Keith Pearce – The Katmal Limited Blog

Derivation of Estimates of the Proportion of the Population in or Able to Reach a Building

This article has been largely written by AI during a conversation lasting about an hour. It seems to me to make sense and the conclusions appear sound. But it for you, the reader, to judge.

1 Purpose

This article describes the basis for the estimates used for the proportion of four population groups — baby/pre-school child, school-age child, adult and elderly person — who would, at different times of day, either already be within a building or be able to reach a substantial building within a specified period.

The estimates were developed for emergency-planning purposes, particularly circumstances in which rapid sheltering may be advised following an atmospheric release. They are derived planning estimates rather than directly observed population statistics. No UK dataset has been identified that directly records the proportion of the population that is, at a particular time, within 5 or 15 minutes of a suitable building.

The estimates therefore combine evidence on:

time spent at home and undertaking different activities;
travel and walking;
age-dependent travel behaviour;
children’s outdoor activity;
outdoor occupations; and
the accessibility of open and green spaces.

The resulting estimates are reproduced in Table 1.

Table 1. Estimated population location relative to accessible substantial buildings

Age group	Period	Already inside	Outside but shelter ≤5 min	Shelter 5–15 min	>15 min from shelter	Shelter ≤15 min
Baby/pre-school	Night	99%	0.5%	0.3%	0.2%	99.8%
	Working day	94%	4%	1.5%	0.5%	99.5%
	Evening	96%	2.5%	1.0%	0.5%	99.5%
	Weekend day	92%	5%	2%	1%	99%
Child	Night	99%	0.5%	0.3%	0.2%	99.8%
	School day	94%	4%	1.5%	0.5%	99.5%
	Evening	91%	5%	2.5%	1.5%	98.5%
	Weekend day	85%	8%	4%	3%	97%
Adult	Night	98%	1%	0.5%	0.5%	99.5%
	Working day	86%	7%	4%	3%	97%
	Evening	90%	5%	3%	2%	98%
	Weekend day	84%	8%	5%	3%	97%
Elderly (65+)	Night	99%	0.5%	0.3%	0.2%	99.8%
	Weekday day	93%	4%	2%	1%	99%
	Evening	96%	2%	1.5%	0.5%	99.5%
	Weekend day	91%	5%	2.5%	1.5%	98.5%

Percentages have been rounded and should not be interpreted as having the statistical precision implied by the individual values.

2 Definition of the location categories

For this assessment a substantial building means a normally occupied or occupiable enclosed building that could provide materially greater protection from an airborne release than remaining outdoors. Houses, schools, offices, shops, public buildings and substantial industrial or commercial premises would normally qualify. Open shelters, lightweight open-sided structures and vehicles have not been assumed to be equivalent to substantial buildings.

Four states were considered:

Already inside: the person is already within a substantial building.

Shelter within 5 minutes: the person is outside but is in a location from which a substantial building could reasonably be entered within approximately five minutes.

Shelter within 5–15 minutes: access is possible but is not immediate.

More than 15 minutes from shelter: the person is in a location or undertaking an activity for which access to a substantial building within approximately 15 minutes cannot reasonably be assumed.

The assessment is consequently not an estimate simply of the fraction of people who are outdoors. This distinction is important. A person walking along an urban street, standing in a school playground or working outside a commercial building is outdoors but may be only seconds or minutes from a substantial building. Such a person is materially different, for emergency-planning purposes, from a hill walker, agricultural worker in a remote field or person on an isolated beach.

3 Adult time-use evidence

The principal evidence concerning the distribution of adult activity through the day was the ONS Time use in the UK: 23 September to 1 October 2023 survey. Participants recorded their activities over complete 24-hour periods. Each participant was allocated one weekday and one weekend diary day. Main activities were recorded in 10-minute periods. The survey therefore provides a useful empirical basis for distinguishing weekday and weekend behaviour and the major components of the day, including sleep/rest, work, household activity, leisure and travel.

The survey does not, however, provide a direct measure of distance or travel time to a suitable building. Time-use evidence was therefore used primarily to constrain the fraction likely to be at home, at work or undertaking other activities, rather than to determine the 5- and 15-minute categories directly.

The very high night-time indoor fractions in Table X.1 follow principally from the dominance of sleep/rest and residential activity during the night. A small residual outdoor fraction was retained to represent night workers, travellers, social/leisure activity and other exceptional circumstances.

Adults were assigned the lowest daytime indoor fraction because this group contains most commuters, outdoor workers and people undertaking travel, shopping, recreation and other activities away from home.

4 Travel

Travel represents one of the principal reasons why a person may not be inside a building at a randomly selected time. The Department for Transport National Travel Survey 2024 (NTS) was therefore used as a second principal evidence source.

The NTS shows substantial travel activity across the population and permits differentiation by age, journey purpose and mode. It was used to constrain the amount of time that could plausibly be assigned to the outdoor and travelling categories.

Travel was not treated as synonymous with inability to shelter. This is an important methodological assumption.

Much travel takes place within built-up areas or between buildings. Similarly, a walking trip does not imply that the pedestrian is remote from shelter. A person walking through a town centre may be outside for an appreciable period while remaining continuously within a minute or two of shops, offices and other buildings.

Consequently, only a fraction of travel activity was allocated to the 5–15-minute category and a still smaller fraction to the >15-minute category. This is a judgement-based allocation rather than an NTS statistic.

5 Children

The principal additional source used for children was the ONS analysis Children’s engagement with the outdoors and sports activities, UK: 2014 to 2015, derived from UK time-use data.

Children aged 8–15 spent an average of 16 minutes per day in parks, countryside, seaside, beach or coastal locations. The corresponding daily participation rate was 12.2%. ONS also found higher average time in these locations at weekends than during weekdays, although the reported difference was not statistically significant.

This evidence was particularly useful because it prevents all children’s leisure or sporting activity from being classified as genuinely remote outdoor activity. Sports and active leisure include activities undertaken indoors and activities undertaken immediately adjacent to buildings.

The child estimates were therefore constructed on the following basis:

night-time occupancy was assumed to be overwhelmingly residential;
school-day occupancy was assumed to be dominated by home and school, both providing immediate building access;
the outdoor fraction was increased during evenings; and
the largest outdoor and remote fraction was assigned to weekend daytime, reflecting greater opportunity for outdoor recreation, sport and countryside activity.

This produced an estimated 3% >15 minutes from a substantial building during weekend daytime, compared with approximately 0.5% during the school day.

The distinction is deliberately conservative because even participation in a park, countryside or coastal activity does not demonstrate that the participant is more than 15 minutes from a building.

6 Babies and pre-school children

There is less direct activity-location evidence for babies and very young children. Their estimates therefore have greater inferential content.

The principal assumption was that babies and pre-school children spend a greater proportion of their time either at home or in childcare, nursery, retail, hospitality or other locations containing buildings. They are also normally accompanied when travelling or undertaking outdoor activity.

A smaller genuinely remote fraction than for school-age children was consequently assigned.

Weekend daytime was again assigned the largest outdoor component, giving an estimated 1% >15 minutes from a building. The estimate is intended to encompass family countryside recreation, beaches, parks and other activities away from buildings.

No claim is made that the 1% value has been directly measured.

7 Elderly population

Older people were assigned high building-accessibility fractions because employment and commuting become progressively less important with age and a greater proportion of activity is residential.

The NTS age breakdown was used qualitatively in making this judgement because it demonstrates substantial changes in journey purpose and mode with age. It also prevents the erroneous assumption that elderly people are almost continuously at home: shopping, personal business, social activity and recreational walking remain important activities amongst older groups.

Accordingly, the estimates allow an appreciable daytime outdoor/travelling fraction while retaining a comparatively small >15-minute fraction. The estimated latter fraction ranges from approximately 0.2% at night to 1–1.5% during daytime/weekend periods.

8 Outdoor occupations

Outdoor employment was specifically considered because it could otherwise result in an underestimate of the adult weekday exposed population.

HSE identifies occupations involving significant outdoor exposure including farm workers, construction workers, market gardeners, outdoor-activity workers and some public-service workers.

ONS also provides Annual Population Survey employment estimates at four-digit occupational classification and four-digit industry level, including breakdowns by age and country. This confirms that sufficiently detailed employment data exist to identify occupational groups with a significant outdoor component.

Outdoor employment was nevertheless not equated with remoteness from buildings. Conceptually, the contribution from an occupation was considered as:

occupational prevalence × fraction of working time outdoors × fraction of outdoor working time remote from a suitable building.

For example, agricultural and forestry work can place workers appreciable distances from buildings and was therefore regarded as contributing disproportionately to the >15-minute category.

Construction workers may also spend a substantial fraction of their working day outdoors, but construction sites frequently contain completed or partly completed buildings, site offices, welfare accommodation and adjacent development. Their probability of being outdoors is therefore substantially greater than their probability of being more than 15 minutes from any usable building.

This distinction was one reason why a relatively large outdoor component could coexist with the comparatively small 3% adult weekday >15-minute estimate.

9 Open-space accessibility

A further plausibility check was provided by Defra’s 2026 Access to green and blue space in England statistics.

Defra defines its “15-minute commitment” in terms of access by walking route to specified green/blue spaces. It reports that 80% of households in England have access to at least one qualifying green or blue space within a 15-minute walk, increasing to 91% for rural households and decreasing to 78% for urban households.

These statistics cannot simply be inverted to calculate distance from a building. They nevertheless provide a useful spatial plausibility check.

In particular, they demonstrate that a large amount of access to parks, paths and other outdoor space occurs directly from the built environment. Consequently, categorising everyone engaged in outdoor recreation as being remote from buildings would substantially overstate the population unable to shelter rapidly.

The Defra evidence was therefore used qualitatively to constrain, rather than directly calculate, the >15-minute fractions.

10 Construction of the estimates

The entries in Table 1 were produced sequentially.

First, a central estimate was made of the fraction already within buildings, using the time-of-day activity pattern appropriate to each age group.

Second, the residual outdoor/travelling population was divided between locations expected to have immediate building accessibility and locations involving progressively greater separation from buildings.

Third, NTS travel evidence was used to check that the outdoor/travelling fraction was compatible with observed levels of travel.

Fourth, the child estimates were checked against the ONS outdoor-activity evidence.

Fifth, the adult weekday estimate was increased relative to the other groups to accommodate outdoor occupations and work-related travel.

Sixth, the weekend child and adult fractions were increased to represent outdoor recreation.

Finally, the estimates were checked against the Defra spatial-access evidence to ensure that outdoor recreation had not implicitly been treated as synonymous with remoteness from buildings.

The method is therefore best described as a constrained expert-judgement model rather than a statistical derivation.

11 Uncertainty and conservatism

There are two different types of uncertainty in Table 1.

The first concerns the fraction already inside a building. This is reasonably well constrained by time-use, employment and travel evidence, although there remains uncertainty concerning the precise definition of indoor activity.

The second, and substantially larger, uncertainty concerns the division of the outdoor population between the ≤5-minute, 5–15-minute and >15-minute categories. No identified national survey measures these quantities directly.

Consequently, values such as:

Adult, working day: 86% inside, 7% within 5 minutes, 4% within 5–15 minutes and 3% beyond 15 minutes

should not be interpreted as measurements with percentage-point precision. A more appropriate interpretation is that the evidence indicates an indoor fraction of approximately 85–90%, while expert judgement suggests that most of the residual population remains close to buildings and only a few percent is likely to be genuinely remote.

For this reason, where the purpose is emergency-planning modelling rather than demographic analysis, a simpler assumption is preferable.

The detailed analysis indicates central estimates of approximately 97–99+% of the population able to obtain access to a substantial building within 15 minutes, depending upon age and time of day.

A generic assumption of:

95% able to obtain substantial shelter within 15 minutes

was therefore proposed as a deliberately conservative planning value.

This 95% value is not an ONS, DfT, HSE or Defra statistic. It is a modelling assumption derived from the evidence described above and incorporates an allowance for uncertainty.

12 Limitations

The estimates are intended to characterise a generic UK population. They should not automatically be applied to a particular site without considering local circumstances.

The proportion unable to reach shelter rapidly could be higher around locations characterised by extensive:

agricultural land;
moorland or mountains;
beaches and coastline;
large parks or recreational areas;
forestry;
reservoirs and other water-based recreation;
outdoor industrial activity; or
transport infrastructure remote from occupied buildings.

Conversely, the generic estimates are likely to be conservative in densely developed urban areas where people outdoors are generally close to multiple buildings.

The analysis also considers physical access to a building, rather than whether the building is open to the public, whether access would be permitted during an emergency, or the degree of radiological protection actually afforded by the building. These issues would require separate consideration.

13 References

Office for National Statistics (2023). Time use in the UK: 23 September to 1 October 2023. Experimental statistics. The survey used full 24-hour diaries, with participants allocated one weekday and one weekend diary day.
ONS — Time use in the UK
Office for National Statistics. Children’s engagement with the outdoors and sports activities, UK: 2014 to 2015. Includes time and participation rates for children aged 8–15 in parks, countryside and coastal locations.
ONS — Children’s engagement with the outdoors and sports activities
Department for Transport (2025). National Travel Survey 2024. Used for travel frequency, duration, purpose, mode and age-dependent travel behaviour.
Health and Safety Executive. Outdoor workers and sun exposure. Identifies occupational groups for whom work involves extended periods outdoors, including agricultural and construction workers.
HSE — Outdoor workers and sun exposure
Office for National Statistics (2026). Employment by detailed occupation and industry, by sex, age group and country, 2024 and 2025. Annual Population Survey estimates at four-digit occupational and industry classification.
ONS — Employment by detailed occupation and industry
Department for Environment, Food & Rural Affairs (2026). Access to green and blue space in England. Official statistics in development; provides walking-route-based measures of access to qualifying open spaces, including the 15-minute commitment.
Defra — Access to green and blue space in England

Overall evidential status

The source evidence supports the proposition that most people are either indoors or undertaking activities in locations from which buildings are readily accessible. It does not directly measure building accessibility.

Accordingly, Table 1 should be described as derived planning estimates informed by UK time-use, travel, employment and spatial-access statistics, rather than as measured population fractions. The greatest uncertainty attaches to the allocation of people who are outdoors between the ≤5-minute, 5–15-minute and >15-minute categories.

Book Review – Practical guidance for mental health and psychosocial support in radiological and nuclear emergencies

IOP Publishing have just published a Book Review of mine in Journal of Radiation Protection.

“Review of the 2024 NEA report: practical guidance for mental health and psychosocial support in radiological and nuclear emergencies”

I think that this NEA report provides a useful contribution to the protective actions discussion and should be widely read within the industry, relevant local authorities, government bodies and regulators.

To whet their appetite they could start with my review.

The NEA Small Modular Reactor Dashboard: Second Edition

The NEA Small Modular Reactor (SMR) Dashboard offers a comprehensive assessment of global progress in SMR development, focusing on seven key dimensions: technical readiness, licensing, siting, financing, supply chain, engagement, and fuel.

The second edition of the Dashboard evaluates 56 SMR designs worldwide, highlighting significant advancements toward deployment and commercialization in both NEA and non-NEA member countries.

SMRs are characterized by their smaller size, typically producing up to 300 MWe, with some designs as small as 1-10 MWe. They are designed for modular manufacturing, factory production, portability, and scalability, offering potential benefits in safety, operational flexibility, economics, and waste management.

The Dashboard reveals substantial progress in SMR deployment, with a subset of designs in advanced stages of commercialization. The first SMRs are expected to be operational within this decade, with accelerated global deployment anticipated in the 2030s.

The report also shows what a crowded market the SMR world has become.

For more detailed information, the full report is available on the OECD-NEA website at https://www.oecd-nea.org/jcms/pl_90816/the-nea-small-modular-reactor-dashboard-second-edition

ONR and the Safety Culture

ONR’s new document Safety Culture: Definition and Model (2024)[1] “introduces the Office for Nuclear Regulation’s (ONR) definition and model of safety culture. Its purpose is to create a collective understanding of safety culture across Great Britain’s nuclear industry to improve organisational learning, and to provide ONR with a simple and straightforward way to engage with those that we regulate on this important topic”.

Safety culture has been defined as that assembly of characteristics and attitudes in organizations and individuals which establishes that, as an overriding priority, nuclear plant safety issues receive the attention warranted by their significance (INSAG-4, 1994).

The NISCI is a research-driven tool[2] that evaluates safety culture across nuclear organisations. Its foundation lies in the IAEA’s Harmonised Safety Culture Model, adapted to the specific needs of Great Britain’s nuclear sector through input from all UK licensees. It focuses on identifying and improving underlying attitudes, behaviours, and values related to safety.

It presents a theoretical model based on the work of Schein (1985) and others which has 6 dimensions and 16 sub-dimensions. “The model differentiates between the underlying foundations of culture, in terms of policies, processes, training, and communications, which organisations have in place to support the safety culture, and the elements of the culture which reflect the underlying values, beliefs, and attitudes towards safety”.

The 6 dimensions are:

Reporting – Focused on fostering a sense of safety, confidence, and informed compliance.
Senior Leadership – Encompassing communication, consistency, and openness about safety.
Line Management – Addressing communication, consistency, and receptiveness at the managerial level.
Challenge – Encouraging a questioning attitude and attentiveness to weak signals.
Accountability – Promoting a “just culture” where accountability is constructive.
Immersion – Relating to employees feeling valued and engaged in safety efforts.

For each of the 6 dimensions the ONR provides a few “attributes” (or “sub-dimensions) that it looks for and the summary of what bad and what good looks like.

In this the mechanism is rather like the IAEA 2020 Working Document “A Harmonized Safety Culture Model”.[3] This gives us a definition of ‘safety’ is “the protection of people and the environment against radiation risks, and the safety of facilities and activities that give rise to radiation risks” (which seems excessively focussed on radiation whereas, I suspect, more people are hurt by slips, trips and falls).

The research paper reports the results of a consultation involving 3,480 workers from 15 nuclear duty holders. It concludes that the scores are high, reflecting the high standard of safety in the GB’s nuclear industry.

ONR highlights the importance of continuous improvement in these areas, advocating for clear communication, consistent leadership actions, and worker engagement to strengthen safety performance and outcomes.

I expect we will see this take life as a periodic questionnaire distribution and comparison of results from site to site and from time to time. But a strong safety culture isn’t just about compliance—it’s about fostering a proactive environment where safety is part of every decision. Tools like NISCI help organisations benchmark their performance, identify gaps, and create tailored improvement plans. This is particularly valuable in building public trust and ensuring operational excellence.

Plymouth Unexploded bomb

I listened to a very interesting talk organised by the Emergency Planning Society, a Lunchtime Learning Session – Plymouth Unexploded Ordinance Device Incident.

A 500 kg unexploded bomb from an air raid between 28^th and 29^th April 1941 was found when digging out the foundations for a house extension.

The on-call emergency responder took the initial call just before 11 am and at 13.30 the Police declared a Major Incident. An initial 214 m evacuation cordon was put in place with the National mobile phone warning system used in anger for the first time and teams from multiple organisations going door to door. The zone evolved with time.

More than 4,200 properties were evacuated involving more than 10,300 people. While many made their own arrangements more than 1000 attended Rest Centres over the three days and more than 1000 calls were received on the 24/7 helpline and 73,000 hits on the website.

The bomb was later moved and destroyed at sea. The move entailed a temporary evacuation of the area either side of the route.

Of particular interest:

A few people were reluctant to leave their homes. Major concerns seemed to be about pets (RSPCA helped) although there were some health issues to manage. These all take resources to work through.

There is a reluctance to use gyms for overnight stays. Preference is to put people up in B&Bs or hotels.

The National Emergency Notifier System worked well with the message out within 30 minutes of the decision to use it. With prepared messages this could be speeded up. Unsurprisingly the system “leaks” in that the message is received beyond the intended footprint so it is important to consider the wording of the message – not “please evacuate” but “please evacuate if you are in this area”.

The council rejigged their “when are my bins emptied” website to show the intended evacuation area in detail. Which was a quick process. Well done Council GIS team.

The area followed the REPPIR process of zigzagging along streets rather than cutting through lines of houses. Good practice.

The local football ground was used as a briefing centre for the boots on the ground.

Supply of sand was successful but not needed in the end (If bomb had been detonated in-situ it would have been surrounded by sand to manage the explosion).

Vulnerable people were identified by door knockers rather than by comparison of agency lists. This was not what the plan expected.

A very interesting talk about the day in a life of a council emergency responder and a good example of multiple agencies working together well. The response would probably not have been so successful without the careful planning and exercising that takes place.

Links

Government press release

BBC News

Sky News

Do we have to freeze as well?

Sheltering in place is thought to be an effective protective action in the case of releases of radioactive dusts and gases from nuclear sites because it reduces gamma radiation dose by a combination of shielding and distance and it reduces the inhalation dose while the airborne levels are higher outside than in. If you are going to stay in shelter for any length of time with elevated external levels it is obviously better to reduce air exchange between the inside and outside.

The UK national advice on the topic has “Key factors affecting the effectiveness of sheltering-in-place include: the air permeability of a building used for shelter; the meteorological conditions; the particle size distribution; the effectiveness/timing of opening windows and doors; and the release duration, all of which could vary significantly from one scenario to another (or even within a single scenario). Some of these factors such as meteorological conditions are time dependent, and therefore the DRF may vary as a function of time.” (PHE-CRCE-049)

Advice to the public in the UK is provided by REPPIR Prior Information leaflets and websites for those near to nuclear sites. These tend to have the advice to close doors and windows and will then say something about other steps that can be taken to reduce air exchange. Examples:
Barrow: “Switch off fans, heating systems, air conditioning and put out open fires”.
Capenhurst: “Switch off all heating systems. Ventilation fans and air conditioning systems to avoid drawing in outside air”.
Devonport: “Put out fires and boilers and shut off air conditioning units. Fans, air conditioning units, boilers, gas fires and heating systems draw in air from outside. You should switch off these things (and damp down open fires) to stop radioactive material from outside coming inside”.
EDF sites “close all outside doors and windows, switch off any ventilation or extractor fans”. [No mention of heating!]
AWE “Turn off boilers and air conditioning units and put out fires or woodburners. Fans, heating systems, boilers, gas fires and air conditioning all draw in air from outside so these should be shut down to minimise radioactive particles entering buildings”.

While the physics suggests that air exchange between the outside world and the inside of a building is affected by the temperature difference most of the historic concern, I suspect, is with systems that burn hydrocarbons in-situ and are designed to draw in air to support combustion. Not everybody uses such systems these days.

Are there forms of heating that we can use safely while in shelter – electric panel convection heaters or air source heat pump serving underfloor or ceiling mounted fan coil units that don’t obviously rely on external fresh air or do we all have to freeze while waiting for the all-clear or evacuation instructions?

NHS England Emergency Preparedness, Resilience and Response Guidance for the initial management of self-presenters from incidents involving hazardous materials.

This article is a brief synopsis of an NHS England paper looking at how it relates to nuclear licensed sites. Please refer to the original paper rather than this article if preparing plans. Katmal Limited can provide advice on planning should you require it.

https://www.england.nhs.uk/wp-content/uploads/2019/03/guidance-for-the-initial-management-of-self-presenters-from-incidents-involving-hazardous-materials.pdf

“Members of the public who may be contaminated, especially following large incidents, may leave the scene and subsequently seek assistance at a nearby healthcare facility. All healthcare facilities are required to have arrangements in place to manage self-presenting patients. These plans need to recognise that people concerned about the health impacts of a HazMat/CBRNE contamination incident, but not necessarily affected by it, may also attend healthcare facilities and other NHS sites even though they do not require treatment.”

Timely alerting – are all NHS facilities alerted to a local incident?

Planning risk assessment

“The risk assessment should also take account of the need to protect healthcare facilities, staff members and uncontaminated patients and the provision of timely and appropriate care to people self-presenting from a HazMat/CBRNE incident”. This risk assessment is likely to conclude that anyone self-presenting following an accident at a nuclear reactor site may be contaminated with fission products (other licensed sites have their own specific hazards – for example plutonium, uranium or tritium for AWE) but, actually this remains unlikely and the levels of contamination if they were to be contaminated would not be sufficient to affect the health of staff members, uncontaminated patients or other persons on site. What remains is a presentational issue. How do we assess and reassure the self-presenter and how do we maintain confidence that the facility is fit for purpose against rumour that it is badly contaminated?

The paper does not mention it but for those NHS facilities near a licensed site it would be sensible to understand the type of contamination that is possible and how it could be identified and measured on people. This is easier for sites that might release beta/gamma active materials rather than sites that might release pure alpha emitters. But either way, an understanding of how to detect and measure plausible local contaminants should be pursued and suitable instruments maintained.

“Organisations may wish to identify areas of their premises where IOR [Initial Operational Response] activities can take place. This would include access to clean running water and be considerate of patient modesty. Such areas could be marked with zones for patients to disrobe and then move to, making communication easier”.

Ideally the facility would be able to move the self-presenters to a remote area where they can be processed without the potential to contaminate busy areas of the facility. Initial screening might be by questioning where the person was and what they were doing during plume transit.

“An incident of this nature has the potential to be disruptive and may result in the affected premises being compromised for a period of time. The plan will need to link to the organisation’s business continuity arrangements to mitigate this.”

Section 3.6 of the paper reviews the potential psycho-social impacts of the event stating that the public are likely to be orderly, will respond better in a well planned and executed response with clear information, efficient, polite and caring handling of self-presenters including respected the need for privacy and modesty during decontamination. It is important to plan and train to get this aspect of the response right.

“Available evidence suggests public behaviour will be orderly and there will be no panic.”

“These arrangements and the Remove, Remove, Remove model do not require staff members to wear specialist protective equipment[1] nor does it require specialist decontamination equipment for the patient to use. Instead the model utilises any absorbent material such as blue roll or paper towels which can be retrieved from most building’s toilets or kitchen facilities”.

Lock-down procedures might be required to control access and egress to the facility to minimise confusion and the spread of contamination. “It should be noted, however, that healthcare organisations cannot physically prevent people from leaving their premises (even if the hazard or threat is outside the building which is locked down)”.

The NHS has a STEPS 1-2-3 protocol:

“The Emergency Services use the STEPS 1-2-3 plus process as a recognition and risk assessment tool. If one incapacitated patient is encountered with unexplained symptoms then they are treated using NHS universal precautions. If two incapacitated patients are encountered together with unexplained symptoms they are treated with caution and a high index of suspicion of contamination using NHS universal precautions. When three or more incapacitated patients are encountered together with unexplained symptoms the staff withdraw to a safe distance and call for specialist resources and advice. At the same time the plus element indicates the instigation of IOR.”

This is very unlikely to be triggered for a nuclear accident at a licensed site as the dose rates are likely to be too low to trigger symptoms. It could be triggered if a powerful source is left in a public space (See Cochabamba bus incident 2002) or if a powerful source is dismantled and distributed among a population (See Goiania orphan source incident 1985).

The remove, remove, remove Initial Operational Response then comes into play.

Tell those affected to:

Remove themselves … from the immediate area to avoid exposing others. Fresh air is important.
Remove outer clothing …
- Avoiding pulling clothes over head if possible;
- Do not eat, drink or smoke
- Do not pull off clothing stuck to skin
Remove the substance …. from the skin using a dry absorbent material to either soak up or brush it off.

Again, it is unlikely that skin will be itchy or painful as a result of radioactive contamination. Care should be taken not to break the skin and allow contaminants a route into the body.

Under the remove themselves banner it is suggested that the self-presenters should be isolated from other patients and staff members in a safe area, preferably outside. Continuous clear communication would be key so that the worried person does not feel abandoned.

The advice for removing outer clothing (which is expected to remove most of the contamination) suggests that “Undressing should be systematic to avoid transferring any contamination from clothing to the skin”. It recommends cutting clothes off rather than pulling them over the head. The important thing is to avoid touching the outer surface, particularly avoiding the outer surface coming into contact with the mouth, nose or eyes.

Modesty and warmth may become an issue when asking members of the public to disrobe outside.

Removed clothing should be bagged and labelled but this process should not be allowed to slow the undressing process unduly.

Dry decontamination, blotting and lightly rubbing skin with any dry absorbent material such as paper tissue, clean cloth etc is the preferred for of decontamination.

Hair may need careful wet decontamination. In the meantime potentially contaminated hair should be covered and away from the face.

If there is an incident a dynamic risk assessment would be expected from those in charge.

“When conducting a dynamic risk assessment there are five principal stages to be followed:

Stage 1 – Identify the hazard

The first step is to look for hazards. Consider the location that the activity or process is carried out and check for potential dangers. Concentrate on anything with the potential to cause serious harm to employees, members of the public and the patient(s).

Stage 2 – Decide who might be harmed and how

Decide who and how many might be at risk

Stage 3 – Evaluate the risks and identify suitable and sufficient control measures

Implement the Remove Remove Remove procedures

Stage 4 – Record and implement findings

The findings of the risk assessment must be brought to the attention of those at risk to harm and appropriate training and instruction given on the implementation of the control measures.

Decide who and how many may be at risk; is it those undertaking the activity or may it also affect members of the public and staff.

Stage 5 – Review the assessment

All risk assessments should be reviewed at a frequency proportional to the risk.”

Section 5 states that there might ne a requirement to seek specialist advice. This may come from UKHSA or the operator of the facility that is the source of the issue.

There is more discussion about PPE (Section 6) and Quarantine (Section 7) and a larger section on Recovery (Section 8).

This is a refreshingly short and focused advice sheet with sensible sounding advice.

[1] Direct physical contact with the patient(s) should be avoided.

Dalton Seminar Series: SMRs and Beyond: A Panel Discussion

15^th March 2023 (Attended remotely)

This event is available to view on-line.

Speakers:

Daisy Ray, Innovation Programme Lead – Advanced Nuclear, Department for Energy Security and Net Zero.
Juan Matthews, Visiting Professor in Nuclear Energy Technology, Dalton Nuclear Institute.
Tom Purnell, Business Development Director, Nuclear AMRC.
Robert Exley, Superintending Inspector, ONR.
Mike Crawforth, Business Development Manager, Rolls Royce.

My enjoyment of this meeting was slightly reduced by the difficulty in hearing some of the speakers, notably the Chair.

The first speaker Mike Crawforth, RR stated that his Company is trying to be at the forefront of deploying nuclear solutions. He was concerned about the day’s budget and whether Government money is available for development (RR spend a lot of time demanding state handouts). No worries about the size of market, just de-risking the first build. (Actually, while they seem to be making steady progress they are quickly falling behind their international competitors particularly Russia, China and Canada).

They admit that they need to prove that they can drive down the costs by mass production (this needs a mass market) and by modularisation. Need to not over promise (but rather cocksure about the lack of technical risk). They are interested in district heat (which has a poor history in the UK) and synthetic fuels (which are important to RR’s other industries).

Second Speaker. Tom Purnell, AMRC. Lots happening in the market and internationally. AUKUS will take up resource as will British submarine build and power station decommissioning. Government investment decisions will be important. The declaration of nuclear as “clean energy” is good news. Quite a lot of positivity. Need confidence to invest in new processes such as new PV welding processes which reduce the weld time from 10 days to 2 hours which saves CO₂, and programme time/costs.

Prof Juan Matthews. Worked on SIR in 1989 but could not build it because the price of gas was so low. He pointed out that only 20% of energy used in the UK is electricity so there is more market for nuclear in heating and transport.

He thinks we need dedicated SMRs for hydrogen production (for which we’ll need a market for hydrogen which does seem to be developing), thermal energy storage (to cope with intermittency of renewables), and high temperature reactors for industrial use and more efficient hydrogen production.

Robert Exley (ONR) leading GDR of RR-SMR. Explained roles of the three main regulators (planning Inspectorate – impact on community) Environment Agency (Discharges etc), ONR (nuclear and conventional safety, security, safeguards) and the role of the 36 site license conditions.

Spoke a bit about the Generic Design Assessment (which has approved four types of reactor, only one of which has proceeded to construction so could be seen as a poor use of resource).

Dr Ray spoke about AUKAS as a showcase for British Nuclear and suggested that a nuclear renaissance was due or underway. The ambition of her department is a demo reactor by the end of the 2030s.

Lots of thought being put into how AMRs might be used in industry (I’m sceptical of the model that has a foundry, or whatever, having its own reactor. Too many eggs in one basket and issues about load following that are only partly answered by molten salt energy stores. If Companies find it easier to outsource their office cleaning, why would they take running a nuclear reactor in-house? It does make some sense in the far north which is why Russia and Canada are more likely to progress the model than the UK ). Much better to have companies that sell electricity on to the grid and customers who take energy off the grid. But maybe I’m old fashioned).

She mentioned the potential issue with the availability of skilled workforce in the future with so many branches of the industry dreaming of good times ahead. Some good work with Universities and Colleges heading in the right direction.

When asked about the technical risks facing the RR SMR Mike Crawforth was confident (over confident? – remember Admiral Rickover https://whatisnuclear.com/rickover.html) that there weren’t really any and the project would stand or fall based on funding, market and manufacturing and assembly innovation. The current cost estimates are made assuming boring technology and boring manufacture in the expectation that innovation will drive costs down over the build time of the fleet.

There was a suggestion that we need bigger reactors than the current RR-SMR design opening the possibility of the initial design being very conservative but later iterations pushing the boundaries more.

There was a question about fuel supplies availability given a worldwide surge in nuclear and the international situation. Confidence was expressed about the near future but the need for a closed cycle was mentioned.

There was a brief discussion about Countries working together to assess and approve the designs of reactors. The ONR representative thought it possible but the UK would retain the final say on reactor designs for the UK. (I’ll only believe international licensing when I see it).

There was a brief discussion about engaging with local communities where a reactor is suggested. Seems to be considered a good idea.

It is a pity that a question about whether or not ONR would license a reactor design and admit that no off-site plan was required was not answered as we ran out of time.

This was an interesting collection of expertise and an interesting topic of discussion. Given that, one hour was probably too short to make the best of the assembled team and while remote attendance is far better than no attendance it does not match the experience of being there and being able to interact more strongly.

My thanks to the organisers for the invitation to the event.

My first computer generated blog

The following article was written by a guest writer, ChatGPT given the prompt “tell me about the Radiation (emergency Planning and public information) regulations 2019”. It is not at all bad. This technology is going to change the way we work!

The Radiation (Emergency Preparedness and Public Information) Regulations 2019 (REPPIR 2019) are a set of regulations issued by the UK government that provide guidance on emergency preparedness and response in the event of a radiation emergency.

The purpose of these regulations is to ensure that there is a coordinated and effective response to a radiation emergency in the UK. They apply to a range of activities involving radioactive substances, including nuclear power plants, hospitals, and research facilities that use radioactive materials.

Under the REPPIR 2019 regulations, operators of sites that use radioactive materials must conduct regular assessments of the risks associated with their activities, and they must develop and maintain emergency plans that specify how they will respond to a radiation emergency. These plans must be regularly reviewed and tested to ensure that they are effective and up to date.

The regulations also require operators of sites that use radioactive materials to provide public information about the risks associated with their activities, as well as information on how to respond in the event of an emergency. This information must be easily accessible to the public and must be regularly reviewed and updated.

In addition, the regulations establish a framework for coordination and cooperation between the various agencies and organizations involved in responding to a radiation emergency, including the emergency services, local authorities, and national government agencies.

The REPPIR 2019 regulations build on the previous Radiation (Emergency Preparedness and Public Information) Regulations 2001, and they reflect changes in the technology and practices associated with the use of radioactive materials.

Overall, the Radiation (Emergency Preparedness and Public Information) Regulations 2019 represent an important step forward in ensuring that the UK is prepared to respond effectively to a radiation emergency, and that the public is adequately informed and protected in the event of such an emergency.

The UK Government Resilience Framework December 2022

This blog gives my impressions of a potentially important Government publication looking at the resilience of the UK (well actually the resilience of England and Wales). The report being discussed can be found at https://www.gov.uk//government/publications/the-uk-government-resilience-framework

A policy paper that predates this report stated that “The National Resilience Strategy will specifically consider the roles and responsibilities of CNI owners and operators to ensure high levels of resilience across our most essential sectors. The strategy will also consider how to integrate the roles of CNI owners and operators within a wider framework that also incorporates all levels of government, the wider private sectors, civil society and the public”.

It also said that:

“Much of what is needed is already in place, but improvements can still be made:

government should publish a full set of resilience standards every five years, following advice from regulators, alongside an assessment of any changes needed to deliver them;
infrastructure operators should carry out regular and proportionate stress tests, overseen by regulators, to ensure their systems and services can meet government’s resilience standards, and take actions to address any vulnerabilities;
infrastructure operators should develop and maintain long term resilience strategies, and regulators should ensure their determinations in future price reviews are consistent with meeting resilience standards in the short and long term”.

It recommended that government should introduce a requirement for Secretaries of State to publish (among other things) “clear, proportionate and realistic standards every five years for the resilience of energy, water, digital, road and rail services”. These seem more about the continuity of service (business continuity) with targets “which cover 12 key service areas, including supply restoration, connections and voltage quality” rather than the protection of the public so may not have a great effect on emergency planning as I know it.

It is claimed that “Setting agreed standards is key to effective assurance regimes that ensure that the UK’s most critical systems and organisations are resilient across a broad range of risks, that operators, regulators and stakeholders have confidence in that assurance and have clarity on what further resilience improvements are necessary and desirable” whereas I would argue that correctly identifying the level of preparation that is sensible and then meeting and policing appropriate standards make the difference not setting standards alone, but then I’m not a Civil Servant.

While talking about a “National Strategy”, written and managed by the UK Government, the paper admits that it has no control over the actions of the devolved administrations and seems to suggest that this will continue.

[Para 64] “The UK Government remains fully committed to working closely with the devolved administrations to ensure integration of respective approaches, share best practice and learning, and ensure strong cross-border collaboration – delivering on our duty to protect citizens in every part of the UK. The devolved administrations have their own established and effective local resilience partnerships, and these will not be impacted by the planned strengthening of English LRFs”.

Given that this did not work during the Covid response, what happened to learning from experience?

Early in the resilience framework report it states that “This framework focuses on the foundational building blocks of resilience, setting out the plan to 2030 to strengthen the frameworks, systems and capabilities which underpin the UK’s resilience to all civil contingencies risks”. It is seen as a “long term commitment to systematic changes” [Para 3].

The introduction to this current paper refers to the war in Ukraine, Covid, climate change and “cyber challenges” which makes a change from flu, flood, animal disease, terrorism and industrial accidents which have been the headline risks for many years. Who can remember being told that the government, local authorities and NHS were ready for a severe flu pandemic but watched it fold like a playing card castle in a hurricane when Covid, which shares many of the attributes of flu, hit the world? Apparently “Although there was an understanding of the risk of pandemic flu, treating it as a health emergency meant that there was limited planning outside of the healthcare sector”. So that’s alright then.

We are told that we now have “bold and comprehensive plans to build resilience to specific risks”, personally I’d settle for appropriate and adequate rather than bold which according to my Oxford dictionary means “confident and daring or courageous” or “audacious; impudent”. Confidence in plans too often turns to hubris. Emergency planning is a career that should be reserved for pessimists and worriers once you think that you have comprehensive plans you are on a slippery slope.

The Government’s approach to resilience is to develop a shared understanding of the civil contingencies risks we face; prevention is better than cure and resilience is a whole of society endeavour. This all sounds reasonable.

The weakness is that no matter how many committee hours we spend gazing into crystal balls life can hit us with something we hadn’t considered or something we had considered but with a slight variation that throws our plans out of the window. “No plan survives first contact with the enemy”[1]. However, plans can be flexible and plans can be exercised. Having a framework in which different disciplines work together coordinated by agreed mechanisms and sharing information and expertise should allow a better response to events. The history of the British Government response to major events has included events where a the carefully prepared plan was not used (Fukushima – initially seen as a humanitarian issue so the nuclear plan emergency plan was somewhat bypassed) and where the carefully prepared plan had fallen into disrepair (Flu/Covid where stocks of PPE had been run down on the promise of just in time acquisition and had not really followed through on consideration of the impacts).

As the paper admits “But, while prevention is a key principle, it cannot replace careful and effective management of emergencies as they occur”.

The paper talks about a new “Resilience Directorate” [para 53 and 54] but I cannot find any other mention of it on Government websites. This will work alongside COBR.

On the National Security Risk Assessment (NSRA) the report states that: “The UK Government’s ambition is to create an NSRA process which readily invites external challenge from experts, academia, industry and the international risk community. Relevant information from the NSRA, sensitivity permitting, will be openly available to the public”. This is good to hear and it hasn’t fallen too far short of that target in the past although the public facing National Risk Register has recently been dumbed down to make it “more accessible to the public” but has reduced its usefulness to the preparedness professional.

It also talks about “multiple scenarios” which is encouraging. I’ve previously found that some other countries publish a range of scenarios for each threat against which their plans are prepared and tested. I’ve always thought this good practice provided the system does not become too rigid.

The UK Government could learn from the US 2019 National Threat and Hazard Identification and Risk Assessment (THIRA) which

reports a literature review of existing government response plans and academic studies to develop a preliminary list of 59 threats and hazards.
Consulted with subject-matter experts (SMEs) and reviewed a preliminary list of threats and hazards to select nine scenarios—consisting of both natural and human-caused incidents—that would most challenge the Nation’s capabilities.
Developed a set of 29 standardized impacts, based on in-depth research and stakeholder feedback. These standardized impacts represent key metrics that emergency managers use to understand the magnitude of a disaster, such as fatalities or number of people requiring shelter.
Finalized 22 specific, quantifiable capability targets, representing the most critical and measurable elements of selected core capabilities.

These are used to develop and test plans and confirm that adequate resources, including trained personnel, are available.

Also mentioned is a National Situation Centre [paras 39 – 42] which was new to me. This can be found elsewhere on the Government websites “The National Situation Centre (SitCen) was established to bring data, analysis and insight together, boosting the government’s ability to identify, monitor and manage risks. For example, during the period of extreme heat in July, the SitCen worked with partners to identify vulnerable groups and locations, enabling responders to target support effectively”. This sounds like a useful asset. [see also job advert for Technology Head].

Under the title “Social Vulnerability” [Paras 43 – 48] the paper talks about data sharing before and during crisis and stating an aspiration to improve this that squeezes in a suggestion that additional problems meet ethnic minority and low-income groups which must be reflected in plans and preparations. See also para 32 with regard to communications to these groups and an annual survey of public perceptions of risk, resilience and preparedness.

An expressed intention is to develop a measurement of socio-economic resilience and vulnerability to “provide a snapshot of the key characteristics of local areas”. In my work with them, I have found that LRFs have a very good understanding of their area; being able to make educated guesses about how easy it would be to evacuate areas based on an impression of household size, car ownership and transport links and what proportion of the affected people might use reception centres rather than make their own arrangements for accommodation. To attempt to make this more rigorous and data based may not be easy nor cost effective although in the era of big-data it may be easier than I suspect.

The UK Government will continue to use the Lead Government Department model to guide risk ownership, but there will be further clarification of roles and responsibilities for complex risks. In addition, “Government will create a new Head of Resilience role to provide leadership for this system. This new role will guide best practice, support adherence to resilience standards, and test planning in a meaningful and proportionate way to support the LGD model”.

A commitment [para 31] is given that “The UK Government will improve its communication of risk, focussing on personalisation (for organisations and individuals) as a means to ensure that organisations and individuals have access to relevant, actionable information. We will work closely with both national and local partners to develop and deliver these messages, as well as supporting partners to develop and deliver their own communications campaigns”. Always easier said than done successfully.

The proposed Annual Statement to Parliament on civil contingencies risk and performance and any debates within the House will be one to watch.

The paper reiterates the commitment that “local level will continue to be the building block of the UK’s resilience” and to “significantly strengthen LRFs (in England)” but most of the development seems to be at central government level. Changes at LRF level seem to concentrate on accountability and “clear mechanisms for the assurance of the multi-agency activity”.

Paras 79 – 88 discuss the CCA. This reiterates the central government view that enhanced accountability combined with moving the current advisory resilience standards to a statutory footing will sort any local weaknesses. In addition, they recommend making the Met. Office a Cat 2 responder (sensible) as well as the Coal Authority (I have no view on this).

“The armed forces will continue to play a vital supporting role to the civil authorities in resilience but will not be asked to take on an enhanced role” [in para 93].

Page 33 marks the start of an Action Plan.

Para 110 talks about engaging the private sector (mainly considering CNI) and includes “Raising private sector resilience standards may mean that the UK Government asks more of some parts of the private sector, but it will provide the guidance and information on risks that organisations need in order to be able to meet the standards that the UK Government sets”. The Government providing guidance and information and then asking private industry to put significant effort into something they may not see as a benefit might be a hard sell. Industry needs to know “What’s in it for me?” Again, I hear the voice of Civil Servants living in a world of their own.

To achieve this promulgation of standards “The National Infrastructure Commission has recommended that the UK Government should publish a set of standards for energy, water, digital, road and rail services, to be reviewed and updated every five years” and the Government has committed to do this (“to create common but flexible resilience standards across CNI”) and to develop an action plan to deliver the standards[Para 114]. The CNI standards will be stress tested.

It is intended that there will be a review of the existing regulatory regimes on resilience [Para 119] and regulation may be extended to cover the highest priority sectors and risks that are currently not subject to regulation.

P.131 UK Resilience Forum (UKRF) was established in 2021. The UKRF brings together representatives from the UK Government, devolved administrations, emergency services, responder organisations, the private sector and the voluntary and community sector. This advisory board is aimed at aligning efforts across the system, strengthening relationships between partners, and informing the government’s work on its resilience commitments under the Integrated Review.

P146 “the UK Government will continue to deepen and strengthen its relationships with the VCS (Voluntary and Community Sector) in England. The capabilities of the VCS will be better understood and integrated, as appropriate, strengthening resilience at local and national level in England”.

The Department for Digital, Culture, Media and Sport is also funding the Voluntary and Community Sector Emergencies Partnership (VCSEP) in England with up to £1.5m, to 2025.

Page 49 onwards – Investment

There is a commitment that by 2030 the Government will

“Have a coordinated and prioritised approach to investment in resilience within the UK Government, informed by a shared understanding of risk.
Consider options for funding models for any future expanded responsibilities and expectations of LRFs in England.
Offer new guidance to community organisations and individual householders, to help those people to make more informed decisions about investing in their own resilience and preparedness”.

Some interesting statistics:

Where there is a risk of flooding, the Environment Agency has helped ensure homes are built in a flood safe way. Every £1 spent advising on flood risk matters in spatial planning applications has saved £12 in future flood damages.
During Storm Christoph, 49,000 properties were protected from flooding, with fewer than 1200 inundated.
Improved response arrangements ensured that a Foot-and-mouth outbreak in 2007 caused much less damage (£150 million) than the outbreak in 2001 which cost the UK around £8 billion.

There could be increased funding of LRFs. “DLUHC (Department for Levelling Up,
Housing & Communities) agreed a £22m three-year funding settlement or LRFs in England starting in the 22/23 financial year” [Para 174]. This does not commit the additional funding of LRFs to extend beyond the third year leaving the Government to “consider options for funding models for any future expanded responsibilities and expectations of LRFs” [Para 175]. The Government preference is unsurprisingly to spread the cost among responder organisations and businesses.

Page 58 onwards Skills

There is an intent to set up a UK Resilience Academy built on the Emergency Planning College to deliver new training and skills and create a professional pathway. This “will be a physical and virtual campus delivering the scoping, design and delivery of training, wider education, learning and development and exercising for resilience professionals” [Para 195].

Annex B summarises the Framework actions.

Summary

This is a comprehensive document suggesting a step change in the Government’s view of resilience. It is a surprise that it totally ignores Business Continuity Management which seems to me to be closely related to resilience in the sense it is used here and is well imbedded in most businesses and responder organisations.

There is a tendency for the government to consider that improvements require new toys at Central Government level and more standards and accountability at the local levels. This is seen to be true in this report to a certain extent with a new Resilience Directorate, a newish National Situation Centre (SitCen), a new Government Head of Resilience role, a CNI knowledge base, a measurement of socio-economic resilience and vulnerability and the Resilience Academy for central Government on the one hand and a set of standards for energy, water, digital, road and rail services, to be reviewed and updated every five years on the other.

But there is new funding for the LRFs for at least three years and moves to build accountability into the Central Government roles with the proposed Annual Statement to Parliament on civil contingencies risk and performance.

[1] https://quoteinvestigator.com/2021/05/04/no-plan/