Defence Research and Development Canada Recherche et développement pour la défense Canada Canada...

Defence Research andDevelopment Canada

Recherche et développementpour la défense Canada Canada

CRTI 07-0103RD: Full Scale RDD Experiments and Models

Dr. Lorne ErhardtGroup Leader, Radiological Analysis and Defence

Defence R&D Canada – Ottawa

Public Security S&T Summer Symposium16 June 2009

Defence R&D Canada • R & D pour la défense Canada

Presentation Outline

• Radiological Terrorism

• RDD Hazard Overview

– What are the major hazards?

• RDD Experimental Work

– What do we need to study, why and what we’re doing.

– Full-Scale RDD Experiments and Models

• Conclusion



Introduction: Radiological Terrorism


What is Radiological Terrorism?

• Radiological terrorism is the use of radioactive material to cause harm

• “Harm” could be a lot of things:– Death

– Acute effects: Radiation sickness

– Chronic effects: Increased cancer risk

– Economic effects: Contamination

– Psychological effects

• The amount and type of harm that a radiological weapon can inflict depends greatly on the design of the weapon


Types of Radiological Weapons

• For a radioactive source to be dangerous, it must be put into a configuration that allows people to be exposed to it (accidentally or maliciously)

• There are two main types of radiological weapons:

– Radiological Exposure Devices• Source deployed in order to irradiate people; Simplest

form of radiological attack

– Radiological Dispersal Devices• Radioactive sources dispersed by explosive or non-

explosive means



RDD Experimental Work:

Objectives and Relevance


Why are we studying RDD effects?

• Effectiveness of radiological dispersal devices subject to debate

– "Dirty Bombs" Much More Likely to Create Fear than Cause Cancer

• American Institute of Physics, www.aip.org

– Radiological attacks constitute a credible threat

• Federation of American Scientists, www.fas.org

• Strategies to protect first responders, the public and critical infrastructure against RDDs must be made in the planning stage, not in the early period just after an attack.

• The development of guidelines for first responders dealing with radiological terrorism incidents requires experimentally verified data on the effects of RDDs.


What do we need to determine?

• For atmospheric dispersion (and other hazard assessment) codes we need the “Source Term”– Particle size distribution and spatial distribution

• We must understand:– Mechanism for material break-up

• Melting, vaporization, solid fracture

– Energetic mechanisms for spatial distribution• Buoyant rise, fragment throw

– Modifications to source term• Agglomeration, shock sintering, secondary aerosolization

• Many time and distance scales involved• This all depends greatly on the design of the device


• Pre-detonation– External hazard, maybe some contamination

• Detonation gives:– Small particles “respirable” < 10 µm

• Inhalation hazard, cloudshine

– Medium/large particles 10 – 500 µm• Contamination/groundshine downwind

– Fragments > 500 µm• Shrapnel/groundshine near blast

• Longer term hazards– Resuspension, ingestion, skin/wound contamination

• Need to understand all aspects to quantify hazard

Understanding RDD Hazards


Solid fracture(along grain boundaries)

Solid fracture(energy limited spall )

> 100 m

Solid fracture(across grainBoundaries)

Comminutionpeak

Phase change(liquid)

Phase change(vapor)

Solid fracture(along grain boundaries)

Str

ess

Particle Size

Solid fracture(energy limited spall )

Solid fracture(across grainBoundaries)

Comminutionpeak

Phase change(liquid)

Phase change(vapor)

Slide courtesy Sandia LabsFinal size distribution can be a combination of several of thesePeaks and can be modified by combustion and agglomeration

Different stress induced mechanisms resultin different initial particle size peaks


Desired Source-Term Modelling Capability

• Desired Capability:

– Given a suspect package, take a radiograph

• Also, dose rate measurement and isotope ID

– Quickly (5 min) model the device to determine potential inhalation and ground-shine hazards

– Make a determination on disruption and mitigation techniques (and associated consequences)

• Modelling an RDD is difficult, examples:

– Disc of ceramic with disc of explosives

• Uncertainty in downwind hazard

– Local contamination hazard from ballistic fraction


High Speed Video: February 2007, Valcartier


Regular Speed Video: February 2007, Valcartier


High Speed Video: February 2007, Valcartier


Regular Speed Video: February 2007, Valcartier


Video: Sandia Laboratories



RDD Experimental Work:

Progress, Results and Impact


Full-Scale RDD Experiments and Models

• New CRTI Project is a follow-on from CRTI 03-0018RD “Experimental Characterization of Risk for RDDs”

• Most ambitious RDD modelling and experimental program to date– Will provide a unique dataset

• Indoor and outdoor explosive tests with coordinated source-term modelling program

• Federal Government Partners:– DRDC Ottawa – RAD/FFSE– DRDC Suffield – CTTC– DRDC Valcartier – EM– Health Canada– Natural Resources Canada– Environment Canada

• Academic Partners:– Royal Military College– Acadia University

• Industry Partner:– International Safety Research

• International Participants:– UK Atomic Weapons Establishment– US Sandia National Laboratories– New England Complex Systems Institute


• Indoor Explosive Dispersal Experiments (Valcartier)

– Explosive dispersal indoors, non radioactive

– Aerosol collection to determine airborne hazard

• RDD Modelling Program (Ottawa)

– Comprehensive look at existing relevant models

• Different models for various time and distance scales

• Create tool kit and best practices for combining models

– Agent-based modelling approach to cross scales

• Outdoor Explosive Dispersal Experiments (Suffield)

– Two series of tests in 2011, each three weeks

Full-Scale RDD Experiments and Models


Recent Progress

• CAN/UK/US RDD modelling workshop held in November 2008 in Albuquerque NM– Input from a variety of subject matter experts

– Defined best approaches for both the modelling and experimental programs

• Modelling effort has focused on evaluation of existing relevant codes, moving on to best practices for integration– Modelling of experimental configuration is just beginning

(Canada and UK)

• Experimental parameters defined after last workshop– Safety of experiments is first priority, but must maintain

relevance to the RDD problem

– Indoor source term experiments to focus on modelling gaps and to test the defined outdoor experiments


Conclusions

• Radiological terrorism involves getting a radioactive substance into a configuration where it can cause harm

• RDDs produce different particle sizes leading to different hazards

• To fully characterize the hazard you need to determine the “Source Term”– This is difficult due to the great dependence on:

• Device design • Material properties

• CRTI 07-0103RD: Full Scale RDD Experiments and Models is addressing these issues– Extensive experimental program is designed to fill gaps in and

validate the modelling effort– International collaboration including UK and US participants– Will result in an ability to quickly evaluate emerging threats

• Already has resulted in increased understanding of relevant issues

Defence Research and Development Canada Recherche et développement pour la défense Canada Canada...

Documents

Transcript of Defence Research and Development Canada Recherche et développement pour la défense Canada Canada...