are any particularly susceptible persons nearby.

hghghg
SYSTEM SCHEMATIC	YES /NO		FURTHER ACTION REQUIRED YES /NO
15. Does it show all system control valves?
16. Does it show standby plant (spare pumps etc)?
17. Does it show any associated storage tanks?
18. Does it show system bleed valve?
19. Does it show chemical dosing pumps and injection points?
20. Does it show system drain valve?
21. Does it show the origin of the water supply?
hghghg
PRECAUTIONARY MEASURES	YES /NO		FURTHER ACTION REQUIRED YES /NO
22. Has elimination or replacement with a lower risk system been properly considered?
hghghg
It should be noted that the precautions to be taken are required to protect persons against EXPOSURE to the legionella bacteria. The COSHH Regulations set out a hierarchy of measures to eliminate or reduce risks so far as is reasonably practicable. The first matter which should be considered is substitution of the system for a lower risk device such as closed chillers of air blast cooling where this is reasonably practicable. If this cannot be done, the necessary measures for control are more than just a chemical treatment of the water. They consist of a whole range of measures including design, operation, maintenance, monitoring and management and should include the provision of drift eliminators.
hghghg
CLEANING AND DISINFECTION	YES /NO		FURTHER ACTION REQUIRED YES /NO
23. Is there a written cleaning and disinfection procedure?
24. Is it carried out at least every six months?
hghghg
25. If not, why not and how often?
26. Does it specify chlorine level at start of pre-clean chlorination?
27. Does it specify contact/circulation time?
28. Does it specify chlorine level at end of pre-clean chlorination?
29. Does it give the method for cleaning all accessible parts?
30. Does it specify chlorine levels at start of post-clean chlorination?
31. Does it specify contact/circulation time?
32. Does it specify chlorine level at end of post-clean chlorination?
33. Is the removal of the tower fill/pack for cleaning and disinfection specified in the assessment?
34. If not, why not?
35. Are they removed for cleaning and disinfection in practice?
36. Are there suitable health and safety procedures for carrying out cleaning and disinfection?
hghghg

ON-GOING WATER TREATMENT	YES /NO		FURTHER ACTION REQUIRED YES /NO
37. Is a water treatment programme in place?
38. Does it use chemicals to control scale?
39. Does it use chemicals to control corrosion?
40. Does it use chemicals to control bacterial and algae (biocides)
41. Are alternating biocides used?
42. Are the chemicals automatically dosed?
43. Is there an automatic bleed to control dissolved solids?
hghghg
CORRECT AND SAFE OPERATION	YES /NO		FURTHER ACTION REQUIRED YES /NO
44. Are there procedures for circulation of all parts once per week?
45. Is there a shutdown of the installation at least once per year?
46. If yes, how long does it last? <1 week r 1 week - 1 month r >1 month r
47. Are there procedures for start up after shutdowns?
48. Instructions for draining during long shutdowns?
49. Instructions regarding valve settings for normal operation?
50. Procedures for switching duty/standby pumps.

hghghg
MONITORING AND RECORDS	YES /NO		FURTHER ACTION REQUIRED YES /NO
51. Daily check to ensure conformance with operating procedures?
52. Daily visual check made on the cleanliness of the system water?
53. Chemical water quality checks carried out at least monthly?
54. System physical condition checks carried out at least weekly?
55. Dipslide tests taken at least weekly?
56. If not how often?
57. Are legionella tests carried out every quarter?
58. If not, how often?
59. Records of all tests undertaken maintained?
60. Recommendations for remedial action recorded?
61. Completion of remedial action recorded?
62. Are there records of plant usage?
hghghg

PROGRAMME MANAGEMENT	YES /NO		FURTHER ACTION REQUIRED YES /NO
63. Is there a responsible person nominated in writing?
64. Is there an appointed deputy?
65. Are the duties of all persons involved clearly defined?
66. Are all persons involved adequately trained?
67. Are the responsibilities of the occupier and consultant(s) clearly defined?
68. Have the other relevant health and safety issues - COSHH assessments for chemicals, safe access etc been addressed?
hghghg

PHYSICAL CONDITION AND DESIGN	YES /NO		FURTHER ACTION REQUIRED YES /NO
69. Are the drift eliminators suitable, in good condition and effective?
70. Is the system water in good condition?
71. Is the sump free from sediment?
72. Are all visible surfaces free from slime or algae?
73. Are all visible surfaces free from scale deposits?
74. Are all visible surfaces free from corrosion?
75. Is the water flow even across the whole of the tower fill?
76. Have all the dead legs or poor flow areas been eliminated?
77. Has all redundant plant been isolated from the system?
78. Are all pipe runs as short and direct as possible?
79. Is the tower constructed of impervious materials ?
80. If constructed of wood, is this in good condition?
hghghg
Drift eliminators should be of a multi-pass type. Old style single-pass eliminators are not acceptable. There should be no readily apparent emission of droplets in the exit airstream and where it is possible to look through the air path (from inlet to outlet) there should be no daylight visible. Eliminators should be checked for damage and correct location frequently as they are a vital control measure for minimising exposure of persons to a potentially contaminated aerosol. Negative answers to questions 69 to 80 would suggest that control of water is poor, and that the control measures are not effective and require a thorough review.

COOLING TOWER/EVAPORATIVE CONDENSER DETAILS

Manufacturer:		Model:
Type: (see diagram below)
Year of manufacture:

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CONTROL OF LEGIONELLA AUDIT PROFORMA

Please complete the details of any contractors below

(a) Ongoing water treatment contractor:

Name:	hghghg
Address:	hghghg
Contact:	hghghg
Phone:	hghghg

(b) Cleaning and disinfection contractor:

Name:
Address:
Contact:
Phone:

(c) Risk assessment

Name:
Address:
Contact:
Phone:

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Environmental Health Dept.,
X Town Council

Our Ref:

Dear Sirs

CONTROL OF LEGIONELLA IN WET COOLING SYSTEMS

According to current Local Authority records, you operate a cooling tower or evaporative condenser. If not properly looked after such installations can pose a serious risk from outbreaks of legionnaire's disease, which is a serious disease and can be fatal in approximately 12% of all cases. Usually, public concern is very high during outbreaks.

Recent investigations by the Health and Safety Executive (HSE) and Local Authorities into the standards of operation of cooling towers and evaporative condensers at workplaces have highlighted a lack of awareness of:

1) the requirements for suitable written risk assessments of individual water cooling systems in accordance with the HSE Approved Code of Practice*

2) the need for a written scheme including details of:

a) measures to maintain and monitor water quality;

b) maintenance and monitoring of equipment performance; c) appointment of competent responsible persons for implementing these controls.

3) the importance of proper maintenance, with respect to matters like the need for removal of pipework "dead legs" and removal of the pack for cleaning.

4) the need to keep written records of:

a) risk assessment findings;

b) scheme of operation/maintenance controls;

c) monitoring of water quality;

d) equipment maintenance.

5) the requirement for notification of individual cooling towers/evaporative condensers to the relevant local authority.

It has also frequently been found that operators of water cooling towers/systems are unclear as to the precise terms of their contracts with their water treatment company. Some water treatment companies only have a remit limited to provide biocidal treatment of the water, with no-one responsible for implementing the other equally important areas of control (such as the checking and cleaning of drift eliminators, the maintenance of tower condition etc.)

The 'X Town Council' is contacting all operators of installations to check standards of assessment and control. Would you please advise therefore, me within 28 days of the steps you have already taken or will be taking, to achieve compliance with your legal requirements. I have enclosed a self audit proforma which should help you assess the adequacy of your existing assessment/arrangements and highlight areas where further action is necessary. It would be helpful if, with your reply, you would return a completed copy of this, together with an outline plan of your premises, showing where the towers or condensers are located.

You are advised that the local authority and HSE will be visiting a number of operators of such plant in due course and where the required standards are not met, appropriate enforcement action will be taken.

A copy of HSE leaflet IAC(L)27 "Legionnaires Disease" is enclosed.

Yours faithfully

Environmental Health Department

*Guidance on the prevention and control of legionellosis is now contained in the revised HSE Approved Code of Practice (ACoP) 'Legionnaires' Disease: the control of Legionella bacteria in water systems' which combines both the previous ACoP and information previously given in the document HS(G) 70. This available from HSE Books, PO Box 1999, Sudbury, Suffolk CO10 6FS; Tel: 01787 881165.

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CONTROL OF LEGIONELLA IN WET COOLING SYSTEMS

VISIT PROFORMA

INTRODUCTION: This proforma should be completed as part of normal preventive inspections of premises which operate cooling towers or evaporative condensers. Where premises have more than one cooling tower system, a separate proforma should be completed in each case.

When completed, please copy and return this proforma to:
Mark Thomas, HSE, LAU, 7SW Rose Court, 2 Southwark Bridge, London SE1 9HS

VISIT DETAILS

Company Name..............................................................................................................................

Address...........................................................................................................................................

..........................................................................................................................................................

Appointed Person..........................................................................................................................

Telephone.......................................................................................................................................

1 Cooling System.............................................................. 2 Date................................................

3 Inspectors Name............................................................ 4 Local Authority...............................

	YES	NO	N/A
5 Is the cooling tower/evaporative condenser notified to the LA?
RISK ASSESSMENT - GENERAL
6 Is there a written risk assessment for the system? (If answering 'No' answer Q7 then go to next section)
7 Is there an up to date schematic plan of the system?
8 Does it contain details of the precautions to be taken?
9 Does it contain instructions for the operation of the system?
10 Does the assessment conclude that there is a significant risk?
11 Does the assessment consider the tower's physical condition?
12 Does it consider the tower's positioning?
13 Does it consider the population density near the premises?
14 Does it consider any 'at risk' groups of persons?
SYSTEM SCHEMATIC (If answering 'No' to Q7 go to Q22)
	YES	NO	N/A
15 Does it show all system control valves?
16 Does it show standby plant (spare pumps etc)?
17 Does it show any associated storage tanks?
18 Does it show system bleed valve?
19 Does it show chemical dosing pumps and injection points?
20 Does it show system drain valve?
21 Does it show the origin of the water supply?
PRECAUTIONARY MEASURES
	YES	NO	N/A
22 Has elimination or replacement with a lower risk system been properly considered?
CLEANING AND DISINFECTION
	YES	NO	N/A
23 Is there a written cleaning and disinfection procedure? (If answering 'no', answer Qs. 24 & 25, then go to Q33.)
24 Is cleaning and disinfection carried out at least every six months?
25 If not, why not and how often?
26 Does it specify chlorine levels at start of pre-clean chlorination?
27 Does it specify contact/circulation time?
28 Does it specify chlorine levels at end of pre-clean chlorination?
29 Does it give the method of cleaning all accessible parts?
30 Does it specify chlorine levels at start of post-clean chlorination?
31 Does it specify contact/circulation time?
32 Does it specify chlorine level at end of post-clean chlorination?
33 Is the removal of the tower/fill pack for cleaning and disinfection specified in the assessment?
34 Is it removed for cleaning and disinfection in practice?
35 If not why not?
ON-GOING WATER TREATMENT
	YES	NO	N/A
36 Is a water treatment programme in place? (if answering 'No' go to Q44)
37 Does it use a scale inhibitor?
38 Does it use a corrosion inhibitor?
39 Does it use biocides (to control algae and bacteria)?
40 Are alternating biocides used?
41 Are oxidising biocides (chlorine or bromine) used?
42 Are non-oxidising biocides used?
43 Are the chemicals automatically dosed?
44 Is there an automatic bleed to control dissolved solids?
CORRECT AND SAFE OPERATION
	YES	NO	N/A
45 Is the plant usually operated
(a) Continuously (ie 7 days per week/24 hrs per day)?
(b) 24 hrs per day, throughout working week?
(c) Day shift(s) only, throughout the working week?
(d) On standby?
(e) Seasonally?
46 Does it cycle on and off automatically?
47 Are there procedures for circulation of all parts once a week?
48 Is there a shutdown of the installation at least once per year?
49 If yes, how long does it last? <1 week r 1 week - 1 month r >1 month r
50 When does the shutdown usually occur?
51 Are there procedures for start up from shutdowns?
52 Instructions for draining during long shutdowns?
53 Instructions regarding valve settings for normal operation?
54 Procedures for switching duty/standby pumps?
MONITORING RECORDS
	YES	NO	N/A
55 Daily check to ensure conformance with operating procedures?
56 Daily visual checks made on the cleanliness of the system water?
57 Chemical water quality checks carried out at least monthly?
58 System physical checks carried out at least weekly?
59 Dipslide tests taken weekly?
60 IF NOT, HOW OFTEN?
61 Taken by: Occupier r WT Contractor r Both r
62 Are legionella tests carried out quarterly?
63 IF NOT, HOW OFTEN?
64 Records of all tests undertaken maintained?
65 Recommendations for remedial action recorded?
66 Completion of remedial action recorded?
67 Are there records of plant usage?
PROGRAMME MANAGEMENT
	YES	NO	N/A
68 Is there a responsible person nominated in writing?
69 Is there an appointed deputy?
70 Are the duties of all persons involved clearly defined?
71 Are all persons involved adequately trained?
72 Are the responsibilities of the occupier and consultant(s) clearly defined?
73 Have the other relevant health and safety issues - COSHH assessments for chemicals, safe access etc been addressed?

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COOLING TOWER/EVAPORATIVE CONDENSER DETAILS

Manufacturer:	Model:
Serial Number:	Year of manufacture:
Type (see diagram):

PHYSICAL CONDITION AND DESIGN
	YES	NO	unable to assess
74 Are the drift eliminators suitable, in good condition and effective?
75 Is the system water in good condition?
76 Is the sump free from sediment?
77 Are all visible surfaces free from slime or algae?
78 Are all visible surfaces free from scale deposit?
79 Are all visible surfaces free from corrosion?
80 Is the water flow even across the whole of the tower fill?
81 Have all the deadlegs or poor flow areas been eliminated?
82 Has all redundant plant been isolated from the system?
83 Are all pipe runs as short and direct as possible?
84 Is the tower constructed from impervious materials?
85 If constructed of wood, is this in good condition?
86 Please complete the details of any contractors below:
A) On going water treatment contractor
Name:
Address:
Telephone:
Contact:
B) Cleaning and disinfection contractor:
Name:
Address:
Telephone:
Contact:
C) Risk assessment:
Name:
Address:
Telephone:
Contact:
87 Action proposed NFA r ADV r LETT r IN r PN r PR r
88 Please add any other useful information (use additional sheet if necessary)

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ENFORCEMENT GUIDELINES (Legionella)

1 The NCTEC Regulations, HSW Act, and in particular COSHH, may all be used for HSE enforcement. Both notices and prosecutions should be considered, if the precautionary measures are manifestly below the standard outlined in the ACoP. Depending on circumstances the following actions may be appropriate:

• Failure to notify under the NCTEC Regulations - improvement notice (IN).
• No or inadequate assessment under COSHH - IN. The requirement for a system schematic plan and responsible person should be listed in the schedule, where these do not exist.
• No appointed responsible person, but risk assessment otherwise adequate - letter.
• No system schematic plan, but risk assessment otherwise adequate - generally a letter, but for complex systems an IN may be appropriate.
• Serious risk of infection arising from the absence of or an inadequate assessment along with no water treatment programme and no evidence of cleaning and disinfection procedures - PN and/or prosecution.
• Failure to provide safe access - IN.
• Excessive organic contamination and/or presence of excessive scale in the pond - IN to require immediate shock dosing, followed up by thorough cleaning and disinfection or immediate cleaning and disinfection.
• Absence of, or clearly defective, drift eliminator - IN.
• A clearly identified risk from the presence of organic contamination and absence of, or clearly defective, drift eliminator - PN and/or prosecution.

Even if occupiers comply with notices issued according to the above guidelines, over a longer term, cumulative evidence may emerge of consistent failure to manage the system. Consideration of prosecution should then be given even if infringements at any one particular time are not the most serious.

Water treatment companies

Enforcement action should also be considered against water treatment companies where they are either clearly lacking in competence, negligent or have issued misleading documentation which indicates that a system is properly controlled under COSHH, when it manifestly is not.