Cooling Tower Inspection

• Site

• Location
  Address

• Conducted on

  Date

• Prepared by

• Persons present

• Number of towers:

• A) Cooling Tower (warm water is discharged against an air stream causing some evaporation/air saturation cooling water)

• B) Evaporative Condenser (refrigerant in pipes is condensed by air movement/water sprays over its surface)

• 1) Induced Draught Counterflow (fan at the top pulls air through tower and out at the top - air and water oppose each other)

• 2) Forced Draught Counterflow (fan at the side pushes air through tower and out the top - air and water oppose each other)

• 3) Induced Draught Crossflow (fan at the top pulls air through the tower and out at the other side)

• 4) Forced Draught Crossflow (fan at the side pushes the air through the tower and out at the other side)

• Continuous operation (7 days)

• Timed operation (week days)

• Seasonal operation

• Intermittent operation

DUTY HOLDER

• Is the 'Duty Holder' identified in writing?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Who is the Duty Holder:

RESPONSIBLE PERSON

• Has a ‘Responsible Person’ been appointed to be managerially responsible for the legionella management of the cooling tower and identified in writing?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Who is the 'Responsible Person'?

• Has the Responsible Person received appropriate training on their role?

  Yes

  No

  Improvement required

  N/A or Not discussed

• City and Guild accredited 'Legionella Responsible Person - Cooling systems' recognised by LCA

OPERATIONAL RESPONSIBLE PERSON

• Has an 'Operational Responsible Person' been appointed and identified in writing to implement the water management plan for the control of legionella?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Who is the 'Operational Responsible Person'?

• Has the Operational Responsible Person received appropriate training on their role?

  Yes

  No

  Improvement required

  N/A or Not discussed

• City and Guild accredited 'Legionella Responsible Person - Cooling systems' recognised by LCA

APPOINTED PERSONS

• Have 'Appointed Persons' been identified to undertake relevant day to day aspects of the water management plan relating to the cooling tower?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Who are the Appointed Persons in relation to overseeing the Cooling Tower?

• Have Appointed Persons received appropriate training on their role and responsibility for the cooling tower?

  Yes

  No

  Improvement required

  N/A or Not discussed

• City and Guild accredited 'Legionella Responsible Person - Cooling systems' recognised by LCA

COMPETENT PERSONS

• Have one or more 'Competent Persons' been appointed to undertake water treatment, maintenance and assessment of the Cooling Tower?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Who are the 'Competent Persons'?

• Are the risk assessors of the Cooling Tower members of the Legionella Control Associations' Code of Conduct or UKAS's accreditation for legionella assessment?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are the roles and responsibilities of the external contractors clearly defined in writing?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is there evidence that the Operational Responsible Person has completed a Cooling Tower notification form and forwarded it to the Head of Environment and Regulatory Services?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is the last notification still relevant to the plant in place (i.e. no subsequent decommisioning)?

  Yes

  No

  Improvement required

  N/A or Not discussed

Assessment

• Has a risk assessment been completed for the prevention and control of Legionella bacteria associated with the Cooling Tower?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Was the assessment carried out in compliance with BS8580-1 Water Quality - Risk assessments for Legionella Control?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is a copy of the Legionella Risk Assessment kept electronically on the asset management system (Atrium)?

  Yes

  No

  Improvement required

  N/A or Not discussed

REVIEW AND RE-ASSESSMENT

• Are arrangements in place to ensure the legionella risk assessment for the cooling tower is subject to periodic 'Review' (e.g. following changes to water system, results of checks, system modifications and changes to personnel etc) to ensure it remains up-to-date?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the person completing the review possess suitable skills, knowledge and experience to undertake the review?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the review determine whether the system requires 're-assessing'?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Date of review/re-assessment detailed on the risk assessment

  Date

• Has the assessment been re-viewed and where necessary reassessed in accordance with the assessors recommendation/internal arrangements?

  Yes

  No

  Improvement required

  N/A or Not discussed

• What is the current risk categorisation for the Cooling Tower?

• Has elimination or replacement with a lower risk system been considered?

  Yes

  No

  Improvement required

  N/A or Not discussed

ACTIONS

• Are the actions arising from the assessment tracked and monitored internally by the team responsible?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is there evidence that any high and medium risks have been addressed within timescale?

  Yes

  No

  Improvement required

  N/A or Not discussed

WRITTEN SCHEME

• Is there a written scheme for controlling the risk from exposure to legionella bacteria from the Cooling Tower? (if the assessment has shown there is a reasonable foreseeable risk of exposure to legionella bacteria there must be a written scheme)

  Yes

  No

  Improvement required

  N/A or Not discussed

• Has the written scheme been subject to regular review?

  Yes

  No

  Improvement required

  N/A or Not discussed

SCHEMATIC PLAN

• Does the written scheme contain an up-to-date schematic plan showing the layout of the water system?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the plan show the required elements?

  Yes

  No

  Improvement required

  N/A or Not discussed

• All cooling towers

• All system control valves

• All standby equipment eg spare pumps

• The location of system bleed valves

• All associated storage tanks

• The location of chemical dosing points and/or injection points

• The location of the system drain valves

• The origin of the water supply

OPERATIONS MANUAL

• Does the manual contain a description of the SAFE AND CORRECT OPERATION OF THE SYSTEM to control the risk of exposure to legionella bacteria?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the manual contain details of the PRECAUTIONS TO BE TAKEN INCLUDING ANY WATER TREATMENT PROGRAMME?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the manual contain details of the CHECKS REQUIRED TO ENSURE THE EFFECTIVENESS OF THE SCHEME AND THEIR FREQUENCY (daily, monthly, quarterly) ?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does the manual contain details of the REMEDIAL ACTIONS TO BE TAKEN IN THE EVENT OF THE SCHEME BEING SHOWN NOT TO BE EFFECTIVE?

  Yes

  No

  Improvement required

  N/A or Not discussed

OPERATING LIMITS FOR PARAMETERS BEING MEASURED IN THE TOWER

• Are the safe operating limits for each parameter which is being measured specified for each tower?

  Yes

  No

  Improvement required

  N/A or Not discussed
Tower

• pH (scale, corrosion, biocides)

• Total Ca Hardness (scale) <0.95

• Conductivity (bleed)

• Corrosion Inhibitor

• Suspended Solids (absent in incoming water)

• Concentration Factor

• Br (0.5 - 1.0)

• Cl (0.5 - 1.0)

• Is there a hard copy logbook located on site or an accessible electronic record held containing relevant information?

  Yes

  No

  Improvement required

  N/A or Not discussed

• A log to be signed by all contractors carrying out work on the cooling tower water systems and description of the work

• A register for weekly/monthly testing and maintenance in accordance with the written scheme

• Are records of monitoring and inspection retained for a minimum of 5 years?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is the chemical composition of the cooling and make up water monitored monthly with records available?

  Yes

  No

  Improvement required

  N/A or Not discussed

DISOLVED SOLIDS (eg calcium carbonate when heated forms SCALE (scale protects the bacteria and reduces effectiveness of biocide)

• Are controls in place to address SCALE?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is water softened/blended (to remove Ca and convert to Na)

  Yes

  No

• Is the water softener tested daily and the salt supply checked?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is a scale inhibitor used (to keep Ca in dissolved form)

  Yes

  No

• Is scale inhibitor continuously added via a dosing pump controlled by water pump?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Acid dosing (to lower the pH and alkalinity)

  Yes

  No

• Bleed off and Concentration Factor (limits the cycles of concentration)

  Yes

  No

• Are SCALE levels being measured via conductivity/alkalinity?

  Yes

  No

  Improvement required

  N/A or Not discussed

• What is the conductivity target?

• Over the last 4 weeks have the weekly conductivity readings (TDS) been within specified limits?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Via Bleed off and Concentration Factor

  Yes

  No

SUSPENDED SOLIDS (eg dust and algae lead to FOULING that provides biological nutrients and protection to legionella)

• Are controls in place to address FOULING?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Oxidising biocide application (Cl for large towers; Br for smaller cooling systems where pH is over 8; Cl dioxide - dosing issues)

  Yes

  No

• Automatic (feedback eg Redox sensor)

• Automatic (proportionally dosed in relation to bleed, make up water)

• Automatic (Timed)

• Manual (consider H&S risks of application)

• Are automatic pumps calibrated regularly

• Dispersants (keep suspended solids in suspension)

  Yes

  No

• Non-oxidising biocide (slower action)

  Yes

  No

• Ozone

  Yes

  No

• UV (usually in conjunction with a biocide)

  Yes

  No

• Filtration (side stream - filters a % of circulating water)

  Yes

  No

• Bleed off and control of Concentration Factor (release of suspended solids)

  Yes

  No

• What should the biocide Level be? (650 = good sanitising ability, 450 = not enough)

• Is FOULING being measured (effectiveness of biocide regime)?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Biocide regime monitored weekly via on-site microbial dip slides (legionella bacteria will not grow but other bacteria will)

  Yes

  No

• What is the target ACC @ 30C (dip slide count) for each tower?

• Is there an incubator on site and evidence of periodic service?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are satisfactory dip slide trends evident over the last 4 weeks in each tower?

  Yes

  No

• Has appropriate action been taken in response to elevated dip slide readings (10,000 or less = system under control; 10,000 to 100,000 = review controls and resample; 100,000 + = re-sample, shot dose with appropriate biocide)

  Yes

  No

  Improvement required

  N/A or Not discussed

• Clarity

  Yes

  No

• Control of Concentration Factor via Bleed Off

  Yes

  No

GASES (eg Oxygen cause CORROSION (pitting) that destroys plant and releases nutrients i.e. Fe for bacteria.

• Is the tower made of a material that is more resistant to corrosion (stainless steel or copper) rather than a material more susceptible to corrosion (Mild steel)?

  Yes

  No

• Are controls in place to address CORRISION of the plant?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Corrosion Inhibitor added (forms barrier to cover metal)

• Is CORROSION being measured?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Oxygen meter

• Control of Concentration Factor

• Is the importance of Bleed Off (i.e. release of make up water and its replacement with fresh water to stop Calcium carbonate coming out of suspension (scale) and Suspended Solids building up) in maintaining the desired Concentration Factor (No. of times solids build in the system water) understood?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is Bleed Off suitably controlled?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Conductivity

• Proportional to use

• Continuous

• Timer

• Manual

• Is a target Concentration Factor stated in the written scheme?

  Yes

  No

  Improvement required

  N/A or Not discussed

• What is the stated target monthly Concentration Factor (Optimum 2.5 to 5.5; lower is safe but water and chemical costs high)?

• What was the last recorded Conductivity reading of the System water (A)?

• What was the last recorded Conductivity reading of the Make-up water (B)?

• What is the Concentration Factor (A / B = CF)

• Is the target CF being achieved?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are samples for legionella taken quarterly?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are Legionella results in the last 12 months satisfactory?

  Yes

  No

  Improvement required

  N/A or Not discussed

• <100 cfu/l = ok

• 100 to 1000 cfu/l = low level legionella count which could be sporadic - Review water treatment system and adjust biocide dosage and resample.

• +1000 cfu/l = Immediate action - Shot dose with biocide or increase the level of continuous dosage. Review water treatment programme and resample within 48hrs. If still high review risk assessment to identify remedial actions.

• Has analysis of water samples for legionella been performed in UKAS accredited laboratories with the current ISO standard methods for the detection and enumeration of legionella included within the scope of accreditation?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Has the correct action been taken following sampling results?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is there a written procedure for regular cleaning and disinfection of the system?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Does cleaning and disinfection take place: a) at least every 6 months (if free from fouling), b) if shut down for a month or more, or c) following alterations to system?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Date of last clean and disinfection certificate/job sheet

  Date

• If packs are present and cannot be removed (evaporative condenser), are there alternative methods for making sure they remain clean?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Where the cooling tower system operates continuously and it is only possible for the system to be completely shut down infrequently are suitable alternative arrangements in place?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Continuous auto dosing of oxidising biocide

• Maintaining the correct pH level when using oxidising biocides

• Dosage of additional dispersants

• Side stream filtration

• More frequent microbial monitoring (Monthly legionella)

• Partial system shutdowns

• Ensure towers switched off and left to settle for 30 minutes and fans isolated

Tower

• Is the physical condition of the system checked weekly and records held?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are records complete?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is there evidence of actions being addressed in a timely manners?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Do fans have a cage?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are air intakes a suitable distance away from the towers?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is the outer structure clean?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Absence of leaks around hatches and seals/joints?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Are Drift eliminators suitable and maintained?

  Yes

  No

  Improvement required

  N/A or Not discussed

• No damage

• Not ill fitting

• Mist only - no droplets

• Eliminate sunlight

• Not wooden slats

• Are nozzles in good order?

  Yes

  No

  Improvement required

  N/A or Not discussed

• No scale

• Good distribution

• For Cooling Towers, is the fill pack in good order?

  Yes

  No

  Improvement required

  N/A or Not discussed

• In place

• Well ordered

• No scale

• Does water flow evenly across the fill pack?

  Yes

  No

  Improvement required

  N/A or Not discussed

• For Evaporative Condensers, is the condensing coil in good order?

  Yes

  No

  Improvement required

  N/A or Not discussed

• In Place

• No scale

• Are dosing pumps/lines in good order?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Functioning/no leaks

• Is the Pond in good order?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Water clean

• No sludge/sediment

• Fully enclosed to prevent direct sunlight onto the water

• Are visible surfaces free from slime, scale and corrosion (pitting)?

  Yes

  No

  Improvement required

  N/A or Not discussed

• Is the Conductivity probe accessible and removable for recalibration?

  Yes

  No

  Improvement required

  N/A or Not discussed