Tech Thursday – REACH (for the stars!)

Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH)

REACH came into force on 1st June 2007, essentially an environmental and health & safety initiative to identify where and how chemicals are used across all industries, and how they might impact both people (employees and users) and the environment.  It is an evolving regulation, and one to which depending on the position of the item in the “process chain”, differing responses are required.

Candidate List of Substances of Very High Concern (SVHC).

REACH has associated with it a list, entitled the Candidate List of Substances of Very High Concern, generally referred to as SVHC. The SVHC is a list of substances (predominantly chemicals), which have been identified as having a potentially detrimental effect on a person’s health if used in an uncontrolled manner.  According to set criteria, any preparation or article containing one of these SVHC must be accompanied by a Safety Data Sheet, clarifying how it should be used, under what circumstances it is “safe”, any Personal Protective Equipment (PPE) which should be worn, how to dispose of excess preparation with regard to the environment and personal safety, and how to deal with incidents involving the substance, such as fire, spills, accidents and so on.

The SVHC Candidate list is periodically updated, as substances are found or suspected to be detrimental to health or the environment.  As chemicals are added to the list, the supply chain is obligated to alert downstream users of any implications.  The latest update was 19th December 2012, when a further 54 substances were added.  At the date of this article SVHC now contains 138 substances.

Obligations under REACH

Depending on a company’s operation their obligations under REACH differ.  There are essentially three types of company as far as REACH is concerned – Manufacturer, Importer and Downstream User.

Manufacturers and Importers: From 1 June 2008, any company which manufactures any substance used on its own, or in preparations or in articles, in quantities of 1 tonne or more per year, must ensure that substance is registered with the European Chemicals Agency (ECHA) prior to its manufacture in the EU or placement on the market, subject to certain exemptions. This obligation is imposed on any manufacturer or importer of a substance on its own or in a preparation and to article producers / importers under certain conditions.

Where importers buy anything from outside the EU/EEA, be it chemicals, blends, or finished goods, for instance a “scratch and sniff” piece of clothing or toy, there are likely some responsibilities under REACH.

Downstream users: Under the REACH regulation, many companies, including D. G. Controls Ltd are classified as an end-user, since they produce nothing per se, they construct items based on previously processed parts.

The obligations of a downstream user are firstly to seek evidence from its component suppliers that all substances which need to be registered have been, and secondly to ensure that those component suppliers advise of any substances included in items supplied which are listed in the Candidate List of Substances of Very High Concern (SVHC).   Should this be the case, any preparation or article containing one of these SVHC must be accompanied by a Safety Data Sheet detailing the Safe Handling and Disposal methods for that substance.

If you have any particular enquiries regarding REACH and the deegee range of beacons and sounders, please make contact initially with our Sales Department and they can ensure your enquiry is dealt with by the most appropriate support member.

There is a wide range of information about REACH on the internet, but a particularly useful and easy to understand site is http://www.hse.gov.uk/REACH/about.htm

 

Congratulations to the team!

Congratulations to the team!

D. G. Controls Ltd has been an “Investor in People” since 2000, and has always recognised the importance of having well-trained staff in its teams. Internal and external training-providers are used, and all staff are encouraged to develop themselves within their current roles and their potential capabilities. Even though we are a fairly small company in terms of numbers, through well-managed delegation and fostering trust and accountability, we have a culture of developing individuals in their skills and experiences, even where out-right promotion is not always a possibility.

To that end we recognise the following individuals who have “stepped-up” to develop themselves in their roles, and in the process helped the business to run that bit more effectively and efficiently.

Well done Donna Sidwells for completing her Supervisory Training just before the Christmas break. Donna was promoted from the Manufacturing Team to Factory Supervisor about 18 months ago, but it was quite difficult to get some good formal basic training and guidance to help her in this transition “from friend to supervisor”. The course run by Lawrence Training was a great start. As Donna said when she returned, “The biggest thing I learnt was how to see myself more as others see me. It has really helped me to focus on how I am perceived in my job, as well as how I perceive myself. It was really helpful.”

Congratulations also to Elliot Rose from the Manufacturing Team for his recent certification as a Fork Lift Truck Driver. Attending a week-long off-site Fork Lift course, Elliot gains his Fork Lift Driving Licence and registration onto the RTITB Nors System. Elliot was well-prepared on his return to re-organise the storage areas in the D. G. Controls factory, and has taken over all the routine maintenance and checks on the Linde Lansing machine. “I really enjoyed it,” said Elliot of the course, run by RTS Training Ltd. “Big boys toys” I think would be our response!

A large part of D. G. Controls’ sales interaction takes place over the telephone, and to help “up-our-game,” the UK sales team went for an intensive day’s training with Derbyshire & Nottinghamshire Chamber (DNCC) on telephone skills, both regarding incoming calls and outgoing calls. Called “Maximising the Enquiry”, the presenter worked with the team to adapt questioning techniques, capture information, and generally make sure they get the most they can do out of that time on the phone with our customers and potential customers. Whilst already well-versed in telesales techniques, and “not teaching grandmothers to suck eggs,” Lisa Baum, Stacey Porter and Jo Lovatt all came back with a fresh insight on how this non-visual sales technique works, and how they can move onto the next level with this crucial part of our business.

 

Tech Thursday – Light Part 3 – Colour

This is the final instalment in our short three part series discussing Light.

  1. In the first part we will briefly looked at what we define light to be and went on to discuss some of the photometric units that are typically found in photometric measurements.
  2. In the second part we discussed Luminous Intensity and in particular how we go about measuring it in a meaningful way.
  3. In this final part we round-up the series with a brief introduction to colour, its measurement and the typical colour definitions used in signalling.

Colour

Definition and Measurement

 

Standard Colour Definitions & Meaning

Whilst we are unable to find a standard that directly defines the colour coding of warning beacons or visual alarm devices (VADs) we can borrow from the existing standard BS EN 60073 – “Basic and safety principles for man-machine interface, marking and identification – coding principles for indicators and actuators”

From this standard we shamelessly borrow the table:

Colour

Safety of persons or environment

Condition of process

State of equipment

Red

Danger

Emergency

Faulty

Yellow

Warning/Caution

Abnormal

Abnormal

Green

Safe

Normal

Normal

Blue

Mandatory significance

White (Grey or Black)

No specific meaning assigned

This standard does not directly define what is meant by the individual colours in terms of chromaticity – for example what do we mean by red?  Instead it refers us to CIE publication No. 2-2 1975 – “Colours of light signals” which has now been superseded by standard CIE S 004/E-2001 – “Colours of light signals”.  Here may be found exact definitions of what constitutes Red, Yellow, Green, Blue and White light signals.

Summary

This is the final instalment of the three part series discussing various properties of light.  We very briefly looked at Colour and its measurement as well as how we can usefully apply colour to signalling situations in a uniform standardised manner.

Tech Thursday – EN54-23

What is EN54-23?

EN54-23 or to give it its full title “Fire detection and fire alarm systems – Part 23: Fire alarm devices – Visual alarm devices”, was produced to standardise the requirements, in terms of construction, robustness and performance of warning beacons used within a fire detection system.  The purpose of the beacons being to warn personnel of a fire emergency so that they can take the necessary action.  Throughout the term Visual Alarm Device (VAD) is used to refer to such beacons.

In the UK the Disability Discrimination Act (DDA) introduced to people the need to provide an alternative fire alarm signal for those who are deaf or hard of hearing.  However, in addition, there has always been a requirement to provide the appropriate signalling where it would otherwise be difficult to hear a traditional fire alarm sounder/bell due to high ambient noise levels and/or where ear protection is routinely worn.

Whilst the requirement to provide a visual signal is therefore very clear, there existed little guidance on what performance level(s) such devices needed to meet.  This is further compounded by manufacturers quoting a plethora of different performance figures using terms such as Joules, Watts, Lumens, Luminous Intensity, Effective Luminous Intensity, Peak Luminous Intensity or just “Brightness”!  :

Joules : a measure of energy.  This is typically used to quote the energy expended in a single, or sometimes multiple, flash(es) of a xenon strobe beacon.  To determine how visible such a product is we need to know the efficiency of the flash tube and associated optics (including any de-rating for colour) as well as the flash waveform.

Watts : a measure of power – typically electrical power.  Similar to the Joules figure quoted for a xenon strobe beacon, this may also be applied to any VAD such as LED or filament lamp.  As we are concerned with the electrical power consumed by a visual warning device, in addition to the factors above, we also need to consider how efficiently the VAD converts electrical power to visible light.

Lumens :  This is a measure of the total amount of light emitted by the VAD and is the light equivalent to the Watt (See our previous article on Light).  Whilst this is good that we are starting to consider the light produced by the device as a whole, rather than power consumed, it is a little meaningless as is does not consider whether any of the light produced is directed in any useful manner.

Luminous Intensity – Candela (Cd):  This is a measure of the light emitted in a given direction and for a steady burning light it is quite easy to measure.  In common with Lumens above, it does not consider whether this light is targeted in any useful direction.  To further compound matters, manufacturers nearly always quote the best measured figure and fail to quote in which direction that light was emitted.

Peak Luminous Intensity  – Candela (Cd):  This, along with Effective Luminous Intensity below, is typically quoted for flashing (non-steady) VADs.  It is usually quoted as the maximum luminous intensity of a single flash, typically in whatever direction yields the greatest figure.  It has a great problem in that with the short duration flashes from a VAD it fails to account for how the eye perceives the flash – a very short but very high intensity flash may actually appear less bright than a lower intensity, but longer flash due to how we see flashing lights and is therefore meaningless when comparing products or even products to specifications.

Effective Luminous Intensity  – Candela (Cd) : In recognition of the issues with Peak Luminous Intensity above, Effective Luminous Intensity is defined by E. Allard as the “luminous intensity (cd) of a steady light, of the same spectral distribution as the flashing light, which would have the same luminous range as the flashing light under identical conditions of observation”.  In other words, how bright does the flashing light appear to be compared to a non-flashing light.  This necessarily takes into account the flash-rate, flash-pattern and individual pulse shapes and provides a figure that is easily compared across different types of light source.  However, in common with the other measurements, this is usually quoted by the manufacturers in the direction that yields the most favourable result without considering whether the light is directed anywhere useful.  To further complicate matters, there are numerous methods for calculating the Effective Luminous Intensity that may or may not yield the same numerical answer depending on the exact flash-rate, flash-pattern and individual pulse shape of the light being measured!

Brightness : Often quoted by LED product manufactures as “High-brightness”, “Ultra-bright”, “Super-bright” or other such meaningless descriptions.  As there is no standard definition as to what these mean – even within a single manufacturer’s range – it is impossible to compare performance with a required standard.

All of this meant that comparison amongst products, let alone verification to a standard, was effectively impossible.  Indeed, who would ever be able to confidently state that a proposed or installed VAD met the stated objective of being able to warn personnel of a fire emergency so that they can take the necessary action?

 

If luminous intensity (in its various incarnations) moved us from discussing consumption (Power or Energy) to what was produced (Light in a direction outside the VAD), EN54-23 wraps all of this up into a nomenclature that puts a numerical number to Coverage Volume – away from the individual VAD as a product and towards its application in the field.  A good move in my opinion.

The Coverage Volume quoted is the size of the space in which the VAD is effective.   There are three categories of product (Ceiling, Wall and Open) and each quotes its coverage in a slightly different manner – see Product Markings below.  From this figure we can readily compare differing products and from that design the configuration of one or more VADs within the real-world space we have to provide signalling for.

 

What are the requirements for an EN54-23 compliant Visual Alarm Device?

The performance and test requirements are quite rigorous – this is necessarily so in order that we can simplify the product classification and marking to allow straightforward system design.  In summary, the requirements are as follows:

Coverage Volume

The VAD will classified in one of the following three ways:

C-x-y : Ceiling device

C : Ceiling

x : 3, 6 or 9 and represents the maximum height in meters that the product may be mounted.

y : The diameter in meters of a cylinder within which the product is deemed to comply

Example: C-3-12 denotes a ceiling device that is good for a 12m coverage cylinder when mounted at a height no more than 3m from the ground.

W-x-y : Wall device

W : Wall

x : Maximum height in meters that the device can be mounted on the wall. The minimum allowable height is 2.4m.

y : The width of a square room within which the product is deemed to comply.

Example: W-3,3-6 denotes a wall mounted device that may be mounted between 2.4m and 3.3m from the floor and is good for a volume of 2.4m x 6m x 6m.

Variation of light output

The measured performance of the VAD must not deviate by more than 25% over a 30 minute period.

Luminous Intensity Limits

The VAD must produce a luminous intensity of 1cd for 70% of all measurement points and not exceed 500cd for any measurement point.

Light colour

                The emitted flashing light must be either Red or White.  No guidance is given as to what Red or White are in terms of chromaticity.

Light flash pattern and frequency

The frequency must fall within the range 0.5Hz and 2Hz.

The maximum On time must be no more than 0.2 seconds.

For multiple pulse signals, pulse trains can be considered as a single pulse where the inter-pulse gap is less than 0.04 seconds.

Marking

The VAD must be marked with the following information:

EN54-23

Environment type (Type A or Type B)

Device category (e.g. W-2,4-6)

Name/trademark of manufacturer or supplier

Model designation/number

Terminal designations

Serial number/batch code to allow manufacturer to establish date and place of manufacture along with software revision if appropriate

Data

Within the datasheet/manual supplied with the device:

EN54-23

Environment type (Type A or Type B)

Device category (e.g. W-2,4-6)

Name/trademark of manufacturer or supplier

Model designation/number

Terminal designations

Serial number/batch code to allow manufacturer to establish date and place of manufacture along with software revision if appropriate

Rated supply voltage or ranges (AC or DC)

Power and current consumption

Supply frequency ranges if relevant

Coverage characteristics including how to orient the device if applicable

Flash pattern and frequency

IP Rating as per EN60529:1991

Any other relevant information pertaining to the installation, use or maintenance of the VAD

Synchronization – if appropriate

If multiple VADs are to be synchronized together, then the difference in flashes between two beacons must be no more than 0.02 seconds and thereafter drift to no more than 0.05 seconds over a period of 30 minutes.

 

Durability

In addition to the performance criteria above, the VADs must endure the following:

Work correctly at high temperatures: 16 hours at 55C for Type A / 70C for Type B

Endure high temperatures (off state):  21 days at 70C for type B

Work correctly at low temperatures : 16 hours at -10C for Type A / -25C for Type B

 

Work correctly at high levels of humidity:

Type A – 2 cycles of 25C >95% RH to 40C 93% RH

Type B – 2 cycles of 25C >95% RH to 55C 93% RH

Endure high levels of damp heat : 21 days at 40C 93% RH

Endure cyclic damp heat: Type B 6 cycles of 2 cycles of 25C >95% RH to 40C 93% RH

 

Work correctly when submitted to mechanical shocks

Work correctly when submitted to mechanical impact

Work correctly when submitted to sinusoidal vibration

Endure the effect of sinusoidal vibration

 

Endure the effects of corrosive atmosphere: 21 days 25ul/l SO2 at 25C and 93% RH

 

Work correctly when submitted to electromagnetic interference

 

Application

Loss Prevention Code of Practice CoP 0001 – Code of Practice for visual alarm devices used for fire warning provides recommendations for the planning, design, installation, commissioning and maintenance of VADs in and around buildings.  It does not directly advise if VADs should be used but rather how they should be installed and guidance on their location.

 

I trust that this has been a useful guide – Whilst we have made all efforts to ensure the accuracy of this information, no liability can ne accepted for any errors or omissions contained therein.  That said, do make contact if you would like further information or, indeed, if you have anything further to add!

Tech Thursday – Light Part 2 – Luminous Intensity and its measurement

This is the second instalment of a short three part series discussing Light.

  1. In the first part we briefly looked at what we define light to be went on to discuss some of the photometric units that are typically found in photometric measurements.
  2. In this second part continue on to discuss Luminous Intensity and in particular how we go about measuring it in a meaningful way.
  3. In the final part we round-up the series with a brief introduction to colour, its measurement and the typical colour definitions used in signalling.

Luminous Intensity

As discussed in part 1, Luminous Intensity is a measure of the light emitted in a given, or defined, direction.  For a static (non-flashing) light source it is very simple to measure the light in the given direction and to then quote a meaningful figure for luminous intensity.  Further, with the use of a goniophotometer it is fairly straightforward to measure the intensity in a number of directions and produce a 3d map of the resulting data.

Things get complicated as soon as we start to look at flashing light sources such as warning beacons (also known as visual alarm devices or VADs) as the relatively slow response of the human eye to pulsed light plays a large part in dictating how bright the flashing light appears.

Peak vs. Effective Luminous Intensity

Peak Luminous Intensity, along with Effective Luminous Intensity below, is typically quoted for flashing (non-steady) warning beacons.  As it is usually quoted as the maximum luminous intensity of a single flash, typically in whatever direction yields the greatest figure, an impressive looking figure is available for marketing datasheets.  The problem is that quoting just the maximum measurement of the short duration flashes from a warning beacon fails to account for how the eye perceives the flash – Our experience has shown us that a very short but very high intensity flash may actually appear less bright than a lower intensity, but longer flash due to how we see flashing lights and is therefore meaningless when comparing products or even products to specifications.

Effective Luminous Intensity recognises the issues with Peak Luminous Intensity above and attempts to standardise a meaningful measurement.  Effective Luminous Intensity as defined by E. Allard is the “luminous intensity (cd) of a steady light, of the same spectral distribution as the flashing light, which would have the same luminous range as the flashing light under identical conditions of observation”.  In other words, how bright does a flashing light appear to be compared to a similar non-flashing light.  This necessarily takes into account the flash-rate, flash-pattern and individual pulse shapes and provides a figure that is easily compared across different types of light source.  To further complicate matters, there are numerous methods for calculating the Effective Luminous Intensity that may or may not yield the same numerical answer depending on the exact flash-rate, flash-pattern and individual pulse shape of the light being measured!  There is a great paper on this subject written by Yoshi Ohno of NIST that can be downloaded from here.

Measurement

The measurement process of the Peak Luminous Intensity is relatively straightforward.  We have in the past connected a standard Lux meter to an oscilloscope and used this to capture a plot of the flash event.  Quoting the peak luminous intensity is as simple as reading off the maximum value and scaling the result to candelas.

We measured the Effective Luminous Intensity in a similar fashion but, rather than just reading off the result we apply the measurement, along with an estimation of the area bounded by the flash event, to one of the standard formulae and arrive at a figure that allows us to compare the luminous intensity across a range of our products and product technologies.

In more recent times we have automated these measurements by using a closed loop system that captures the flash event waveform and performs the calculations directly on the raw data.  One of the benefits is that we can directly compare the output of different integration methods to see what effect these have on the result.  This is a much faster process, that combined with a goniometer, provides a fast method of measuring the effective luminous intensity of a product in 3d space.

Summary

This is the second instalment of a three part series discussing various properties of light.  We very briefly looked at Luminous Intensity and how it relates to visual warning signals, the difference between Peak & Effective Luminous Intensity and why it matters and how we go about measuring the Luminous Intensity of warning signals.

In the final instalment we will be looking at:

  • Colour
  • Measurement of colour
  • The typical colour definitions used in signalling