Registration Dossier

Administrative data

Endpoint:
additional toxicological information
Type of information:
other: Modelling assessment to set acute exposure limits for 2-BTP
Adequacy of study:
key study
Study period:
July 30 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: PBPK modelling performed according to EPA approved model

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Type of study / information:
Modelling assessment using an approved EPA model performed based on previous study results
Test guideline
Qualifier:
no guideline required
Principles of method if other than guideline:
The method used to develop this data is based on EPA accepted models and FAA advisory materials and reports
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
Not relevant

Results and discussion

Any other information on results incl. tables

The 5 -minute allowable concentration was determined to be 0.95%, just slightly lower than the 1.0% LOAEL for the agent.

Applicant's summary and conclusion

Conclusions:
The report shows the results from PBPK modeling for the Halotron BrX clean agent under exposures of both constant concentration and variable concentration, using the perfect stirrer assumption with and without the benefit of ventilation.The method used to develop this data is based on EPA accepted models and FAA advisory materials and reports. The 5-minute allowable concentration was determined to be 0.95%, just slightly lower than the 1.0% LOAEL for the agent. When applying this data to handheld fire extinguisher applications, oerfect stirrer assumptions may result in overestimations of nose level concentrations for individuals seated or standing within the protected volume, whether it is within an office building or aircraft cabin.The FAA has released additional guidance for developing stratification and localization multiplication factors which take into account the higher relative density of halon replacements as compared to the cabin airdensity, resulting in lower airborne concentrations at or above seated nose level than predicted by the perfect stirrer assumption. The methodology provided in DOT/FAA/TC-14/50, Stratification and Localisation of Halon 1211 Discharged in Occupied Aircraft Compartments, may be used to create statification and localisation multiplication factors for specific aircraft and applied to the data within this report to provide more accurate exposure scenarios.