Conflict Resolution Related to Legionella Infection - Assignment Example

University of Central Lancashire School of Engineering FV2102 Assignment Brief Question 1: Explain with reference to relevant case law the statutory responsibility placed on Acme Hydrocarbons Ltd and the Contractor Flow Systems Ltd with respect to ‘Item 1’ of the HSE Letter (Document 2) Answer Under the Health and Safety at Work Act 1974, Acme Hydrocarbons Ltd management is required to consider all the risks at their work place such as legionella bacteria that may arise from their industrial activities, and all its premises that is connected with the company. These legal duties are outlined in the L8 ACOP document, Legionnaires ‘disease (Nguyen, Stout, and Yu, 2006). This Act also extends the control of Legionella bacteria which requires organisations to assess the risk of legionella bacteria that may affect not just the employees (Muraca, Stout and Yu, 2003), but also visitors and members of the public, therefore the company should take necessary precautions to minimise all the risks that are associated with Legionnaire disease. It is mandatory to carry Legionella risk assessment on companies that largely involves water in there manufacturing process. Legionella risk assessment is a legal requirement under Control of Substances Hazardous to Health (COSHH), Regulations 2002the Health and Safety at Work Act 1974, and lastly under the management of Health and Safety at Work Regulations Act 1999. Therefore the company is required to conduct legionella risk assessment in its premises (Katz and Hammel, 2009). These laws have been integrated in the Approved Code of Practice and guidance (ACPG) document, “Legionnaires’ disease: The control of Legionella bacteria in water systems” (Katz and Hammel, 2009). It is the responsibility of the Hydrocarbons Ltd management to make sure that risk assessment has been conducted at their premises in order assess and identify risk exposure to Legionella microrganism from its cooling tower and it related work activities and to put in place necessary measures that will enable the company to mitigate risks. Hydrocarbons Ltd can appoint or contract a peson to take charge of day-to-day responsibility/care of idenfitying and controlling risks that may eminate from Legionella bacteria (Dennis and Lee, 2004). COSHH Regulations 2002 gives recommendations for how a contractor can carry out a risk assessment (Dennis and Lee, 2004). An outsider that is conducting the risk assessment must have an understanding and knowledge of the requirements and process of the COSHH 2002 regulations. Employer notification is important to enable the authority to identify the premise, plan its risk assessment and inspect activities in accordance with regulation 22 and 25 of COSHH and ensure that the company does comply with his duties under these regulations. Similarly, under Regulation 6 of COSHH Regulations 2002 requires Hydrocarbons Ltd not to carry out work liable that exposes its staff and non-staff for instance vistors and members of the public to hazardous substances without carrying out a risk assessment to their premises and implementing required measures that comply to with the CSHH regulations (Broadbent, 2000). Any risk that is associated with the hazardous material or substances that is present in the workplace should be assessed (Nguyen, Stout, and Yu, 2006). And the sole responsibility for the risk assessment lies with the employer. If the outside help is required, they may call for outside assistance. Under the Notification of Cooling Towers and Evaporative Condensers (NCTEC) Regulations 1992, Hydrocarbons Ltd should have notified the local authority in writing about its evaporative condenser or cooling tower on site, and the company should have included details about its location. System that don’t rely on the principle of evaporations ( such as dry and wet coolers or condensers) are the ones that cannot be reported under NCTEC Regulations 1992 (Dennis and Lee, 2004), but Hydrocarbons Ltd are required to assess these system against requirements that are defined in NCTEC Regulations. For example, if cooling tower spray water droplets onto the surface of the cooling tower. In addition, under RIDDOR Regulations, it is the duty of Hydrocarbons Ltd to report any cases of legionellosis disease in employees or contracted persons who have worked on cooling towers (Muraca, Stout and Yu, 2003). Question 2: Critically analyse the data provided in ‘Document 3’ and with reference to other information provided and researched, draw conclusions to the current risk of exposure to legonnela bacteria. Answers In aqueous water environments, temperature has been found to play a crucial role in Legionella bacteria grouwth (Muraca, Stout and Yu, 2003). According to the Legionella risk assessment, the temperature in the cooling plant range 4-18 ºC, this is an optimal temperature for Legionella bacteria multiplication (Muraca, Stout and Yu, 2003). Legionella bacteria grown best at temperature between 20°C to 45°C with optimum temperature growth range 35°C to 40°C; but higher temperature has been found to kill Legionella bacteria (Dennis and Lee, 2004). It has been found that Legionella bacteria can survive and multiply itself under 2 log drops over a period of 30 days in water (Katz and Hammel, 2009). However, higher pH values reduced Legionella bacterial survival (Mauchline et el, 2005). However, it should be known that cooling towers that have higher pH values create good conditions for legionellae bacteria to thrive (Katz and Hammel, 2009). The use of biocides to treat water in the cooling system has been found to last at the most only a few months (Muraca, Stout and Yu, 2003). Therefore, during treatment of water, biocide should be used in the maintenance if their efficiency is too low or technical improvements cannot be conducted. According to the Legionella risk assessment report, between 5/5/11 to 12/5/11 there was a maintenance lapse in the cooling tower where the company ran out of biocide which left the cooling system vulnerable to Legionella bacteria. It should be noted that the effect of biocides only last a few days or weeks if simultaneous technical maintenance have not been carried out (Dennis and Lee, 2004). Because of the effect of humidity that was present around the cooling tower, legionella bacteria have been found that their survival was improved when humidity is increased. Such a finding has been confirmed by Berendt (2006), who stated there is a positive relationship between cases of Legionnaires ’ disease and increasing humidity. The cooling tower contains water which exceed 20 0C and which release aerosol or spray when being maintained or during operation also present a risk. The presence of green algae on the reservoir is a major problem in the cooling tower. Algae can deposit around the cooling tower and in high ambient room temperatures, the cooling tower is an ideal growth medium for Legionella bacteria (Nguyen, Stout, and Yu, 2006). Algae can trap legionella bacteria, and this will provide a perfect growth medium that biocides cannot penetrate (Berendt, 2006). The green algae that Legionella bacteria colonize can continuously re-contaminate the cooling tower, even after disinfection (Dennis and Lee, 2004). In addition, the green algae present in the cooling tower are a source of nutrients for legionella bacteria. Lastly, the pipe tripping that occurred on 26/5/11 provide perfect environment for Legionella that may be able to colonize in certain types of pipework (Berendt, 2006), water fitting and materials such as steel used in the construction of cooling tower. In addition, pump tripping has allowed water to be stagnant and this provides the best breeding ground for the growth of Legionella bacteria. Questions 3: Draft a reply to the HSE Inspectors letter (including an outline plan of actions the company intends to take) that is likely to convince the Inspector that no further enforcement is necessary. Answer Dear Mr. Patrick Smith, Re legionella bacteria risk mitigation procedure. In reference to Legionella risk assessment you conducted at Acme Hydrocarbons Ltd on 28th May 2011. This company is now aware that water system can create conditions that promote growth of the legionella bateria. Therefore, the company has put up control measures that will prevent or reduce legionella bacteria amplification in its water system. The control measures are as follows: Inspection and Maintenance. Visual inspection of the cooling tower system and its maintenance will be carried out regularly in order to control and minimise growth of of Legionella bacteria and other micro-organisms. The cooling tower and its piping will regularly monitored and maintenance will be done regularly to prevent bio fouling build-up in cooling tower pipes, sediment and scales that encourages Legionella bacteria growth. Use of biocide. Periodically biocides will be used in cooling towers to in order to control legionella bacteria from multiplying in the cooling tower water system. Cleaning. Frequent clening of cooling towers will be done and disinfection will be done at least thrice per year. This routine management and maintenace will be done regularly before start-up and after shut down of the cooling tower. COSHH. Acceptable cleaning standards that have been indicated in the COSHH Regulations 2002 will be used. Elimination. Cooling towers will be covered to prevent contamination and storage time for water in the cooling tower will be reduced to a day or less. This will prevent of stagnation of water which promotes growth of legionella bacteria. Recordkeeping. A description of the operating system of the cooling tower will be maintained. In addition, Log books will be used to list water-quality test results, date of inspections, and maintenance of cooling towers. Protection. Any employees assign to work with cooling towers will be required to wear protection gear. Kindly you can review these measures and let me know if there are other measures that can be used to prevent Legionella bacteria. Thanks in advance. Many Regards Plant. . Reference List Best, M., A. Goetz, and V.L. Yu. "Heat eradication measures for control of nosocomial Legionnaires' disease." American Journal of Infection Control, 12, (1), 1984, pp. 26- 30. Berendt R. F 2006, Survival of Legionella pneumophila in aerosols: effect of relative humidity The Journal of Infectious Diseases 141, pp.689 Broadbent, C.R 2000, "Legionella in Cooling Towers: Practical Research, Design, Treatment and Control Guidelines." Delivered at 2000 Inter. Symp. on Legionella, Amer. Society for Micro., Jan. 26-29, 2000, Orlando Fl. Dennis P. J. D. & Lee J. V 2004, Differences in aerosol survival between pathogenic and non-pathogenic strains of Legionella pneumophila serogroup 1 Journal of Applied Bacteriology 65, pp.135 - 141 Katz S. M. and Hammel J. M. 2009, The effect of drying, heat and pH on the survival of Legionella pneumophila Annals of Clinical and Laboratory Science 17, pp.150 - 156 Mauchline W. S., James B. W., Fitzgeorge R. B., Dennis P. J. and Keevil C. W 2005, Growth temperature reversibly modulates the virulence of Legionella pneumophila Infection and Immunity 62, pp.2995 - 2997 Muraca P., Stout J. E and Yu V. L. 2003, Comparative assessment of chlorine, heat, ozone, and UV light for killing Legionella pneumophila within a model plumbing system Applied and Environmental microbiology 53, pp.447 – 453 Nguyen, M.H., J.E. Stout, and V.L. Yu September 2006, "Legionellosis." Lower Respiratory Tract Infections, 5, (3), pp. 561-584. Read More