Final—October 9, 2014

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## Significant New Alternatives Policy Program Fire Extinguishing and Explosion Prevention Sector

Risk Screen on Substitutes for Total Flood ing Systems in Norma lly Occupied Spaces

Substitute: Powdered Aerosol D (Stat-X ® 

### )

This risk screen does not contain Clean Air Act (CAA) Confidential Business Information (CBI) and, therefore, may be disclosed to the public.



### 1. INTRODUCTION

Ozone-depleting substances (ODS) are being phased out of production in response to a series of diplomatic and legislative efforts that have taken place over the past two decades, including the Montreal
Protocol and the Clean Air Act Amendments of 1990 (CAAA). The U.S. Environmental Protection Agency (EPA), as authorized by Section 612 of th e CAAA, administers the Significant New Alternatives Policy (SNAP) Program, which identifies acceptable and unacceptable substitutes for ODS in specific end-uses based on assessment of their health and environmental impacts.

EPA’s decision on the acceptability of a substitute is based on the findings of a screening assessment of potential human health and environmental risks posed by the substitute in specific applications. EPA has already screened a large number of substitutes in many end-use applications within all of the major ODSusing sectors including: refrigeration and air conditioning, solvent cleaning, foam blowing, aerosols, fire suppression, adhesives, coatings and inks, and sterili zation. The results of these risk screens are presented in a series of Background Documents that are available in EPA's docket.

The purpose of this report is to supplement EPA’s Background Document on the fire extinguishing and explosion protection sector (hereinafter referred to as the Background Document, EPA 1994a). This risk screen discusses the potential human health and envir onmental risks posed by Powdered Aerosol D or

Stat-X ® Aero-K ® Fire Suppressant (hereinafter referred to as Stat-X ® ) when used as a flooding agent in normally occupied spaces. There are several applicati ons for this technology including the protection of selected spaces in aircraft, ships and vehicles (includi ng commercial, civilian, and military types), such as vessel engine rooms and machinery spaces (Fireaway, Inc. 2013a). The Stat-X ® system presently has EPA SNAP approval for use as a total flooding fire extinguishing system alternative in normally unoccupied areas. Table 1 details the composition of the proposed substitute prior to activation.

Table 1: Composition of Stat-X® Fire Suppressi on Aerosol Generator Prior to Activation

Component Chemical Formula CAS Number Concentration (Weight Percent)Final—October 9, 2014

2 Table 2 presents the post-activation products and concentrations for Stat-X ® [ ] (Fireaway Inc. 2013a).

Table 2: Post-Activation Products from a Discharge of Stat-X ® Fire Suppression Aerosol Generator

Component Chemical Formula CAS Number Concentration (Weight Percent)*

Section 2 of this report summarizes the results of th e risk screen for the proposed substitute for use in normally occupied spaces. The remainder of the report is organized into the following sections:

 Section 3: Atmospheric Assessment

 Section 4: Potential Health Effects

 Section 5: Occupational Exposure Assessment

 Section 6: End-Use Exposure Assessment

 Section 7: General Population Assessment

 Section 8: Volatile Organic Compound Assessment

 Section 9: References



### 2. SUMMARY OF RESULTS

Powdered Aerosol D (Stat-X ® ) is recommended for SNAP approval as a total flooding agent in normally occupied spaces. EPA’s risk screen indicates that the u se of the proposed substitute is not expected to pose a significant toxicity risk to personnel or the general population. It is expected that procedures identified in the material data safety sheet (MSDS) for Stat-X ® and good manufacturing practices will be adhered to, and that the appropria te safety and personal protective equipment (PPE) (e.g., protective gloves, tightly sealed goggles, protective work clothi ng, and particulate-removing respirators with NIOSH type N95 or better filters) 1 consistent with OSHA guidelines will be used, as applicable, during manufacture and disposal of total flooding systems using Stat-X ® . Because units are to be installed in normally occupied spaces that are equipped with featur es such as a system-isolate switch and cross-zone detection system, risk of accidental activation of a Stat-X ® generator while persons are present in the protected space is not likely. Additionally, warning of pending discharge and delay in release to ensure egress prior to activation of the agent is required to reduce the risk of exposure. EPA’s risk screen also indicates that the use of the proposed substitute will be less harmful to the atmosphere than the continued

use of Halon 1301 and substitutes used in this sect or, such as HCFC Blend A, HFC-227ea, and HFC-125,as it is less harmful to the ozone layer, has lower climate impact, and a shorter atmospheric lifetime. StatX ® ’s contributions to volatile organic compound (VOC ) emissions is not significant, as all of its components following activation are exempt under CAA regulations (40 CFR §51.100(s)).

1 As described by the CDC (1997), a particul ate removing respirator filters out dust, fibers, fumes and mi sts by filtering, absorbing, adsorbing, or causing a chemic al reaction with the contamin ants as they pass through the respirator canister or cartridge. A list of available NIOSH-approved N95 dis posable particulate respirators can be found here: http://www.cdc.gov/niosh/npptl/topics/r espirators/disp_part/n95list1.htmlFinal—October 9, 2014

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### 3. ATMOSPHERIC ASSESSMENT

This section presents an assessment of the potential ri sks to atmospheric integrity posed by the use of

Stat-X ® as a total flooding fire extinguisher in normally occupied areas. According to the submitter, StatX ® does not contain any halogens so its oz one-depleting potential (ODP) is zero. [ ]

The proposed substitute is substantially less harmful to the ozone layer, has lower climate impact, and a shorter atmospheric lifetime compared to Halon 13 01. In addition, the pre- and post-activation
constituents of Stat-X ® have lower climate impacts and shorter atmospheric lifetimes than those predicted for other substitutes examined in the Background Do cument, as well as a commonly utilized substitutes. Thus, EPA believes that use of Stat-X ® would result in substantially less harm to ozone layer than the continued use of ODS and commonly used ODS substitutes, and will also have a lesser impact on the climate system.

Table 3: Atmospheric Impacts of Stat-X ® Compared to Other Flooding Agents

Chemical ODP GWP ALT (years) Proposed Substitute

Other Flooding Agents

Halon 1301 15.9 d 7,140 e 65 e HCFC Blend A f 0.035 d 1,546 e NA g HFC-227ea 0 3,220 e 34.2 e HFC-125 0 3,500 e 29 e

a [ ]

b [ ]

c [ ]

d WMO (2010)

e IPCC 4 th Assessment Report (Forster et al. 2007)

f HCFC Blend A is a blend consisting of HCFC-123 (4.75%), HCFC-22 (82%), HCFC-124 (9.5%), and D-limonene (3.75%).

g Atmospheric lifetimes are not given for blends because the components separate in the atmosphere. The ALT for HCFC-123 is 1.3 y ears, HCFC-22 is 12 years, HCFC-124 is 5.8 years, and D-limonene ranges from less than a minute to a few hours (IPCC 4 th Assessment Report [Forster et al. 2007] and WHO 1998).



### 4. DISCUSSION OF END-USE SCENARIOS

Stat-X ® is proposed for use as a total flooding fire extingui shing agent in normally occupied spaces. There are several applications for this technology includin g the protection of selected spaces in aircraft, ships and vehicles (any of which might include military ve rsions), such as vessel engine rooms and machinery spaces (Fireaway, Inc. 2013a). Prior to activation, the Stat-X ® formulation (see Table 1) is contained as a solid disk of chemicals in a double-walled, insulated, and hermetically-sealed steel container. [ ] In response to heat and lack of oxygen, the formulation undergoes a chemical reaction; once the Stat-X ® system is activated, it generates and discharges a hom ogenous mixture of gas and particulates into a space containing a fire hazard or directly on the hazard itself, extinguishing the fire.

In normally occupied spaces, the Stat-X ® aerosol generators are either manually or electrically activated. The electrical units are activated by an electrical signal from a UL-approved releasing panel and also possess a manual release system. 2 The manual activation option serves as a back-up method in the event
there is a failure in the electrical activation contro ls and as the primary option in spaces where automatic activation is specifically prohibited, such as in ma chinery spaces and cargo pump rooms aboard merchant

2 Note that safeguards against false activation are part of the testing and requirements for the UL-approved detection and releasing panels utilized in the system.Final—October 9, 2014

4 ships according to the International Maritime Or ganization (IMO) (Fireaway Inc. 2013a). Manual activation systems ensure that all personnel ha ve exited the space prior to activation. Stat-X ® generators range in charge size from 30 grams to 2,500 grams and are installed singly or in multiples as required by the volume and configuration of the protected space in addition to the hazard rating. In accordance with the UL listing, the final design concentration of Stat-X ® is 97 g/m 3 for Class A fires and 67 g/m 3 for Class

B fires. 3 Actual concentrations will not normally exceed 100 g/m 3 . [ ]

[ ] This risk screen discusses the potential risk of occupational exposu re during installation and servicing and end-use exposure based on this worst-cas e scenario maximum concentration.



### 5. POTENTIAL HEALTH EFFECTS

Because the fire suppressant precursors are prepared in tablets that are non-reactive and do not crumble or flake, there is no concern with regard to inhalatio n or ingestion of the pre-activation compounds. The post-activation products that might be released in the event of an accidental discharge are listed in Table 2, above. The hazardous gaseous components of Stat-X ® [ ] are not present in great enough concentrations to pose a significant toxicity risk. If the genera tor is activated, possible exposure to the aerosol suppression agent may cause temporary, mild irritation of the mucous membrane. If eye or skin contact occurs, end users should flush eyes with water or wa sh skin with soap and water. According to the submitter, laboratory studies have concluded that exposure to Stat-X ® fire suppressant for approximately 15 minutes has no significant observable respiratory, dermal or ocular effects.

The discharge of the aerosol, however, does result in a reduction of visibility in the protected space due to the uniform distribution of the particulate generated (Fireaway, Inc. 2013a). NFPA 2010 4 requires that a warning of pending discharge and delay in release is required to minimize the possibility of a system discharge when personnel are still present in the protec ted space. This standard also requires a supervised disconnect switch to avoid unwanted discharge of an aerosol system during maintenance, which the submitter indicates is installed on the releasing circ uit and at the entrance to the protected space (Fireaway, Inc. 2013b). In addition, EPA recommends that cross-zone detection systems and abort

switches located near an exit from th e protected space are employed.



### 6. OCCUPATIONAL EXPOSURE ASSESSMENT

The potential for personnel exposure during manufacture, installation and servicing are examined in this section. To evaluate occupational exposure, EPA h as evaluated the risks associated with discharge scenarios which are assumed to occur accidentally and not as the result of a fire. Therefore, the

recommendations made in this section shall onl y apply to accidental releases of the Stat-X ® compound.

6.1. Occupational Exposure during Manufacture

As described by the submitter, there is limited e xposure to the product during manufacturing. The
chemicals in the Stat-X ® formulation are pressed into a solid disk and then shipped to the Stat-X ® manufacturing facilities under U.S. Depart ment of Transportation regulations. 5 The agent, in its pressed form, is flammable with an auto-ignition temperatur e of 300°C. However, upon receipt, it is contained within a double-walled, insulated, and hermetically sealed steel container. [ ] Therefore, exposure to

3 Class A fires involve ordinary combustibles, such as paper, trash, some plastics, wood and cloth. A rule of thumb is if it lea ves an ash behind, it is a Class A fire. Class B fires involve fla mmable gases or liquids, such as propane, oil and gasoline (OSHA 2009).

4 NFPA 2010: Standard for Fixed Aeroso l Fire-Extinguishing Systems (NFPA 2010)

5 Potassium Nitrate is a Hazard Class 5.1, UN Number UN1486, Packing Group III.Final—October 9, 2014

5 flame and risk of ignition is unlikely. Because the constituents of Stat-X ® arrive at the manufacturing facility pressed into solid disks, exposure is only li kely when chemicals are processed into disks. Employees responsible for chemical processing shoul d wear the appropriate PPE, such as protective gloves, tightly sealed goggles, protective work clothi ng, and particulate-removing respirators with NIOSH type N95 or better filters consistent with OSHA guidelines. Production facilities are ISO 9001:2008 certified and qualified to MIL procedures (Gross 2006; Fireaway, Inc. 2003). Additionally, the manufacturing space should be well ventilated with a lo cal exhaust system, and an eye wash fountain and quick drench facilities must be close to the producti on area. In the worst cas e scenario of accidental
activation of the Stat-X ® generator, workers should immediately vacate the premises and follow the first aid guidelines listed in the MSDS. EPA believes if these exposure controls are employed and the appropriate occupational safety guidelines are adhe red to, significant occupational exposure during

manufacture of Stat-X ® is not expected to occur.

6.2. Occupational Exposure during Installation and Servicing

Exposure to Stat-X ® is not likely during installation or servicing of Stat-X ® generators as the formulation

is in solid form and is contained within a double-walle d, hermetically sealed metal cylinder. As indicated by the submitter, the risk of accidental activation of a Stat-X ® generator while personnel are present in the protected space is highly unlikely if proper procedur es are followed. The electrical units, which would be installed in normally occupied spaces, are equipped with a system-isolate switch (located outside the protected area) that, when activated with a key, inhib its automatic activation of the system while the fire detection and alarm systems continue to function. Ho wever, in the situation where the system could be activated while persons are present in the protected space, the activation system normally incorporates a cross-zone detection system and time delay. Upon de tection in one zone, a warning strobe sounds and a 30-second time delay occurs prior to system release when the detection system is activated in a second zone. This time delay and two-z one alarm system allows any personnel present in the protected space without the system-isolate switch turned on to exit prior to system discharge. Proper instructions on system isolation included in both the design and owner’s manuals for the Stat-X ® systems should be

adhered to.

In the event of discharge, accidental or otherwise, protective gloves, tightly sealed goggles, protective work clothing, and particulate-removing respirators with NIOSH type N95 or better filters should be worn if entering the normally occupied space after the ev ent (Fireaway, Inc. 2013a). As indicated by the submitter, 97 percent of the par ticulate matter is less than 5 μ m, and 76 percent is less than 3 μ m, making the particulate matter highly respirable and able to reach the extrathoracic, tracheo-bronchial, and pulmonary regions of the respiratory system (Fir eaway, Inc. 2003; EPA 1994b). Based on the design concentration and percent of particulate matter dischar ged, the levels of respir able dust could reach 67.9 g/m 3 , far exceeding ACGIH’s limit of 10 mg/m 3 for total inhalable dust and 3 mg/m 3 for the respirable fraction (ACGIH 2006). Personnel shou ld not enter the space following the discharge until all particles have settled and/or ventilated. Based on the partic le size distribution information provided by the submitter and predicted settling rates of aerosol particul ates in still air from the Institute of Medicine, the majority of the particles (76 percent), which are betw een 1 and 3 μm, would take 4 to 8 hours to settle just one meter (Institute of Medicine 2000). Therefore, it is likely that the majority of the particles released will be released from the space during ventilation.



### 7. END-USE EXPOSURE ASSESSMENT

Stat-X ® is not expected to pose significant risk to e nd-users when used as a total flooding agent in normally occupied spaces. According to the Stat-X ® Design, Installation, and Maintenance Manual and in accordance with NFPA 2010, all Stat-X ® systems installed in occupiable spaces must incorporate a pre-Final—October 9, 2014

6 discharge alarm and minimum 30-second time delay to allow for personnel egress prior to system discharge. Depending on the Stat-X ® generator model, the discharge rate is typically in the range of [ ], with the system discharging entirely within a range of 7-37 seconds. Stat-X ® generators range in charge size from 30 grams to 2,500 grams and are installed si ngly or in multiples as required by the volume and configuration of the protected space in addition to the hazard rating.

[ ] According to the submitter, laboratory st udies have concluded that exposures to Stat-X ® fire suppressant for approximately 15 minutes are well within the limits set by NIOSH, which is demonstrated in Table 4. [ ]

[ ] In the event of exposure to Stat-X ® , individuals are expected to follo w the instructions prescribed in the proposed substitute’s MSDS. However, when i ndividuals follow the proper precautionary measures described in Section 4 and Section 5.2, risk of exposure and irritation will be unlikely.

Table 4: End-Use Exposure Assessment of Gaseous Post-Activation Stat-X ® Products

Product Constituent 15-min TWA Exposure (ppm) Design Concentration: 100 g/m 3 Short Term (15-min) Exposure Limits (ppm) IDLH Level (ppm)



### 8. GENERAL POPULATION EXPOSURE

This section screens potential risks to the genera l population from exposure to releases of Stat-X ® to ambient air, surface water, and solid waste. Stat-X ® is not expected to cause a significant risk to human health in the general population when used as a fl ooding agent in normally occupied spaces. The only consumer exposure to Stat-X ® will be during discharge of the generators. When the precautionary measures described in the proposed substitute’s MSDS and Section 4 and Section 5.2 of this risk screen, no adverse health effects are expected.

8.1. Ambient Air

Stat-X ® is not expected to pose a risk to human health in the general population in ambient air concentrations. All manufacturing occurs in a facility w ith a closed ventilation system and in the center of a square mile rural site (Fireaway, Inc. 2013a). Therefore, release of Stat-X ® to ambient air is likely to be minimal, and is not expected to be a safety concern.

8.2. Surface Water

None of the pre- or post-activation constituents of Stat-X ® are listed as priority pollutants or toxic pollutants under the Clean Water Act, except for [ ] (toxic pollutant) which is produced in insignificant quantities (0.009%). However, three of the post-ac tivation constituents [ ] are listed as hazardous substances under the Clean Water Act with reporting qu antities of [ ] respectively. However, given that the maximum capacity of the Stat-X ® generator is 2,500 grams, none of these constituents will exist in in quantities approaching their resp ective reporting quantities. Additionally, disposal of Stat-X ® aerosol
generators is subject to local, state, and federal regul ations, which ensure that releases of Stat-X ®

constituents and water contaminated with Stat-X ® constituents are not be dumped into sewers, on the ground, or into any body of water, but rather taken to a wastewater treatment facility or disposed of properly. Therefore, Stat-X ® is not expected to pose a significant risk to human health or the environment when proper disposal procedures are followed.Final—October 9, 2014

7 8.3. Solid Waste

None of the constituents of Stat-X ® [ ] are considered to be hazardous waste under EPA regulations implementing the Resource Conserva tion and Recovery Act. During post-activation clean-up procedures, clean-up residues should be disposed of in accordance with requirements appropriate for those materials, as outlined in the proposed substitute’s MSDS and local , state, and federal regulations. EPA believes that when these disposal requirements are met, Stat-X ® does not pose a significant risk to the general population or environment.



### 9. VOLATILE ORGANIC COMPOUND (VOC) ANALYSIS

The post-activation constituents of Stat-X ® [ ] are exempt from the definition of volatile organic compound (VOC) under CAA regulations (40 CFR § 51.1 00(s)).Therefore, environmental impacts from
the release of Stat-X ® as a VOC are not a significant concern.Final—October 9, 2014

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### 10. REFERENCES

ACGIH. 2004. The Documentation of the Threshol d Limit Values and Biological Exposure Indices.
American Conference of Governmental Industr ial Hygienists. Available at: www.acgih.org.

ACGIH. 2005. Guide to Occupational Exposure Va lues. American Conference of Governmental Industrial Hygienists.

ACGIH. 2006. Threshold Limit Values for Chemical Substances (TLV®-CS). Dennis Casserly, TLV®- CS Committee, University of Houston at Clear Lake . American Conference of Governmental Industrial Hygienists. Available online at: http://www. acgih.org/tlv/03_TLV-CS-Update_AIHce06.pdf.

CDC. 1997. Respiratory Protection Program Manual. Office of Health and Safety, Centers for Disease Control and Prevention. January 1997.

Folland, C.K., T.R. Karl, J.R. Christy, R.A. Clarke, G. V. Gruza, J. Jouzel, M.E. Mann, J. Oerlemans, M.J. Salinger and S.-W. Wang, 2001: Observed Climate Va riability and Change. In: Climate Change 2001: The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change [Houghton, J. T., Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell, and C.A. Johnson (eds.)]. Cambri dge University Press, Cambridge, United Kingdom and New York, NY, USA. Available online at: http://www.grida.no/climate/ipcc_tar/wg1/pdf/wg1_tar-front.pdf

Forster, P., V. Ramaswamy, P. Artaxo, T. Berntsen , R. Betts, D.W. Fahey, J. Haywood, J. Lean, D.C. Lowe, G. Myhre, J. Nganga, R. Prinn, G. Raga, M. Schulz and R. Van Dorland. (2007). Errata. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Pane l on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tigno r and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Available online at: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-errata.pdf.

Fireaway Inc. 2003. Stat-X ® Aero-K Condensed Aerosol System fo r Use in Normally Unoccupied Spaces in Fire Suppression Sector. Significant New Alternatives Policy Program Submission to the U.S. Environmental Protection Agency. April 2003.

Fireaway Inc. 2013a. Stat-X ® Aero-K Condensed Aerosol System for Use in Normally Occupied Spaces in Fire Suppression Sector. Significant New Alternatives Policy Program Submission to the U.S. Environmental Protection Agency. May 2013.

Fireaway Inc. 2013b. Response to Incompleteness Letter for Stat-X ® Aero-K Condensed Aerosol System for Use in Fire Suppression Sector. July 15, 2013.

Gross, Marc. 2006. Personal communication from Ma rc Gross, Fireaway LLC to Bella Maranion, EPA. November 13, 2006.

Institute of Medicine. 2000. Clearing the Air: As thma and Indoor Air Exposures. Committee on the

Assessment of Asthma and Indoor Air. Division of Health Promotion and Disease Prevention. Institute of Medicine National Academy Press. Washington, DC.Final—October 9, 2014

9 National Academy of Sciences (NAS). 2007. Acute E xposure Guideline Levels for Selected Airborne Chemicals: Volume 6. Committee on Acute Exposur e Guideline Levels, Committee on Toxicology,
National Research Council. Available onlin e at: http://www.nap.edu/catalog/12018.html.

NFPA. 2010. NFPA 2010. Standard for Fixed Aeroso l Fire Extinguishing Systems. National Fire

Protection Association.

OSHA. 2009. Fire Protection and Prevention. Occupati onal Safety & Health Administration. Available online at: https://www.osha.gov/dte/grant_mate rials/fy09/sh-18796-09/fireprotection.pdf.

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U.S. EPA. 2012. Acute Exposure Guidelines (AEGLs) Definitions. Available online at: http://www.epa.gov/oppt/aegl/pubs/define.htm.

WHO (World Health Organization). 1998. Concise International Chemical Assessment Document 5 – Limonene. Available online at: http://whqlibdoc .who.int/publications/1998/9241530057.pdf.

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