New starts slump 35pc year-on-year up to April 2009

10/06/2009 by David Slade.

New construction projects starting on site fell by over a third for the three month leading up to April 2009 compared with the same period a year earlier, according to the latest figures from business intelligence firm Glenigan.

New project starts fall 35 per cent on a year ago with non-residential and housing project starts being the worse hit, falling by 39 per cent and 52 per cent respectively.

Across the country the picture was fairly bleak with the north of England experiencing some of the sharpest falls in the value of project starts last year, the Midlands, the east of England, London and the South-east experienced the largest declines during the first quarter.

The decline in residential project starts has been driven by private housing and prospects are forecast to deteriorate over the next two quarters as house builders focus on selling stock and reducing work in progress in the face of worsening UK economic conditions, falling house prices and limited mortgage availability.

However, there is some encouraging news for certain sectors with civil engineering experiencing a rise of 20 per cent in the beginning of 2009 with several road and energy projects starting on site during the first quarter.

The forecast for sector remains positive for the rest of the year, driven by new renewable energy projects and spending on rail and road infrastructure.

Glenigan economics director Allan Wilén said:“Residential construction projects are expected to deteriorate further over the next two quarters, prospects for non-residential projects are mixed and the outlook for civil engineering is expected to be positive throughout 2009.”

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Construction output to drop 7.5pc in 2009

10/06/2009 by David Slade.

Construction output in the UK is projected to fall by 7.5 per cent this year after a decline of 0.2 per cent in 2008, according to the latest forecasts from Experian.

The UK is only predicted to return to modest growth of 1.6 per cent in 2011.

The figures released by Euroconstruct at its Warsaw conference, predict construction output across the 19 countries in the Euroconstruct network to fall by 7.5 per cent this year after a decline of 3 per cent last year.

James Hastings, head of construction futures at Experian,said: “While countries such as Germany were not nearly so exposed to ‘toxic’ debt as the UK, their export-led growth has been badly hit by the decline in world trade, with a consequent knock-on effect on construction activity.”

The decline in activity is predicted to be in double digits in Finland, Ireland, Portugal and Spain, mainly due to the weakness of the housing market in all four countries.

In France, Germany, Italy, and the UK the decline is expected to be more moderate than in Spain, ranging from -3.5 per cent in Germany to -7.5 per cent in Italy and the UK.

Only Switzerland and Poland are forecast to see any increase in activity this year, both driven by civil engineering work and a stable level of activity in the residential sector.

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Cisco Systems Partners with Duke Energy to Develop & Implement Smart Grid Technology

10/06/2009 by David Slade.

CHARLOTTE, N.C. -Duke Energy announced it will join forces with Cisco Systems Inc., the world’s largest network communications company, to fast-track development of Duke Energy’s state-of-the-art electric “smart grid.” The two companies will jointly evaluate a variety of smart grid communications hardware and software, and oversee installation and testing of selected equipment and software throughout Duke Energy’s electric grid.In addition, Cisco will work with Duke Energy to develop and install home energy management devices to help customers control and reduce their electricity consumption.

Todd Arnold, senior vice president for smart grid and customer systems at Duke Energy, America’s third-largest electric utility.

“Our goal is to rapidly transform the way electricity is delivered to, and used by, the 11 million people we serve in five states.Partnering with Cisco is central to Duke Energy’s plan to build an ‘energy internet’ that will improve electricity delivery, strengthen grid security, lessen our company’s environmental impact, and help customers reduce their electricity usage.”

The three-year partnership is the latest development in Duke Energy’s effort to rapidly convert its existing electricity delivery infrastructure into an advanced smart grid that uses two-way digital communication to reduce energy usage, improve efficiency, bolster system reliability, detect power outages, and integrate solar and other renewable energy sources into the electric grid.

Cisco Systems, working closely with Duke Energy, will develop a highly refined, end-to-end, smart grid communications architecture - one that both companies believe will be among the most comprehensive and interoperable in the electric utility industry.

The newly created architecture will be based on what the industry calls “internet protocol-based open standards” - an approach that permits easy accommodation of new and emerging communications technology as it becomes available in future years.

Marthin De Beer, senior vice president and general manager ofCisco’s Emerging Technologies Group;

“Internet protocol-based open standards are key to creating a smart, highly-secure backbone for the nation’s modern electrical grid. The two companies also will test a new generation of durable, weather-proof communications equipment designed for use at Duke Energy’s electric substations.”

Replacing our analog electric grid with advanced digital technology to create a 21st century electricity delivery system largely involves data, networks and communications - all of it Cisco’s expertise,” Arnold said.

In Ohio, Duke Energy later this year will launch a five-year mass deployment of smart grid technology, including more than 700,000 electric smart meters and 450,000 natural gas smart meters.

In Indiana, Duke Energy is seeking approval from the Indiana Utility Regulatory Commission to install extensive smart grid technology, including approximately 800,000 smart meters.

Duke Energy announced it had reached a settlement agreement with the Indiana Office of Utility Consumer Counselor and key consumer and business groups regarding the company’s Indiana smart grid proposal.

In addition to smart meters, Duke Energy plans to install a large amount of distribution automation - both hardware and software - to improve system efficiency and reliability on its electric grid in both Indiana and Ohio.

The company also is laying the groundwork to bring large-scale smart grid technology to three other states it serves - North Carolina, South Carolina and Kentucky.

“Working with innovative industry leaders like Duke Energy, Cisco will deliver an end-to-end network infrastructure from power plant to customer in order to manage electricity supply and consumption both efficiently and in an environmentally responsible manner,” said Cisco’s De Beer.

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What is DALI ?

10/06/2009 by David Slade.

DALI stands for Digital Addressable Lighting Interface and is a protocol set out in the technical standard IEC 60929.

DALI is a bi-directional, digital protocol developed by lighting manufacturers for the control of light source levels. The initial application is for control of fluorescent lamps, both linear and compact to be followed by control of additional light sources such as HID, LED, incandescent, etc.

The DALI protocol has been added to IEC60929, and will be incorporated into an ANSI C82 standard. In addition, both IEC and ANSI are working on extending the DALI system to include other products such as occupant sensors and daylight sensors,

Using DALI, a digital standard in lighting control, it is possible to combine easy installation using the existing 1-10 V interface with the comfort of intelligent lighting control. This means that DALI closes the gap between previous 1-10 V technology and expensive bus systems.

DALI is an interface for Electronic Control Gear (ECG). DALI makes it possible to control the ECG digitally and enjoy all the functionality as required. This means that an ECG designed to conform to this standard is able to carry out the commands issued by a control device. DALI has been designed primarily for use with lighting systems. The functionality of every DALI ECG within a lighting system exceeds by far any previous analog 1-10 V interfaces.

DALI was developed by all the leading ECG manufacturers who came together to define the functions of a DALI-ECG and a load conforming to DALI within a lighting system.

DALI was created in the form of an industry standard in order to satisfy all the demands placed on modern lighting controls. Above all, it includes a facility for receiving feedback from the ECGs concerning their current state and also for storing certain scenario values in an ECG. Every DALI-ECG configuration is able to store 16 group constellations and 16 scenarios.

DALI product features:-
· Control via DALI interface (Digital Addressable Lighting Interface)
· Switchable via DALI control wire
· Addressable
· Dimmable from 100 % to 1 % luminous flux
· Power stabilization in the event of mains voltage fluctuations
· Suitable for emergency lighting
· The control input for the DALI interface is robust with respect to over voltage and reversal

More information is available at http://www.dali-ag.org.

The DALI AG, part of ZVEI of Germany, created the openDigital Addressable Lighting Interface standard, and is laid down in the global IEC document 60929

Problems Addressed/Issues

Luminaires and ballasts are supplied by a great variety of suppliers and are connected in various forms:
- independent
- in clusters
- in conjunction with building management systems with many different protocols.

For all these applications the DALI protocol can be used DALI AG is an open digital protocol for lighting ballasts
Approach

Status 

The DALI-protocol is nowadays well accepted in the lighting market for fluorescent- and High Intensity Discharge lamp-applications and Solid State LightingAdditional standardization documents containing protocol-extensions for emergency lighting, HID and low voltage lamp- applications are currently in specification status.

Applications

DALI for Lighting Control

Apart from regular lighting applications (switching, dimming, scene-setting), the DALI protocol also enables users to realise all kinds of lighting-group-clustering, scene-settings, dynamic- and passive-color variation-settings in combination with external digital activators.
Even status-feedback of devices can be monitored.

Building Management Systems
With help of widespread digital-to-digital conversion devices, DALI-driven lighting networks can easily be connected to Building Management Systems.

Plug & Play applications
DALI technology is also massively applied in smaller lighting installations Recently many DALI-based “plug & play” applications have been introduced, for which installers do not need any dedicated training. With these plug & play solutions give a rapid further acceleration of the growth of DALI-driven applications used.

Advantages/Benefits   

Full compatibility of all ballast and luminaire manufacturer with the DALI protocol

Interchangeability of ballasts and luminaires in existing installations.

16 individual groups can be formed out of the 64 addresses
16 light scenes can be defined individually
Limitations  

DALI is specified for 64 single addresses per cluster
For larger groups, beyond 64 addresses, multiplication of groups via a building management system is required.

Communications media

Fiber-optic cabling, bi-directional single-strand;
Powerline, spread-spectrum, 9-95kHz, 100-450kHz;
Powerline, narrow-band, 125-140kHz (BPSK);
TCP/IP, tunneling;
Twisted-pair wiring, bus;
Twisted-pair wiring, free-topology (powered or un-powered);
(some of the above are ANSI/EIA/CEA or EIA/TIA)

Other non-standardized media include:
Infrared;
Coaxial;
Radio Frequency
Communications rate
OSI layer(s)

System Description
Main DALI features and benefits compared to 1-10V analogue control systems
•    Individual control of fittings: each unit in the DALI network has it´s own individual address, therefore it is possible to communicate directly to the components in the fittings
•    Multichannelling use: through only one pair of control cable it is possible with DALI to control several different groups of fittings
•    No mains switching needed: the lights can be switched off by commands coming directly from the DALI control system making the mains switch unnecessary
•    Back-channelling: the information flow is bidirectional with the DALI system. Instead of only giving commands about the light level to the fitting DALI system enables also information feedback on the condition of the fittings. the fitting can transmit information about:-
o    whether the light is switched on or off,
o    the pre-set light level
o    the ballast condition
•    simple DALI wiring: the cabling consists of a simple two wire cable, independent of any building topology between the units in the system
•    Easy system re-configuration: once the system is installed and configured it is very easy to change the functioning of the system, changing of scenes and functions of lighting is only a matter of programming and needs no hardware changes anymore
•    easy to add new components: when the lighting system needs to be enlargened new components can be added anywhere in the DALI system, no wiring configuration rules apply on the DALI line in this aspect.
Main differences between DALI and building automation buses
•    DALI has a limited system size (64 addresses).
•    DALI is meant only for communication in lighting systems as BMS includes other functionality as well (HVAC, alarm systems…)
•    A BMS system commonly has unlimited expansion possibilities, which DALI does not have
•    DALI is not competing against BMS systems, it is only complementing them through an interface

System Guidelines

Functional compatibility
Compatibility of ballasts is guaranteed by the standard. For other units, like sensors and controllers the compatibility ensurance is in process and the and a standardization will be achieved. Compatibility has always to be ensured when a system is being designed.

System size
The maximum number of individual addresses available in the DALI standard is 64. The maximum DALI supply current is stated as 250mA maximum.

Maximum ballasts in a system
Up to 64 individual ballasts can be connected in a DALI line without exceeding the system node or power supply current limits. This, of course, does not allow for any DALI control devices to be connected to the system.

Ballasts and control units in a system
If control units using the DALI protocol are to be used in a system then the system size will be limited to either 64 nodes or 250mA total system current (whichever value is reached first). When a DALI system is to be constructed containing both ballasts and control units it should be ensured that these limits are not exceeded. If the system size exceeds the limitations there will be problems due to reduced signal integrity ? some devices may fail to communicate or respond to commands and the system operation will become unstable.

Routing
The maximum voltage drop on the DALI line may not exceed 2V, resulting in a maximum line length of 300 m, between the DALI components furthest apart.

Good practice
For the above mentioned reasons it is the task of the system planner to consider the power consumption of each component used and to plan the system in such a way that the system limitations are not exceeded.

Electrical Guidelines
Voltages and currents
In the DALI standard all values are specified at the control pins of the ballast. For the full system the situation is slightly different. In general the control line voltage in a DALI system is normally 16 V (between 22,4 and 9,5 volts) when there is no communication (idle state). This voltage is supplied from an internal DALI power supply. The digital signal becomes low when the voltage level in the DALI system becomes zero (-6,5V - 6,5V)

Supplying the system
In a DALI system the maximum system current is limited to 250mA, which is supplied from additional power supplies. This is to keep the energy consumption low and to ensure digital signal integrity throughout the system. The smallest possible system, one light fitting and a controller consunes a line current of maximum 2 mA for the digital dimmable ballast and the current required by the control equipment. Thus the power consumed is small. Since in practice the impedance of different DALI units are not identical, the selection of the correct system power supply not necessarily straight forward. Good practice is to allow sufficient margins for the supply current. This will guarantee reliable system functionality under different conditions and also allow the flexibility for possible system expansion at a later date. On the other hand, selecting an oversized power supply may cause extra distortion control signals Power supplies, which have so called dynamic current limitation, will be suitable for use in almost every size of system.

Requirements for DALI power supplies.
The DALI power supply must limit the supply current to max. 250 mA under all circumstances. In practical installations the current is good to limit to a lower level in order to maintain the flexibility of changing the layout and increasing the system at later stages. If the limit is exceeded instability and starting problems may occure in the system. Since the DALI signal varies between 0V and 16V the polarity is important to maintain also with power supply. There is no limitation to having several power supplies on the same DALI control line as long as the current limit is not exceeded and the supply polarity is taken into account.

DALI - LIGHTING WITH INTELLIGENCE
(DALI - Digital Addressable Lighting Interface)
The new method involves using DALI-protocol-based technology (i.e. digital control signals) to control electronic ballasts, controllers and sensors belonging to the system. Each system component has its own device-specific address, and this makes it possible to implement individual device control.

History of the DALI protocol
Research work connected to the DALI project began midway through the 1990s. However, the development of commercial applications got under way a little later, in the summer of 1998. At that time, DALI went under the name DBI (Digital Ballast Interface). An interface device (or ballast) is an electronic inductor enabling control of fluorescent lamps. In addition to the work done at Helvar, the DALI standard has been the subject of R&D by other European ballast manufacturers such as Hüco, Philips, Osram, Tridonic, Trilux and Vossloh-Schwabe. The DALI standard will be added to the European electronic ballast standard “EN60929 Annex E”. Different manufacturers´ products can be interconnected provided that the manufacturers adhere to the DALI standard. This standard embodies addressability, i.e. ballasts can be controlled individually when necessary. To date, ballasts connected to an analogue 1-10 VDC low-voltage control bus have been subject to simultaneous control. Another advantage enabled by the DALI standard is communicating the status of ballasts back to the control unit. This is especially useful in extensive installations where the light fixtures are widely distributed. The execution of commands compliant with the DALI standard and obtaining the status data presuppose intelligence on part of the ballast. This is provided by mounting a microprocessor within the ballast; the microprocessor also carries out other control tasks. The first products based on the DALI technology were commercially available from the end of 1999.

DIGITAL CONTROL
The word “digital” is a term which has become familiar to us all in the course of this decade in connection with the control technology built into domestic appliances as well as into industrial processes. Now, digital control is becoming increasingly common in the lighting industry under a new concept bearing the name DALI.

DALI MESSAGE STRUCTURE
DALI messages comply with the Bi-Phase, or Manchester, coding in which the bit values “1″ and “0″ are presented as two different voltage levels so that the change-over from the logic level “UNTRUE” to “TRUE” corresponds to bit value “1″, and the change-over from the logic level “TRUE” to “UNTRUE” corresponds to the bit value “0″. The coding includes error detection and enables power supply to the control units also when there are no messages being transmitted or when the same bit value is repeated several times in succession. The bus´s forward frame (from the control unit to the ballast) is comprised of 1 START bit, 8 address bits, 8 data/command bits, and 2 STOP bits. The backward frame (from the ballast to the control unit) is comprised of 1 START bit, 8 data bits and 2 STOP bits. The baud rate is 2400.

DALI messages consist of an address part and a command part. The address part determines which DALI module the message is intended for. All the modules execute commands with “broadcast” addresses. Sixty-four unique addresses are available plus sixteen group addresses. A particular module can belong to more than one group at the one time.
The light level is defined in DALI messages using an 8-bit number. The value “0″ (zero) means that the lamp is not lit. The DALI standard determines the light levels so that they comply with the logarithmic regulation curve in which case the human eye observes that the light changes in a linear fashion. All DALI ballasts and controllers adhere to the same logarithmic curve irrespective of their absolute minimum level. The DALI standard determines the light levels over a range of 0.1% to 100%. Level 1 in the DALI standard corresponds to a light level of 0.1%.

TYPICAL DALI MESSAGES
Go to light level xx.
Go to minimum level.
Set value xx as regulation speed.
Go to level compliant with situation xx.
Turn lamp off.
Query: What light level are you on?
Query: What is your status ?

FROM ANALOGUE TO DIGITAL
The idea concerning the DALI protocol emerged when the leading manufacturers of ballasts for fluorescent lamps collaborated in the development of a protocol with the leading principle of bringing the advantages of digital control to be within the reach of as many users as possible. Furthermore, the purpose was to support the idea of “open architecture” so that any manufacturer´s devices could be interconnected in a system. The precondition to this was for the manufacturers to commit themselves to the DALI standard.

In addition to control, the digital protocol enables feedback information to be obtained from the lighting fixture as to its adjustment level and the condition of the lamp and its ballast.

Examples of typical applications for the new system are office and conference facilities, classrooms and facilities requiring flexibility in lighting adjustment. The lighting-control segment based on DALI technology consists of maximum 64 individual addresses which are interconnected by a paired cable. DALI technology enables cost-effective implementation of lighting control of both smart individual lighting fixtures as well as of numerous segments connected to the automation bus of a building.

ADVANTAGES IN INSTALLATION AND USE
To understand the function of a simple light switch is something that everybody can do. It turns on and off the light. To get a more complicated lighting control system to be easy to control, without problem for the user, is now possible. The challenge facing new control systems is for them to be able to offer a flexible and easy-to-use means of lighting control with respect to the demands of both users as well as the facility. All the components of the DIGIDIM system can be controlled either independently or in a group. This being the case, DIGIDIM enables the flexible use of lighting control to different situations. The creation of variable lighting situations is especially important in conference rooms, offices, restaurants and other such multiple-use facilities. A soft transition from one lighting situation to another is possible thanks to programmable adjustment speeds. The system can be flexibly reprogrammed as the need arises, e.g. when using partitions. Also, the system enables the control of different combinations of light sources, e.g. ordinary fluorescent lamps, miniature fluorescent lights, discharge lamps, incandescent lamps and halogen lamps.

In their simplest form, installation and application can be implemented using the devices by connecting only the mains supply cable to the lighting fixtures and the control cables between the various components. DIGIDIM pushbuttons include lighting control levels compliant with the basic programming, and thus the system is ready to be used once the cabling has been completed. Modifications in the lighting levels are easy to perform directly via a pushbutton by adjusting the lighting to a suitable level with the Up/Down buttons and by finally saving the desired lighting level to one of the lighting-level recall pushbuttons. When programming more extensive systems, a PC-based installation program can be used for creating different lighting groups.

USER CONVENIENCE AND COST EFFICIENCY
In northern parts of Europe, like Scandinavia, the use of cooling air condition systems can be needed to use more then 6 months a year. Part off that energy is for cooling the heath dissipation from luminaries. In buildings provided with gravity-based ventilation, lighting can account for as much as 40% of the energy costs, and in buildings with air conditioning, lighting and ventilation can constitute an even more significant part of the energy costs. Using constant light control and presence detection can ver much reduce these costs. If we take an example: In an office with standard luminaries, the energy consumption for light can be reduced with up to 80% if a solution with new T5 tubes, constant light and presence detection is installed. Also, constant light control adds to the user convenience of the persons in the facility because the system always, and automatically, executes the lighting level desired by the user. Poor lighting has a detrimental effect on people, and it can ultimately cause eyestrain and headaches.

Further information:
AG-DALI: http://www.ag-dali.org

Performance Standard: IEC 929 / EN60929 Annex E (Control Interface for Controllable Ballasts)

Summary:
DALI - Digital Addressable Lighting Interface - brings the benefits of a new industry standard to lighting-control systems. It has been developed specifically with optimum lighting control in mind, both in local room control applications and when interfacing with building management systems. The DALI protocol, based are a draft amendment to IEC 929, has been adopted as a new standard by major ballast manufacturers such as Helvar, Hüco, Philips, Osram, Tridonic, Trilux and Vossloh-Schwabe. As a dedicated communication interface for the control of lighting systems, DALI enables sophisticated lighting control while greatly increasing flexibility and reducing installation costs.

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General information on Oil Storage Tanks

10/06/2009 by David Slade.

Lets get the regulations and enforcement compliance’s out of the way first.

The facts:

Control of Pollution (Oil Storage) (England) Regulations 2001
Every year more than 5000 oil incidents are reported to the Environment Agency, that’s nearly 14 every day!.
Most incidents were caused by oil leaking from tanks either during storage or delivery. The Oil Storage Regulations will help us to stop these incidents by requiring tank owners to provide a secondary containment facility, such as a bund or drip tray to prevent oil escaping into the water environment.

Anyone storing oil in containers greater than 200 litres, above ground at an industrial, commercial or institutional site, or more than 3500 litres at a domestic site will be affected by these regulations. They cover factories, shops, offices, hotels, schools, churches, village halls, public sector buildings and hospitals.

•    Oil stores installed since 1st March 2001 must comply.
•    Existing oil stores “at significant risk” should have complied since 1st September 2003.
•    Existing oil stores must comply from 1st September 2005.

In general, an oil store is at “significant risk” if located within 10 metres of a watercourse or 50 metres of a well or borehole.

How are the regulations enforced?
The Environment Agency is responsible for enforcing these regulations throughout England. Should your oil storage facilities be inadequate, the Agency will provide advice and guidance to assist you with compliance. However, if you fail to act, the Agency may serve a notice requiring that the facilities be brought up to standard. Failure to comply with a notice is a criminal offence and may result in prosecution.

The regulations do not apply :

•    at premises used wholly or mainly as a single private dwelling storing less than 3500 litres. (but Building Regulations do apply for new and replacement domestic tanks);
•    at premises used for refining oil or its onward distribution;
•    any oil stored in a building or wholly underground;
•    to agricultural use of oil on farms - the storage of agricultural fuel oil is subject to the Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) Regulations, 1991;
•    to waste mineral oil.

Requirements for storage of oil - general
Oil shall be stored in a container which is of sufficient strength and structural integrity to ensure that it is unlikely to burst or leak in its ordinary use.

The container must be situated within a secondary containment system which satisfies the following requirements - it must have a capacity of not less than 110% of the container’s storage capacity or, if there is more than one container within the system, of not less than 110% of the largest container’s storage capacity or 25% of their aggregate storage capacity, whichever is the greater; (b) it must be positioned, or other steps must be taken, so as to minimise any risk of damage by impact so far as is reasonably practicable; (c) its base and walls must be impermeable to water and oil; (d) its base and walls must not be penetrated by any valve, pipe or other opening which is used for draining the system; and (e) if any fill pipe, or draw off pipe, penetrates its base or any of its walls, the junction of the pipe with the base or walls must be adequately sealed to prevent oil escaping from the system.

Any valve, filter, sight gauge, vent pipe or other equipment ancillary to the container (other than a fill pipe or draw off pipe or, if the oil has a flashpoint of less than 32°C, a pump) must be situated within the secondary containment system.

Where a fill pipe is not within the secondary containment system, a drip tray must be used to catch any oil spilled when the container is being filled with oil.

Where any drum is used for the storage of oil in conjunction with a drip tray as the secondary containment system, it is sufficient if the tray has a capacity of not less than 25% of - (a) the drum’s storage capacity; or (b) if there is more than one drum used at the same time with the tray, the aggregate storage capacity of the drums.

Fixed tanks

Any fixed tank used for storing oil shall satisfy the following requirements:-

Any sight gauge must be properly supported and fitted with a valve which must be closed automatically when not in use.

Any fill pipe, draw off pipe or overflow pipe must be positioned, or other steps must be taken, so as to minimise any risk of damage by impact so far as is reasonably practicable and  (i) must have no mechanical joints, except at a place which is accessible for inspection by removing a hatch or cover; (ii) must be adequately protected from physical damage; (iii) must have adequate facilities for detecting any leaks; (iv) if fitted with a leakage detection device which is used continuously to monitor for leaks, the detection device must be maintained in working order and tested at appropriate intervals to ensure that it works properly; and (v) if not fitted with such a device, must be tested for leaks before it is first used and further tests for leaks must be performed, in the case of pipes which have mechanical joints, at least once in every 5 years and, in other cases, at least once in every 10 years; and (a) if above ground, must be properly supported; (b) if underground - be made of materials which are liable to corrosion, must be adequately protected against corrosion. The tank must be fitted with an automatic overfill prevention device if the filling operation is controlled from a place where it is not reasonably practicable to observe the tank and any vent pipe.

Any screw fitting or other fixed coupling which is fitted and is in good condition must be used when the tank is being filled with oil.

Where oil from the tank is delivered through a flexible pipe which is permanently attached to the container - (i) have a lockable valve where it leaves the container which is locked shut when not in use; and (ii) be kept within the secondary containment system when not in use. (a) The pipe must be fitted with a tap or valve at the delivery end which closes automatically when not in use; (b) the tap or valve must not be capable of being fixed in the open position unless the pipe is fitted with an automatic shut off device; (c) the pipe must be enclosed in a secure cabinet which is locked shut when not in use and is equipped with a drip tray or the pipe must

Any pump must be - (a) fitted with a non-return valve in its feed line; (b) positioned, or other steps must be taken, so as to minimise any risk of damage by impact so far as is reasonably practicable; and (c) protected from unauthorised use.

Any permanent vent pipe, tap or valve through which oil can be discharged from the tank to the open must satisfy the following requirements -

(a) it must be situated within the secondary containment system;
(b) it must be arranged so as to discharge the oil vertically downwards and be contained within the system; and
(c) in the case of a tap or valve, it must be fitted with a lock and locked shut when not in use.This applies to England but the same enforcement principles are applied elsewhere.

Bundled tank questions that I’ve often been asked?

Introduction

There is confusion about the terms “double skinned”, “integrally bunded”, “twin walled” and “bunded” plastic and steel tanks in relation to above ground oil storage, and which are acceptable from an environmental protection point of view. Unfortunately manufacturers and suppliers of these tanks have used a variety of these terms with different interpretations.

Double Skinned Tanks

A Double Skinned Tank is just that – a primary tank with another “skin” placed around it with a very small gap (interstitial space) between the two; none of the pipework or ancillary equipment is contained. The risk of oil being lost from ancillary equipment and pipework is high; the Control of Pollution (Oil Storage) Regulations 2001 recognises this fact and require that tanks have all ancillary equipment such as sight tubes, taps and valves retained within a secondary containment system.
Double skinned tanks are not compliant with the Control of Pollution (Oil Storage) (England) Regulations 2001 unless additional secondary containment is provided for the tank and it’s ancillary equipment, such as an in-situ constructed bund (see Environment Agency/CIRIA Guidance notes on Masonry and Concrete bund construction).

Double Skinned Tanks are recommended for underground storage of oil/petrol etc because the interstitial space between the tank skins can be monitored for leaks. Underground installations should also have twin walled, non-corrosive pipework specified. See Pollution Prevention Guidance Note 27 – Installation, Decommissioning and Removal of Underground Storage Tanks, PPG7 – Refuelling Facilities (currently under revision) and the DEFRA Groundwater Protection Code: Petrol stations and other Fuel Dispensing facilities Involving Underground Storage Tanks.

Proprietary Tank Systems

Proprietary Tank Systems come in a large range of designs and are produced by many different manufacturers who may make certain claims about the environmental performance of their products. Proprietary Tank System or just Tank System is the preferred generic term for tanks often referred to as integrally bunded or twin walled, to prevent the confusion described above. Some tanks systems may have adequate secondary containment to comply with Oil Storage Regulation requirements, but some may be regarded as “high specification primary containers” and would therefore be non-compliant without additional containment.

To comply with the Control of Pollution (Oil Storage) (England) Regulations 2001, tank systems must have containment to minimise damage from third party interference, prevent pollution incidents from overfilling, leaking primary container or ancillary equipment. They should be sited to minimise the chance of damage by impact or collision or protected by suitable physical barriers.

If well designed, manufactured, sited, installed, used and maintained correctly a tank system can be just as effective as a conventional in-situ bunded tank.

The Environment Agency’s Pollution Prevention Guidance Note 2 - Above Ground Oil Storage Tanks gives some basic principles about the points to look out for when considering a tank system, products can be assessed against the check list.
If you have any queries about oil tanks and the Regulations in England or Wales please email oil.regulations@environment-agency.gov.uk

OTHER DATA

CIRIA (Construction Industry Research and Information Association) is a UK based association concerned with improving the performance of all involved in construction and the environment.
•    C I R I A /Environment Agency Joint Guidelines: Concrete Bunds for Oil Storage Tanks Guidance for the construction of simple, reinforced concrete bunds for oil storage tanks up to 3.5 metres wide and 900mm high. It is based upon CIRIA Report 163 “Construction of bunds for oil storage tanks”

DEFRA Oil Storage Regs DEFRA guidance note on the oil regulations

•    C I R I A /Environment Agency Joint Guidelines Masonry Bunds for Oil Storage Tanks. Guidance for the construction of simple, reinforced masonry bunds for oil storage tanks up to 3.5 metres wide and 1200mm high. It is based upon CIRIA Report 163 “Construction of bunds for oil storage tanks”
•    PPG02 Above ground oil storage tanks - Guidelines to assist those responsible for above ground oil storage tanks at sites other than oil refineries and distribution depots.
•    PPG26 Storage and Handling of Drums & Intermediate Bulk Containers - These notes are intended to assist all who deal with the storage and handling of drums and Intermediate Bulk Containers (IBCs).
•    Pollution Prevention Guidance Notes (PPGs)
Targeted at a particular business sector or activity PPGs provide advice to industry and the public on statutory responsibilities and good environmental practice.
•    Pollution incidents – an overview
In England and Wales, there were over 29,000 substantiated pollution incidents in 2003.

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