1. THE WATER MANAGEMENT SOCIETY
www.wmsoc.org.uk ISSN 0954 7711 • Autumn 2016
The Journal of theWater Management Society
waterline
OrganicWaterTreatment
Current Guidelines & Myths - Part II
PLUS
Chair's Vision
Planning some plumbing work? Know the law
Thematic Sections
Carbapenem resistant organisms,
Water and the hospital environment
The latest BSI:
Where is your water going - Part 1
3. A U T U M N 2 0 1 6 feature article
30
The latest BSI:
where is your water
going - Part 1
by Susan Pearson
2015 saw the publication of a raft of new and updated BSI
guidance for the water industry but what are the practical
implications of the new BS 8554 and PD 855468 and updated BS
8558 in practice? A recent Water Management Society meeting
at the SCI (Society of Chemical Industry) in London provided an
opportunity to gain insight from members of the working parties
instrumental in drafting these documents.
The meeting was chaired by Tim white, Chair of the SCI’s environmental health and
safety group and the BSI’s sampling committee. Along with several of the speakers,
White repeatedly stressed the importance of feedback on standards from those that
use them: “it is difficult to write standards, we need industry consensus” he said, “so
we really need to engage in a dialogue with users. If a paragraph in a standard doesn’t
work for you, let us know what would work instead. We are really keen to receive
constructive criticism so that we can move standards forward for everybody.”*
With plenty of audience input, ‘The latest BSI guidance: where is your water going’
provided a forum for a lively discussion on topics such as the need for flushing v.
sustainability and the need to save water, the importance of design of water systems
and the financial implications of risk management. The meeting was unusual in
bringing a very wide range of expertise together and prompted some significant new
collaboration.
How standards are made
Tom Digby-Rogers, lead programme manager in BSI’s sustainability sector set the
scene for the conference by describing BSI’s role in making standards.
BSI is the UK’s only national standards body, a not-for-profit Royal Charter
organisation responsible for the drafting, implementation and maintenance of all
British standards. It is the only route for UK comment on European and International
Standards through bodies such as the European Committee for Standardization (CEN)
and the International Organization for Standardization (ISO), allowing consistency on
a “huge scale,” as well as providing an international platform for championing British
ways of working.
Digby-Rogers defined standards as open, consensus-based documents, developed by
experts from industry, government and academia who agree on best practice and
convert it into requirements, recommendations and guidelines. Standards exist for
“the common and repeated use, aimed at the achievement of the optimum degree of
order in a given context,” he said, to help organisations perform better, reduce costs,
manage risk, differentiate themselves in markets and grow sustainably.
Standards are entirely voluntary.While the industry does not have to use them, their
purpose is to enable industry to take positive action and can be used to support
compliance.A standard can help meet directives and some have standards written
into them, effectively making them mandatory, eg the Drinking Water Directive.
While ‘regulations’ are imposed,‘standards’ are “about industry taking control,”
Digby-Rogers said.As a tool they “cannot be underestimated..... a national standards
body ...creating a national standard ... allows industry, on a national level, to get
together around a new idea or challenge and collectively take action for the greater
good.”
BSI manages its work through a series of committees and panels working across
every discipline and all committee and panel membership is voluntary Committees
are made up of stakeholders who nominate experts in their fields.The role of the
committees is to help BSI look for gaps in good practice and highlight how standards
can address these unmet needs, via open, consultative collaboration.“BSI process
demands that all relevant voices are afforded equal importance in developing
standards, be they from industry, government, academia, NGOs / civil society or
consumer groups, and as a result the outputs are more robust and credible.”
The BSI produces several different ‘tools’ (see Table 1), all developed after several
levels of public consultation with the final draft put together by the panel after
discussion of all comments. The panels also work on revisions of documents to
update them in line with feedback from users.
However, Mr Digby-Rogers emphasised that European Standards must be
implemented as part of the UK’s agreement with CEN, taking precedence over UK
standards.This is not the case with international standards, which BSI can choose to
adopt.
Mr Digby-Rogers stressed that the strength of standards lies in the independence of
the committee and panel members and urged the audience to get involved.*
Table 1. BSI publications
• Specifications – requirements that have to be met in order for
conformity (compliance) to be claimed;
• Codes of practice – recommendations (should/may) on good practice,
usually for one or more processes or procedures, again demonstrates
compliance;
• Methods of test – detailed instructions for carrying out one or more
procedures for measurement, testing, sampling or
evaluating performance;
• Guides – more informative, not used for testing compliance. Used to
demonstrate what can be done to go further to provide greater quality.
• Corporate technical specifications and private standards.
The cost of failure
Giles Green, Chairman of WMSoc’s technical committee and Chair of the Legionella
Control Association, examined in detail what ‘risk’ actually means in the context
of a ‘risk assessment’ as set out in guidance such as ACOPs (approved codes of
practice) L8 and HSG 274. In particular, he examined the central notion ‘reasonably
practicable’, put forward in the 1974 Health and Safety at Work Act, and discussed
the literal ‘price of failure’.
Reasonably practicable means that the measures required to avoid putting somebody
at risk of harm should include taking into account the effect a harmful event has
on someone’s life. In a legal situation, a court needs to be satisfied that anything
that could possibly have been done, but was not, would have been unreasonable, or
impracticable to do. So risk assessments need to consider not only potential ‘hazards,’
but also the consequences that might ensue, factoring in the likelihood of both. 1,2
But how do you rationalize this? How might costs be balanced against the chances
of a harzardous event happening? Although it is impossible to place a value on
someone’s death, this rationalisation still has to be made, Green said, and the HSE
have put forward cash valuations, outlined in Table 2.
In determining how ‘ risk’ might be assessed, he set out an equation along the lines
of: Risk = Hazard x Likelihood (of something happening). However guidance is needed
Green said, and this falls into two categories:‘best practice’ and ‘first principles’.
Best practice is defined as being what is recognised as satisfying the law, although
event report special e
4. 31
feature article waterline | THE JOURNAL OF THE WATER MANAGEMENT SOCIETY
this may not always be enough and a legal judgement is based on what is relevant.
“But there may be [an appropriate] British Standard, [in which case] it would be hard
to argue that it is sufficient to do something that doesn’t meet a British Standard.”
It would be necessary to judge how much of the document should be applied to
particular circumstances so “you’re looking at proportionality v. relevance.” However,
where this guidance is not available it is necessary to go back to first principles, i.e.
directly defining consequences and solutions in relation to problems.
Green also outlined a cost benefit analysis for reasonably practicable expenditure for
prevention of potential ‘harm’.
He presented the HSE’s formula for calculating the ‘cost of risk.’This gives as an
example a chemical plant that, if it were to explode, would cause £9,300-worth of
‘harm’ in terms of fatalities and injuries using the values given in Table 2.The rate of
likelihood for this happening has been analysed at 1 in 100,000 (10-5
) per year. So it
would be reasonably practicable to spend around £93,000 (£9,300 x 10) to eliminate
the risk of explosion (see Table 3).3
Table 2. 2003 values for injury (HSE)
• Death £1,336,800
• Permanent incapacity £207,200
• Permanent incapacitatng illness £193,100
• Serious injury £20,500k
• Other ill health £2300 + £180 /day off work
• Minor (Lees than a week off) £530
• Cuts, bruises etc £300
Table 3. Calculations for amount of ‘risk’ per year for plant explosion
Fatalities 20 £1.336,800 x1x10-5
x25yrs =6684
Permanent injuries 40 £207,200 x1x10-5
x25yrs =2072
Serious injuries 100 £20,500 x1x10-5
x25yrs =512
Slight injuries 200 £300 x1x10-5
x25yrs =15
Total benefits =£9,283
PD 855468
A detailed discussion on flushing from independent water management consultant
Graham Thompson focused on Published Document (PD) 855468, the latest guidance
on the flushing and disinfection of services supplying water for domestic use within
buildings and their curtilages (Table 4). Dealing specifically with hot and cold water
systems and excluding closed systems, which already have their own guidance,
the new document separates cleaning and flushing guidance from BS 8558, with
BS8558:2015 carrying less information on flushing.While PD 855468 is not a
specification or code of practice at present, it is eventually likely to be developed into
some form of British Standard.
Graham has 25 years’ experience in the water treatment industry and has been
involved in the redrafting of HSG274 and several BSI documents. He noted that the
new document covers working to an operational plan including health and safety, risk
assessments and method statements, including considering neutralisers, and backs
the need for a schematic diagram when cleaning and disinfecting water systems to
make it clear from which outlets chlorine might emerge.
Thompson described how the sections that deal with new builds and alterations
introduce two types of flushing: cleansing flushes to remove debris, organic debris,
corrosion, disinfection residuals etc; and hygiene flushes to draw off water for the
avoidance of stagnation.The document notes that after any cleaning or any remedial
works a system should be up and running within 30 days, otherwise further flushing
may be needed to prevent stagnation.Thompson emphasised that the document
consistently encourages the importance of keeping water moving, even during early
stages of commissioning and building of projects.
Homing in on the question of the costs of flushing and how water use can affect
profits for service providers,Thompson put forward his view that at a cost of £2-3/
m3
flushing is worthwhile to avoid £100,000s in remedial works. While regulators
such as the DWI (drinking water inspectorate) promote avoidance of water wastage,
Thompson’s take on sustainability is that flushing is not a waste of water and that
weekly flushing of under used outlets is essential.However, not all of the audience
agreed. Participants in the subsequent question and answer session commented that
Table 4. Scope of PD 855468
a) residues of construction are adequately flushed from water
distribution systems;
b) appropriate water quality is achieved;
c) appropriate disinfectants and processes are used;
d) construction debris and dust are removed;
e) risk of corrosion and damage to fixtures, fittings and sensitive plant is
minimised;
f) adequate records of cleaning are produced;
g) stagnation is avoided or managed; and
h) appropriate tools and personnel are deployed for the relevant tasks.
The guidance applies to:
1) initial commissioning of new or extended systems;
2) maintenance of existing systems;
3) alteration of existing systems;
4) water quality management prior to occupation or as a result of low /
no occupancy or usage; and
5) (remedial) response to microbiological problems is identified.
some regular flushing as part of LP control regimes could be seen as a “complete
waste of water.”
On disinfection,Thompson stressed the importance of cleaning prior to disinfection,
particularly of tanks, noting that this is covered in some detail by the document.
PD 855468 puts forward chlorine-based products as the ‘example disinfectant,’ to
be used at 50ppm, but “other disinfectants may be used where they are shown to be
effective”, although they must appear in the list of products approved by the DWI for
use in public water supplies. However, the DWI requires the use of BS EN-compliant
products where it has provided acceptance criteria; chlorine requirements fall under
a BS EN standard. DWI requirements for water quality are based wholly on water
being safe and wholesome to drink – it does not imply fitness for purpose of biocides.
However, PD 855468 stresses that the “intended application [of a disinfectant]
should take into account the type of system and user profile, the specified
concentration levels and contact period.”
Thompson commented that in future the biocidal products regulations (BPR) are
likely to take over in defining what substances can be used and many products are
currently undergoing the approval process.
PD 855468 also covers:
pH considerations for dosing with sodium hypochlorite – the document suggests that
pH correction is replaced by working on a pH, time/concentration basis;
Residual disinfection – it proposes leaving in some residual chlorine, at
0.5 mg/L - 0.1 mg/L free chlorine, with no over-dosing of neutralising agents, which
would removing all oncoming chlorine.
Getting consent for discharging effluent – is a licence required?
Sampling
Record keeping responsibilities
References
1] HSE:“Reducing risks, protecting people”, 2001.
2] HSE:“Principles and guidelines to assist HSE in its judgements that duty-holders
have reduced risk as low as reasonably practicable,”
www.hse.gov.uk/risk/theory/alarp3.htm
3] HSE: Cost Benefit Analysis (CBA) checklist,
www.hse.gov.uk/risk/theory/alarpcheck.htm
* If you would like to become more involved with BSI, contact:
jessy.mathew@bsigroup.com, tel: 0208 996 7838 or visit:
www.shop.bsigroup.com/upload/forms/newsletter-signup.html
LOOK OUT FOR PART 2 OF THIS EVENT REPORT IN THE
NEXT ISSUE OF WATERLINE.
Susan Pearson BSc (susan@wordways.co.uk) is a freelance journalist and
communications consultant specialising in medicine and the environment.
Originally published in waterline Autumn 2016
