SMOKE AND FIRE DAMPERS IN HVAC SYSTEMS MAINTENANCE AND MANAGEMENT

Transcription

1 SMOKE AND FIRE DAMPERS IN HVAC SYSTEMS MAINTENANCE AND MANAGEMENT maintaining safe environments

2 Introduction HVAC ductwork is a necessity of modern building design a way of passing air between rooms and building zones and keeping the building and its occupants healthy and comfortable. But when a fire breaks out, that very ductwork becomes a potential hazard; there s no point having fire doors or fireresistant construction zones if there are deliberate channels provided for smoke, hot air and flames to pass through. In such a situation there s a danger the ducting system will become a distribution system spreading hazardous smoke throughout a building and undermining all efforts to confine it and quickly deal with the cause of the blaze. That s where dampers come in. A requirement under the government s Approved Document B, dampers are louvred vents or shutters situated at key points within the ducting system. In normal, everyday conditions they are inert, simply allowing the flow of air through them and not interfering in the system at all. But if a fire starts, they come into their own. They slam shut, blocking the duct and preventing smoke from passing through for a period of up to hours in theory more than enough time to facilitate occupant escape and fire fighter entry. The catch, unfortunately, is that after buildings are constructed or altered, it s often the case that few records are kept of where these dampers are installed. And with poor records comes poor maintenance

3 Case study 1 Damper servicing at one of the NHS largest teaching trusts The John Radcliffe Hospital is Oxfordshire s main accident and emergency site, providing acute medical and surgical services including trauma, intensive care and cardiothoracic services. It is the largest of the Trust s hospitals, covering around 66 acres, and includes: Children s Hospital Eye Hospital Heart Centre West Wing Women s Centre The John Radcliffe site also houses many departments of Oxford University Medical School, is home to the George Pickering Education Centre and is a base for most medical students who are trained throughout the Trust. Across its facilities there are thousands of dampers all in need of surveying and servicing. In a hospital environment like this there are two main concerns the first is patient and staff safety, hence Brakel Airvent being appointed to undertake damper survey and maintenance works as a company with the experience and capacity to manage a project of this scale. The other consideration is disruption. John Radcliffe exists to save people s lives and anything that interferes with that process is a serious hazard. Therefore Brakel Airvent was careful to ensure all survey works were undertaken in the least disruptive manner possible and that all maintenance in key areas was done out-of-hours. In this way we were able to provide the client with a detailed breakdown of their damper status and ensure that all relevant regulations were being adhered to in the name of fire and smoke safety. Difference between smoke and fire dampers Ostensibly, smoke and fire dampers fill incredibly similar roles. They re put in similar locations and they re both designed to stop ducting becoming a weak point in a building s fire safety arrangements. But there are differences, and they boil down to where the damper is situated: Fire damper These are located in ductwork at the intersection of fire-rated barriers in building zones, like walls or partitions. The damper secures the integrity of the barrier preventing fire penetration before temperatures reach the fire rating level of the barrier itself. Smoke damper These work in a similar manner to preserve the integrity of smoke barriers (e.g. floors, walls or smokeresistant ceilings) without the same stringent temperature restrictions. They are often located in sensitive areas where smoke penetration would present particular challenges and must be installed with proper seals to prevent smoke leakage. While operation systems can be interchangeable, it s more common for smoke dampers to be motorised and connected to a control panel. This means smoke detectors and controls are responsible for activating the damper and it makes testing for maintenance purposes much easier. Fire dampers would more usually be fitted with mechanical or fusible linkages, which operate under high temperatures and cause the louvres or shutters to shut firm. This method may be considered more failsafe as it s the action of the fire itself that activates the damper, but it means that by the time the damper activates, there may already have been significant passage of smoke (which travels so much faster than flames). Also note that there are hybrid dampers available, which fulfil the roles of both smoke and fire dampers.

4 Case study 2 Smoke and Fire Dampers at Great Western Hospital Overlooking damper maintenance simply builds up trouble for the future. Brakel Airvent s relentless campaigning to raise awareness of the RRO and the need for proper maintenance of fire safety equipment in ensuring safety and legislative compliance really seems to be paying off. One organisation to be in touch regarding a system of fire and smoke dampers that was particularly difficult to manage due to ongoing building developments and refurbishments is the health authority governing the large Great Western Hospital in Swindon. Brakel Airvent was appointed to review the site, looking for dampers within ductwork beyond false ceilings and within vertical risers, to create asset lists and maintenance plans. Working with Chubb Mechanical, Brakel Airvent approached the site with particular caution; it was vitally important that medical activities at the hospital were not interfered with during works, necessitating careful work scheduling and flexible working practises. By combining years of experience in damper service and maintenance with a reputation for considerate working practises that defines Brakel Airvent s engineers hands-on approach, the wide-ranging project was completed in line with budget and schedule expectations, with minimal disruption to patient care. It s always important that maintenance staff don t cause disruption on site, but never more so than at a hospital site where lives literally hang in the balance.

5 The big problem So, we ve established that smoke and fire dampers are invaluable when it comes to maintaining the integrity of any building s fire strategy. So, what s the problem? The thing is that dampers generally work fine when they re first installed. But often the details of these installations aren t properly recorded and building owners are left without a clear idea of exactly how many dampers are in their building or where exactly they can be found. It might sound like a crazy idea but we have vast experience of encountering this exact situation. And, naturally, if the damper situation is vague, the maintenance history gets really vague. Dampers, like any piece of life safety equipment, need love and care to make sure they re able to function in the way that s expected of them. This situation is heighted by the fact that unlike something like a fire alarm or smoke curtain dampers are generally not on display and are frequently incredibly difficult to physically access (seriously, contractors, please consider maintenance when you re installing this stuff!). Here s a worst-case scenario that we ve bumped up against more times than we care to disclose: The building owner or facilities manager knows they have a HVAC system and that the RRO (Regulatory Reform (Fire Safety) Order 2005) and BS5588 requires them to undertake maintenance work. They don t know how many dampers they have on site. They don t know where their dampers are located. They don t know the service specifications of their dampers, or even whether they re motorised or fusible link. They don t have a clear record of when their dampers were last tested, serviced or replaced. There may have been structural changes to the building over a period of years, further muddying the waters in the find the damper game they re forced to play. Sounds awful, doesn t it? And again let us remind you that these mystery dampers NEED to be installed correctly and in full working order. There s simply no room for messing around here.

6 Case study 3 Patient safety in Bristol s South Meads Hospital Thousands of dampers in one site this hospital needed a plan. The South Meads hospital is a centre of excellence for health care in the South West region across a number of specialist fields, as well as being linked to one of the largest hospital trusts in the UK. South Meads is new hospital whose smoke control systems are just out of warranty. The client got in touch as they were rightly so keen to make sure all relevant maintenance standards were met and, if possible, exceeded. In this quest for wanting to ensure the highest of safety standards, the client worked closely with Brakel Airvent to develop what must be the industry s most comprehensive traceable data file of damper systems. It s a significant survey to confirm assets and update information, service and data gathering and allow management for legacy purposes. Our work included full site surveying to ensure all equipment was properly listed and serviced, in addition to the hands-on maintenance that we re renowned for in this case over 2000 dampers brought up to the most recent regulations and recommendations. Each damper was given an individual report including status, details of tests completed, remedial works required and photographic information to support. The work that was carried out had a range of access requirements with both normal and out-of-hours working to suit the use of an active hospital. Due to quality of work done and a strong relationship with our FM client we have now also been awarded the service contact for over 100 smoke curtains and other systems will be reviewed when required. Damper regulations Successful damper maintenance and management requires a good deal of legislative understanding The Regulatory Reform (Fire Safety) Order 2005 BS 9999 : 2017; Code of practice for fire safety in the design, management and use of buildings The Fire (Scotland) Act BRE 368(1999) Fire Safety Act 1987 BS En ; Fire resistance tests for service installations, Fire Dampers BS ISO & 2; Fire-resistance tests; Fire dampers for air distribution systems Fire Precautions (Workplace) Regulations 1997 Fire Precautions (Health & Safety) Regulations 1999 EN H & S Reg 6 Para 33 Mechanical Ventilation Systems BS 5588: 1998 All parts for Smoke Ventilation Systems BS 5588: 1998 Part 4 section 12 inspection and Maintenance IRATA Access Works H & S Regulation 6 Maintenance and Testing H & S and IEE Regulations servicing and high level access works

7 What s the answer? When you re presented with the kind of challenge outlined in this document, you obviously realise that maintenance is the key. Proper, preventative, pre-emptive service work undertaken by qualified specialists will save time, money, hassle and most importantly lives. But that s only part of the answer. There s no point in getting your dampers serviced and then forgetting about them for the next few years until you re in the same position again. At Brakel Airvent we believe the solution is one of management as much as maintenance. And that means record keeping and proper data management. We would highly recommend locating a damper maintenance provider that is able to: Review and advise Step 1 is to look over your damper maintenance provision, review your processes and offer advice on how best to proceed. Survey and plan Next comes a survey of your site, verifying damper locations (or helping to locate unknown dampers), giving a clear picture of the scale of the operation and an idea of the existing maintenance schedule. Service and report Checking out each damper individually reveals the operational status of the system, and you ll also need to ensure their combined effectiveness with a review of the controls in place on-site. Repair and replace Damper maintenance is a vital part of keeping a building safe from smoke and fire. We wouldn t recommend ripping out products en masse; instead choose the most costeffective and considerate way forward. Create a database The hub of a successful damper review process a proper file that contains the location, specs and maintenance history of all your dampers will make the process easier and cheaper going forward and is a vital step in keeping your building safe. Conclusions The big thing to remember is this smoke and fire dampers serve the same purpose as any smoke control equipment: they facilitate the escape of building occupants and allow easier fire fighter access. Which is to say, they save lives and protect property. That means their maintenance is of the utmost importance. Within the BRE report Examination of the Fire Resistance Requirements for Ducts and Dampers, produced on behalf of the ODPM, there are numerous case studies from both the UK and USA of fires within ducted HVAC systems. Regular routine specialist preventative maintenance and testing is the solution, and proper data collection is the way to manage this solution. Over the past 30 years Brakel Airvent has built up an unmatched and unique expertise in providing service and technical support to all types of active smoke control and ventilation equipment. We have a dedicated team of damper specialists and are happy to deal with any enquiries you may have just call

8 We got it covered Our regional engineering, sales and operations centres provide local customer support from the UK s largest and best-trained team of technical service/refurbishment engineers. Dedicated H&S, design and projects teams ensure compliance with the latest legislation and our work is carried out to the highest standards, when agreed and on budget. Factor in our UK-wide network of approved partners and the resources of the Brakel Group and we are proud to offer our clients the UK s leading range of smoke control and air quality solutions. Designed and printed by horizondml.co.uk HQ, Operations and Admin Centre: Unit 7, Mellyn Mair Business Centre, Lamby Industrial Park, Wentloog Avenue, Cardiff, CF3 2EX Tel: Northern Operations and Engineering Centre: Suite G1, North East of England Business Centre, Wearfield Enterprise Park, Sunderland, SR5 2TA Tel: Approved Contractor customer.services@airvent.co.uk