*****Final

-- May 1 , 201 3***** 

### 1 

## Significant New Alternatives Policy Program Fire Extinguishing and Explosion Prevention Sector
Risk Screen on Substitutes for Halon 1301 Total Flooding Systems in Occupied and Unoccupied Spaces
Substitute: K

- Ace

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 (CAA A). The U.S. Environmental Protection Agency (EPA), as authorized by Section 612 of the CAAA, administers the Significant New Alternatives Policy (SNAP) Program, which identifies acceptable and unacceptable substitutes for ODS in specific end

- uses based o n 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 applicatio ns. EPA has already screened a large number of substitutes in many end

- use applications within all of the major ODS

using sectors, including refrigeration and air conditioning, solvent cleaning, foam blowing, aerosols, fire suppression, adhesives, coating s and inks, and sterilization. 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 risk screen is to supplement EPA’s Background Document on the fire suppression and e xplosion protection sector (EPA 1994) (hereinafter referred to as the Background Document). This risk screen discusses the potential human health and environmental risks posed by K

- Ace when used as a flooding agent in normally occupied spaces as a replacement for Halon 1301. The reader is referred to the Background Document for the methodologies and assumptions used to conduct this risk screen.

K

- Ace is being proposed for a range of applications, including commercial applications, but primar ily military vehicle applications. The K

- Ace system typical ly consists of a one

- gallon cylinder of the proposed s ubstitute , controlled by a dispensing nozzle that releases the proposed substitute in 0 .042 to 555 micron

- sized droplets (average 39.3 microns) at a <90 ° cone spray pattern

. In order to suppress fires, t he extinguisher discharges K

- Ace over a period of 3 to 4 minutes , at a rate of 20 to 

### 80 grams/second

. Table 1 presents the composition of the proposed substitute.*****Final

-- May 1 , 201 3***** 

### 2 Table 1 : Composition of K

- Ace

Constituent Chemical Formula CAS No. Percent of Total (by weight) Potassium Acetate C 2 H 3 KO 2 127

- 08

- 2 50% Water H 2 O 7732

- 18

- 5 50 %
UL listing for K

- Ace systems in military applications is not being sought, although the proposed substitute is anticipated to be primarily used for Class A (ordinary combustibles) and Class B (flammable liquids and gases) fires. Other potassium acetate formulations similar to K

- Ace are currently used in other applications, such as commercial kitchen fire protection

. Section 2 of this risk screen summarizes the results of the risk screen for the proposed substitute. The remainder of the risk screen 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 Exposure Assessment;

• Section 8: Volatile Organic Compound Assessment; and

• Section 9 : References.


### 2. SUMMARY OF RESULTS
K

- Ace is recommended for SNAP approval as a flooding agent in normally occupied spaces. Given that proper training will be provided to personnel and that appropriate personal protective equipment ( PPE ) and proper procedures according to the MSDS (including provision of adequate ventilation) will be used during installation, maintenance, and disposal activities , no significant risks to workers or the general population is anticipated. Section VIII of the Occupational Safety & Health Administration (OSHA) Technical Manual (OSHA 1999) should be consulted for information on selecting the appropriate types of PPE

. Additionally, the risk screen indicates that the use of the proposed substitute will be less harm ful to the atmosphere than the continued use of Halon 1301 and substitutes used in this sector, such as HCFC Blend A, HFC

- 227ea , and HFC

- 125

. 

### 3. ATMOSPHERIC ASSESSMENT This section presents an assessment of the potential risks to atmospheric integrity posed by the use of K

Ace as a flooding agent

. K

- Ace contains no Class I or Class II ODS , nor any compounds with a measured global warming potential (GWP). Therefore, the u se of K

- Ace will be less damaging to the atmosphere than continued use of Halon 1301 , which has a GWP of 7,140 ( Forster et al. 2007) and an ozone depletion potential (ODP) of 15.9 (WMO 2011)

. Furthermore, K

- Ace has a significantly lower impact on the climate than other substitutes used in this sector, such as HCFC Blend A, HFC

- 227ea , and HFC

- 125, as shown in Table 2.*****Final

-- May 1 , 201 3***** 

### 3 Table 2 . Atmospheric Impacts of K

- Ace Compared to Other Flooding Agents
Chemical Ozone Depleting Potential (ODP) Global Warming Potential (GWP) Atmospheric Lifetime (ALT) in Years K

-

Ace 0 0 0 Halon 1301 15.9 a 7,140 b 65 b HCFC Blend A c 0.035 ad 1,546 b NA e HFC

- 227ea 0 3,220 b 34.2 b HFC

- 125 0 3,500 b 29 b

a WMO (2010) b IPCC 4 th Assessment Report (Forster et al. 2007)

c HCFC Blend A is a blend consisting of HCFC

- 123 (4.75%), HCFC

- 22 (82%), HCFC

- 124 (9.5%), and D

- limonene (3.75%)

. d WMO (2007)

e NA= not available. Atmospheric lifetimes are not given for blends because the components separate in the atmosphere. The ALT for HCFC

123 is 1.3 years, 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 Assessme nt Report [Forster et al. 2007] and WHO 1998).


### 4. POTENTIAL HEALTH EFF ECTS According to the MSDS, K

- Ace is not a primary ocular, respiratory, or skin irritant, and is not considered to be orally toxic. However, K

- Ace may irritate the eyes and cause prolonged impairment of vision if it is directly in contact with the eyes for an extended duration. If contact with eyes occurs, immediately flush the eyes with water for at least 15 minutes, holding the eyelids open; contact lenses should be removed, if
worn

. Inhalation is not expected to pose a risk. In the case of dermal exposure, the skin should be rinsed with soap and water. Excessive ingestion (>25 grams) of K

- Ace may irritate the digestive tract, resulting in nausea, vomiting, and/or diarrhea ; in sensitiv e populations, muscular weakness, burning, tingling and numb ing sensations of hands and feet, reduced blood pressure, irregular or slower heartbeat, and cardiac arrest may also occur

. Should K

- Ace be ingested , the person should drink water or milk; vomitin g should not be induced unless directed by medical personnel. If medical advice cannot be obtained, the person should be brought to a medical emergency treatment center or hospital. Because the PPE recommendations outlined in the MSDS for K

- Ace and Sectio n 5. 2 of this risk screen are followed, t hese potential health effects are unlikely to occur

. 

### 5. OCCUPATIONAL EXPOSUR E ASSESSMENT The potential for personnel exposure during manufacture, installation, and maintenance are examined in this section. D ischarge scenarios discussed are assumed to occur accidentally and not as the result of a fire. In order to evaluate occupational exposure, EPA has evaluated the active compound contained in K

Ace, potassium acetate

. This compound exhibits low toxicity a nd has been approved by the U.S. Food and Drug Administration (FDA) for injection to treat diabetic ketoacidosis (FDA Application No. NDA 018896). Further information on t he common application types, FDA approval status , and associa ted hazards for this com pound are presented in Table 3

.
Table 3 : Common Applications Types and FDA Approval Status of Potassium Acetate

Constituent Common Application Types FDA Approval Status a,b Associated Hazards

Potassium acetate - Food

- Pharmaceuticals

- Textiles - FDA

- approved as synthetic flavoring (21 CFR 172.515) - Minor eye irritation

- Minor skin irritation

- Minor respiratory tract irritation

- Gastrointestinal discomfort

a FDA = U.S. Food and Drug Administration b FDA approvals are subject to use restrictions. Please see the cited regulation for further information.*****Final

-- May 1 , 201 3***** 

### 4 5.1. Occupational Exposure during Manufacture K

- Ace is not expected to pose a risk to workers during manufacture. As indicated by the submitter, K

- Ace is handled in a closed system from the time it is received by the submitter until it is shipped out in filled cylinders. Specifically, 300 gallons of K

- Ace is received at the facility as a liquid in totes which are then elevated on a rack

. C ylinders are then gravity

- filled from the totes through a solenoid valve controlled by
a flow meter. Once filled, the valve assembly is installed, the cylinder pressurized and assembly leak checked, and then the cylinders packed and stored in a carton on a pallet (Amerex 2012 ) . Since the manufacturing process is a closed system with no direct handling of agent, occupational exposure during manufacture of K

- Ace is not expect ed to occur and EPA believes that manufacture of K

- Ace does not pose a significant risk to human health.
5.2. Occupational Exposure during Installation and Maintenance K

- Ace is not expected to pose a significant risk to personnel during installation and maintenance activities , even in the case of an inadvertent discharge of the entire charge

. In such cases, the proposed substitute will discharge and settle as a water mist, and as a result, significant o xygen displacement is not expected to occur

. In addition, as noted above, potassium acetate, the only active ingredient of K

- Ace,
e xhibit s low toxicity and is commonly used in food , pharmaceutical, and textile applications

. For measures designed to minimize the hazards associated with K

- Ace , the proposed substitute ’s MSDS should be referenced. In order to protect workers from exposure , EPA has outlined the following recommendations in accordance with established good manufacturing practices :

• Training for safe handling procedures should be provided to all employees that would be likely to handle the containers of K

- Ace or extinguishing units filled with the material;

• 

### All employees handling the proposed substitute wear PPE selected in accordance with the OSHA Technical Manual

. • Adequate ventilation should be in place,

• All spills should be cleaned up immediately in accordance with good industrial hygiene practices. By adhering to safety guidelines, the potential for worker exposure s to K

- Ace during installation and maintenance will be unlikely

. It is recommended that the proposed safe handling training also focus on prevention of an inadvertent discharge. In case of an inadvertent discharge, workers should immediately follow the instructions listed in the MSDS for K

- Ace

. 

### 6. END

- USE EXPOSURE ASSESSM ENT
K

- Ace is not expected to pose significant risk to end

- users when used as a flooding agent in normally occupied spaces

. The submitter has indicated that the typical design density for K

- Ace ranges from 24 to 120 grams per cubic foot (850

- 4,240 g/m 3 ). Specifically , K

- Ace is primarily designed for use i n military applications and t he total amount of agent released is expected to vary from 1 to 2 gallons in a vehicle system (with crew compartment volumes ranging from 100

- 250 ft 3 ) and 30 to 70 gallons in a 9,200 ft 3 ( 260 m 3 ) room system

. The discharge rate of K

- A ce is typically in the range of 20 g/sec to 80 g/sec , with the extinguisher discharg ing entirely within 3

- 4 minutes.

Based on the most conservative scenario of these figures , the maximum exposure concentration of K

- Ace that an end

- user would be exposed to is approximately 96 g/ft 3 ( 3 ,40 0 g/m 3 ), assuming that the entire extinguisher is released and suspended in air. However, this is an extremely conservative estimate. T he airf low rate is not considered in this assessment , but the crew compartment of military vehicles are expected to be ventilated at an air flow rate of approximately 25

- 150 ft 3 / min , which would fur ther decrease the concentration of suspended K

- Ace

. Because of the low toxicity exhibited by K

- Ace and the low inhalation concentrations anticipated during discharge, K

- Ace is not considered to present a significant inhalation risk at end

- use.*****Final

-- May 1 , 201 3***** 

### 5 Dermal and ocular exposure to K

- Ace is not expected to pose a significant risk to end

- users. In the event of exposure to K

- Ace , individuals are expected to follow the instructions prescribed in the proposed substitute’s MSDS. When individuals follow the precautionary measures described in Section 

### 4 and Section 5.2 , risk of exposure and irritation will be unlikely

. 

### 7. GENERAL POPULATION EXPOSURE ASSESSMENT This section screens potential risks to the general population from exposure to releases of K

- Ace to ambient air, surface water, and solid waste

. K

- Ace is not expected to cause a significant risk to human health in the general population when used as floo ding agent in normally occupied or unoccupied spaces. The only consumer exposure to K

- Ace will be during discharge of the extinguishers in occupied spaces. 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.
7 .1. Ambient Air K

- Ace is not expected to pose a risk to human health in the general population in ambient air concentrations. K

- Ace is composed of water (50%) and potassium acetate (50%) , which is commonly used in pharmaceuticals, foods, and textiles. Therefore, K

- Ace is not expected to be a safety concern for ambient air contamination.
7 .2. Surface Water K

- Ace is not expected to pose a significant risk to human health or the environment when proper disposal procedures in accordance to local, state, and federal requirements are followed

. K

- Ace is considered to be readily biodegradable and relatively harmless to aquatic life. As discussed in the Background Document, the physicochemical properties of the majority of halon substitutes make it unlikely that the substitutes would be released t o surface water as a result of use. In the case of K

- Ace , it is expected that all of the constituents would rapidly aerosolize during expulsion from the container and then settle as a salt water film on surfaces within the space (as opposed to becoming air borne and settling on a nearby stream)

. After settling, cleanup would involve confining the release , recovering as much of the potassium acetate solution as possible, then washing/rinsing of surfaces , and then disposing of the waste i n accordance with local, state, and federal requirements. It is important to note that a ctivation of K

- Ace systems are expected to be infrequent (i.e., in case of a fire emergency), where the greatest risk is exposure to fire and lack of oxygen. EPA belie ves that when the disposal procedures are followed in accordance to local, state, and federal requirements , K

- Ace does not pose a significant risk to human health or the environment during end

- use.
7 .3. Solid Waste K

- Ace is not considered to be hazardous waste under EPA regulations implementing the Resource Conservation 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 p roposed substitute’s MSDS and local, state, and federal regulations. EPA believes that when the se disposal requirements are met , K

- Ace does not pose a significant risk to the general population or environment

. 

### 8. VOLATILE ORGANIC COM POUND ASSESSMENT Potassium acetate and water, the only constituents of K

- Ace , are not considered to be volatile organic compound s (VOC s )

. Therefore, emissions of K

- Ace are not considered to be a contributor to VOC emissions.*****Final

-- May 1 , 201 3***** 

### 6 9. R EFERENCES Amerex Defense . 2012a. Response to Incomplete SNAP Submission for K

- Ace in Total Flooding End

Use. May 24, 2012. Amerex Defense. 2012a. Response to Incomplete SNAP Submission for K

- Ace in Total Flooding End

Use. July 13, 2012.
Amerex Defense. 2011c. SNAP Submission to E PA for K

- Ace in Total Flooding End

- Use. February 8, 2012.
EPA 1994. "Risk Screen on the Use of Substitutes for Class I Ozone

- depleting Substances: Fire Extinguishing and Protection (Halon Substitutes)," U.S. Environmental Protection Agency, March 1994. 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. Changes in Atmospheric Constituents and in Radiative Forcing. In: Climate Change 2007:The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. C ambridge University Press, Cambridge, United Kingdom and New York, NY, USA. OSHA. 1994. General description and discussion of the levels of protection and protective gear. 1910.120 App B. Last updated August 22, 1994. Available at: http://www.osha.gov/pls/ oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9767 WMO (World Meteorological Organization), 2011. Scientific Assessment of Ozone Depletion: 2010 , Global Ozone Res earch and Monitoring Project

— Report No. 52, 516 pp., Geneva, Switzerland, 2011.