CBRN Respirators5

1
NIOSH-SBCCOM

• SCBA CBRN Standard Presentation

2
Three Tier Approval

• NIOSH 42 CFR, Part 84, Subpart H
• NFPA 1981 Standard for Open Circuit Self
  Contained Breathing Apparatus for Fire Fighters,
  Current Edition
• Special Tests
• Chemical Agent Permeation and Penetration
  Resistance Against Sarin (GB) and Distilled
  Sulfur Mustard (HD)
• Laboratory Respirator Protection Level

3
Why NFPA 1981

• Identified Requirements for SCBAs
• Breathing flow rates
• Breathing resistance
• Communication
• Switch over
• Vision
• Requirements met by NFPA-1981

4
NFPA 1981 Technical Requirements

• Additional flow (100 L/pm vs. 40 L/pm)
• Higher tolerance on breathing resistance
  Exhaled
• Flame and heat resistance
• Rough handling (vibration)
• Corrosion resistance
• Temperature extremes and cycling
• Communications
• Abrasion resistance

5
NFPA Procedural

• Consensus standard
• Voluntary
• Certification organization requirements
• Safety Equipment Institute
• ISO provisions

6
Chemical Agent Permeation and Penetration
Resistance Testing

• Agent Selection Basis
• USA CHMMP Tech Guide 244
• NFPA 1994
• Sensitive Data Sources
• Selection based on Physical Properties/ Molecular
  Structure
• Sarin (GB) and Sulfur Mustard (HD) selected as
  test representative agents
• GB is a vapor test
• HD is a combination liquid-vapor test

7
Chemical Agent Permeation and Penetration
Resistance Testing

• Sarin (GB)
• Most Volatile of nerve agents
• Low molecular weight and molecular configuration
  make it permeate through materials
• Sulfur Mustard (HD)
• Good permeation characteristics
• Long use as army agent of choice for testing
• Linear molecular structure
• Vapor challenge will test for leaks while liquid
  is testing permeation

8
Chemical Agent Permeation and Penetration
Resistance Testing

• Selection of Test Concentrations
• Review of risks and hazards
• Characteristics of materials
• Data review and consultation
• Consideration of scenarios
• Evaluation of
• Physical characteristics
• Estimate of threat characteristics
• Vapor based estimates
• Modeling (use of In De Vap)

9
Chemical Agent Permeation and Penetration
Resistance Testing

• Selection of Test Concentrations
• Twenty-eight plausible incident scenarios modeled
• Hazardous concentrations from 2 mg/m3 to 11,700
  mg/m3 for GB
• Hazardous concentrations from 0.02 mg/m3 to 610
  mg/m3 for HD
• Consideration of SCBA use scenario

10
Chemical Agent Permeation and Penetration
Resistance Testing

• Basis Existing threat characteristics, vapor
  pressure based estimates and modeling scenarios
  and their concentration profiles
• Challenge Concentrations

Agent Vapor concentration (mg/m3) Vapor Challenge Time (Min) CT (mg-mm/m3) Min Sampling Test Period (360)
GB 2000 30 60,000 360
HD 300 30 9,000 360
11
Chemical Agent Permeation and Penetration
Resistance Testing

• Determination of Breakthrough
• Breakthrough predetermined concentration
  detected inside the face piece or simulated air
  stream
• Military acceptable risk does not translate
  well to civilian emergency responders
• Prior determination of HHS set end point values
  at worker population limits (WPL)

12
Chemical Agent Permeation and Penetration
Resistance Testing

• WPL limits or concentrations of chemical agent
  that an unprotected worker can be exposed to
  during an 8-hour, time weighted average (TWA)
  work-shift
• Breakthrough Concentrations
• (mg/m3)

Agent WPL Breakthrough Concentration
GB 0.0001 0.0001
HD 0.0004 0.0004
13
Chemical Agent Permeation and Penetration
Resistance Testing

• Standard Testing Procedure
• SBCCOM will conduct NIOSH Tests at Chemical Test
  Facility, APG (Edgewood) MD, Dugway Proving
  Ground, UT
• STP leverages military mask testing techniques
  developed for evaluation of fielded mask systems
• Procedure is used to test SCBAs against both GB
  and HD
• Detectors used for both agents have same
  sensitivity
• Both agents penetrate leak paths at similar rates

14
Chemical Agent Permeation and Penetration
Resistance Testing

• Key Equipment
• Similar to agent resistant test Minicam
  (SMARTMAN)
• MINICAMS (Miniature Continuous Atmosphere
  Monitoring System) (Gas chromatograph
  calculates agent over time)
• Syringe Pump (controls rate of agent)
• Miller-Nelson control system (environmental
  control)
• Exposure chamber
• Mixing chamber (mixes agent vapor and air)
• Breather pump

15
Chemical Agent Permeation and Penetration
Resistance Testing

• Concerns with other CWA/ TIC
• VX low volatility, lower permeation rate
• L Hydrolyzes rapidly, limited permeation,
  unavailable
• CG and AG Very high volatility, non-persistent
  vapor concentration, lower toxicity
• Chlorine low toxicity, lack of persistence
• Dimethyl Sulfate low toxicity
• Ammonia low toxicity, low persistence

16
Chemical Agent Permeation and Penetration
Resistance Testing

• CWA Toxicities

Agent L CT50 (mg/m3) I CT50 (mg/m3) E CT50 (mg/m3)
GB (skin) 12,000 6,000 1,200
GB (inhalation) 70 35 2
HD (skin) 10,000 2,000 100
HD (inhalation) 1,500 2,000 100
L CT50 medium lethal dosage to 50 of exposed,
unprotected population I CT50 medium lethal
dosage to 50 of exposed, unprotected
population E CT50 medium lethal dosage to 50
of exposed, unprotected population
17
Chemical Agent Permeation and Penetration
Resistance Testing

• Health Effects/ Breakthrough Concentrations
  (mg/m3)

Agent IDLH Minimum Effects Level Severe Effects Level WPL STEL GPL AEGL-1 8 hour Exposure
GB 0.1 0.008 0.1 0.0001 0.0004 0.000003 0.0010
HD 2.0 0.42 1.7 0.0004 0.003 0.0001 0.0083
18
SCBA Live Agent Testing (LAT)

• GB/ Sarin/ Nerve agent
• 2000 mg/m3 vapor only
• GB Vapor exposure for 30 minutes
• Observe decay for 5.5 hours
• HD/ Mustard/ Blister agent
• 300 mg/m3 vapor
• 10 mg/m3 liquid droplets
• Vapor exposure for 30 minutes
• Observe decay for 5.5 hours

19
SCBA Live Agent Testing (LAT)
20
Laboratory Respirator Protection Level

• Test Rationale
• Assure user face seals for aggressive exposures
• Assure minimum levels of protection
• Assess improvements from design modifications
• Assess higher protection levels of modern face
  piece technology
• Create protection level data on standardized
  method
• Use method with highest correlation to biomarker
  method

21
MSA GB
22
MSA HD
23
Scott GB
24
Scott HD
25
Interspiro GB
26
Interspiro HD
27
Interspiro HD Test 1
28
Laboratory Respirator Protection Level (LRPL)

• Test Facilities
• U.S. Army SBCCOM
• Mask Fit Test Facility Edgewood, Md.
• Characterized chamber and detection system
• Correlate to military test data for Domestic
  preparedness
• Military and civilian test subject cohort
• SBCCOM functions as NIOSH Test Agent

29
LRPL Test Protocol

• High Flow/ Deep probe
• HF DP Full face negative pressure
• Corn oil aerosol 0.4-0.6 µm MMAD
• Chamber concentration 20-40 mg/m3
• LANL anthropometric panel
• 11 Exercises (8 OSHA 3 emergency responder)
• Protection level range (1-100,000, 500 min.)

30
LRPL Test Data Collection

• 16 Subjects in requisite LANL cells
• 6 replicates for 96 data points
• Expert assisted donning
• Results part of NIOSH approval certificate

31
CBRN SCBA SUMMARY

• FIRST CBRN SCBA Certified 5/02.
• 
  Edgewood lead
• 
  Dugway Survey
• 
  SCBAs Enroute
• 
  SCBAs Onsite
• CCTF strengths
• CCTF concerns
• CCTF needs
• 1Aug02 Y/N?