Phone: Lindsay Hill, CIH: (205) 640-7305 (Direct); (205) 937-3321 (Cell) 

 William Garvin, CIH: (205) 419-5124 (Direct); (205) 903-5106 (Cell) 

E-mail: info@directcih.com 

70 Cherokee Lane 

Pell City, Alabama 35128 

http://directcih.com 

DIRECTCIH

INDUSTRIAL HYGIENE MONITORING INVESTIGATION 

& 

OCCUPATIONAL EXPOSURE ASSESSMENT 

OF 

2-BROMO 3,3,3-TRIFLUOROPROPENE 

FOR 

AMERICAN PACIFIC CORPORATION, HALOTRON DIVISION 

CEDAR CITY, UTAH 

Prepared for Bradford Colton, Research Engineer 

3883 Howard Hughes Pkwy, Suite 700 

Las Vegas, Nevada 89169 

By Lindsay R. Hill, CIH 

DirectCIH, LLC 

November 27, 2013 
0 

DIRECTCIH

Table of Contents

1.0 SITUATION ............................................................................................................... 1

2.0 GOALS .................................................................................................................... 2

3.0 METHODS ................................................................................................................ 2

3.1 Preliminary Information ..................................................................................... 2

3.2 Exposure Activities ............................................................................................ 5

3.3 Simulation Monitoring ........................................................................................ 8

3.3.1 Spill From Disconnection of Liquid Fill Fitting Procedure Simulation .............. 9

3.3.2 Sample Bottle Filling Procedure Simulation ................................................. 10

4.0 RESULTS ............................................................................................................... 10

5. RECOMMENDATIONS ............................................................................................. 16

6. QUALIFYING STATEMENT ..................................................................................... 17

7. CLOSING .................................................................................................................. 18

APPENDICES 

APPENDIX A – SAMPLING INFORMATION, CALIBRATION DATA 

APPENDIX B – AIR MONITORING INVESTIGATION WITH R123 IN BLDG 24C AT 

THE AMPAC CEDAR CITY, UTAH FACILITY 

APPENDIX C—AIR MONITORING INVESTIGATIONS WITH R123 AT THE AMEREX 

TRUSSVILLE, ALABAMA FACILITY 

 
1 

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November 17, 2013 

Bradford Colton, Research Engineer 

American Pacific Corporation 

Halotron Division 

3883 Howard Hughes Pkwy 

Suite 700 

Las Vegas, NV 89169 

1.0 SITUATION 

American Pacific Corporation (AMPAC) has developed a new halogenated hydrocarbon 

compound to be used as a clean agent fire suppressant alternative to Halon 1211. The 

new product being researched is known as Halotron BrX, or BTP, and has the chemical 

name 2-Bromo-3,3,3-trifluoro-1-propene, and CAS number 1514-82-5. This product is 

similar in physical properties to AMPAC’s existing Halotron I, or HCFC Blend B, clean 

agent that is an alternative to Halon 1211 and has been sold in UL listed extinguishers 

since 1996. The primary ingredient of Halotron I is R-123, or HCFC-123, and comprises 

greater than 95% wt. of the composition. Due to similarities in application and physical 

properties of Halotron I and BTP, it was anticipated that Halotron I would be a good 

surrogate for BTP. Separate monitoring studies of R-123 and BTP were completed 

during typical handling operations and a comparison of R-123 and BTP was made in 

order to determine whether a correction factor might be applied to the R-123 data to 

estimate what the handling exposures would be for BTP. 

This industrial hygiene investigation was done in order to (1) estimate the level of 

operator exposure to R-123 during tasks where it is poured or spilled, (2) estimate the 

level of operator exposure to BTP in the same work setting, (3) determine if the R-123 

monitoring data is predictive of BTP levels, and (4) use this testing as part of the 

process fulfilling the requirements under the Toxic Substances Control Act (TSCA). 

Air monitoring investigations for this and previous related investigations, presented in 

the Appendices, were done over a range of work settings, time periods, locations, and 

employees for the R-123. Study locations included the AMPAC facility in Cedar City, 

Utah, where 1⁄2 ton steel Halotron cylinders are sampled and filled, and their contents 

tested, and at the Amerex facility in Trussville, Alabama where several portable 

extinguisher sizes are filled. Sampling and analysis was done on-site with a portable 

dispersive infrared spectrophotometer that was placed or held in the immediate work 

area, or, where possible, near the breathing zone of the operator during normal work. 
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This report describes the air monitoring and results of the R-123 and BTP during the 

execution of different tasks at the Cedar City AMPAC facility. An effort is made to 

generate a correction factor to apply to the R-123 averages to predict BTP 

concentrations that would be found under similar conditions, and to see if tentative 

occupational exposure levels (OELs) for BTP are met. 

 

 

2.0 GOALS 

Monitoring events took place between March and October of 2013. They were done 

both to assess worker exposure to R-123 during various work practices and periods, 

and as part of a larger effort, to compare the behavior and consequent airborne 

concentrations of R-123 with BTP in exposure simulations. Since there are similarities 

in the physical properties of the two compounds, it was hoped that by duplicating work 

practices as closely as possible during monitoring events with first one compound, then 

the other, it might be possible to assume the same exposures for the same types of 

operations. If there were differences, perhaps a compensation or adjustment value 

could be determined. This could then be applied to the R-123 monitoring levels 

previously and more easily determined in order to estimate BTP levels in the same 

situation. The primary goal is that ideally, a valid, though tentative OEL for BTP will 

emerge from this work. 

 3.0 METHODS 

3.1 Preliminary Information 

Lindsay Hill, a certified industrial hygienist (CIH) with DirectCIH, visited the AMPAC 

Cedar City, Utah Halotron facility during the week of October 28th, 2013. Over three 

days Mr. Hill logged over 10 hours of air monitoring during R-123 and BTP handling 

in Building 24C. The R-123 liquid is regularly transferred via high pressure lines with 

quick-connect fittings from a ~75,000 lb. capacity insulated permanent tank in the 

back room of the building (it is filled once or twice a month from a tank truck) to 1⁄2 

ton steel cylinders (1000 lb. water capacity, with capacity of up to 1,200 lbs of 

Halotron I) designated by DOT as 4BW260 vessels. Occasionally 500 lb and 

smaller cylinders are also filled. Used cylinders are routinely sampled and rinsed 

internally with R-123, and the contents analyzed, before refilling for shipment to 

various fire extinguisher companies for commercial and retail distribution. The R123 is mixed with smaller amounts of CF4 and Argon, less than 7% wt, in the 

cylinders for optimal pressure, fill level, and application performance characteristics. 
3 

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The analyzer used for air monitoring was a Thermo Scientific Miran Sapphire 

Ambient Air Analyzer, Model 205A, Serial Number S00089. The instrument uses 

single beam dispersive infrared (IR) spectrophotometry in a portable unit with factory 

calibration of the gases under study. Sample air enters an extendable probe at 14 

liters per minute. A microprocessor automatically controls the analysis, processes 

the measurement signal, and calculates the absorbance values. Internal 

adjustments were made for humidity, elevation, and reference compensation (to 

reduce electronic drift) using algorithms. The instrument is zeroed using activated 

charcoal cartridges prior to each use. The compound’s absorbance wavelength and 

the IR beam path length used for each log are manually selected to minimize cross 

sensitivities and maximize sensitivity to the compound of interest, respectively. The 

electrical supply is generally provided by an internal battery, but because of the 

sample duration and a limited need for mobility this application used 110 volts AC 

from a wall outlet. 

Thermo Scientific states that the analytical accuracy for R-123 is within 10% of the 

reading with a detection limit of 0.07 ppm. For BTP the instrument reading was 

within 1.5% of the calibration value with a detection limit of 0.17 ppm. Factory 

inspection, calibration and maintenance of the instrument were performed 

immediately prior to this investigation by Thermo Scientific. The documentation of 

this information is detailed in Appendix A following this report. 

The instrument analyzes twice per second, and the data are averaged every ten 

seconds. In the configuration used here, one data point (in this case compound 

concentration in parts per million, ppm) was stored in the analyzer every 30 

seconds. This information was then downloaded and is presented in tabulated 

summaries below, and also in annotated graphs of concentration over time. All of 

the logged data from earlier investigations of the R-123 is presented in graphs in 

Appendices B and C following this report. 

Building 24C consists of a small front office, the main room where this monitoring 

event was conducted, and a back room where the large R-123 tank is housed. The 

main room is approximately 70,000 cubic feet in volume. There is a large bay door 

and office doors in the front (closed during monitoring, but which may or may not be 

open during operations), and a door to the back room (open during monitoring, as is 

normal during operations). Back room doors to the outside were closed during 

monitoring, as is normal. The operator does his work with the cylinders positioned on 

a floor scale next to a work table that is towards the back of the main room. Figure 

1, on the following page, shows a 1⁄2 ton cylinder on the scale, work table, and 

analyzer. 
4 

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Figure 1: Layout of work area in Building 24C showing IR analyzer, 1⁄2 ton cylinder, and 

work table with quick connect fittings. 

There are no windows, but a 32 inch diameter propeller style fan operates 

continuously moving air from the main room into the back room to provide air 

movement for the operator, and to keep temperatures above freezing in the back 

room. The fan is approximately 14 feet from the operator’s primary activities when 

working with R-123 or BTP. Measurements were made at 21 locations within the fan 

opening with an impeller anemometer to determine average flow. Average air flow 

was calculated that 5736 cubic feet of air are moved per minute, and that 4.9 air 

changes per hour take place in the main room. 
5 

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Two large ceiling mounted thermostatically controlled heaters with blower fans are 

on one side of the main room. One is about 12 feet from the work table where the 

operator stands to conduct filling activities for the cylinder on the scale, or will sit 

behind to complete paperwork. The heaters are tilted down, and the heater closest 

to the work area and table is oriented towards the back of the main room so that 

there is a directed current of air from the heater past the operator, and out through 

the fan to the back room while in operation. Due to cold weather during the 

monitoring event the heater fan would intermittently turn on and off. The warm air 

movement increased dispersal and evaporation of product. 

3.2 Exposure Activities 

The operations at the Cedar City, Utah AMPAC Halotron facility are typically 

performed by a single operator. Air monitoring focused on the operator’s work area 

and specifically, the operator breathing zone during activities involving material 

handling and cylinder preparation. The operator may also complete a portion of the 

day in the front office, which was shown to be clear of any halogenated agent 

concentrations. The operator’s protective equipment includes steel toed boots, eye 

protection, and thick nitrile gloves when handling product or product equipment. 

After discussions between Halotron engineering, plant personnel, and AMPAC’s 

toxicologist consultant working with the BTP, it was determined that five functions 

occur in Building 24C during the handling of product: 

(1) Preparing new containers – transferring agent in and rinsing (rinsed agent 

transferred in closed system to waste tank) – closed system, 

(2) Transferring base (a mixture of R-123 and Ar) – transferring base through hoses 

into bulk tank – closed system, 

(3) Transferring gases (CF4 or Ar) - transferring gas through hoses into bulk tank – 

closed system, 

(4) Sampling – transfer of liquid into bottles - open system, and 

(5) Venting – returned containers need argon pressure vented to be refilled – this 

used to be done with a vacuum hood placed above the valve, but now uses a direct 

hose connection that vents the tank outside the building– closed system. 

It was originally assumed that since (4) sampling was the only open system 

operation among these activities, it would be the only one with potential exposure. 
6 

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After observing the operator conduct the various operations, it was quickly realized 

that even though quick-connect fittings were fast and convenient, product was lost 

due to adaptors used to fit the quick connect to the cylinder valves. The 1⁄2 ton 

cylinders used to store final product have a vapor and liquid valve with a CGA 660 

fitting. Quick-connect fittings are attached to these valves using CGA and pipe 

fittings. When liquid transfer operations were complete, the removal of the fill fitting 

connected to the liquid valve would squirt small amounts of product when 

disconnected, or spill product when tilted after disconnecting. Once disconnected, 

the fill fitting is returned to its storage location on the side of the work table. The 

product, whatever was being transferred, would spill onto the top shoulder of the 1⁄2 

ton cylinder and run down, or splash directly onto the concrete floor. As the 

shoulder of the bottle is close to breathing zone height and the product evaporates 

extremely fast (refer to Table 5), the opportunity for inhalation was frequent. 

During the monitoring, it was determined that a ball valve and quick connect on the 

liquid transfer line were worn out causing additional airborne concentrations. The 

operator indicated that it was difficult to determine a timely maintenance schedule for 

these, which were replaced prior to the air monitoring events. Note fittings in the 

bottom corner of Figure 2. 

 
7 

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Figure 2: Operator simulating spill from quick connect fitting onto shoulder of 1⁄2 ton 

cylinder. Note relation of heater, breathing zone of operator, spill location, and monitor 

probe (bottom). Air flow is from the heater towards the monitor probe. 

 
8 

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3.3 Simulation Monitoring 

There were several choices in selecting an exposure scenario to monitor. The two 

scenarios which result in the highest exposures were selected. The first scenario 

was designed to simulate the sample bottle filling operation, as this is an open 

system, an obvious source of some exposure, and because it is done frequently. 

The second exposure scenario involved simulating a spill from the disconnection of 

the liquid fill fitting, which resulted in a release of material onto the cylinder shoulder. 

The operator estimated the volume of product typically lost when disconnecting the 

fill fitting. During the monitoring for each scenario, the duration of peak exposure 

was a matter of a few seconds. 

Figure 3: 30 ml sample and squeeze bottles. 

Several issues arose during monitoring. It was determined that there was some 

cross sensitivity between the two compounds, so that when the analyzer was set to 

the absorbance wavelength of R-123, it would also respond to a lesser degree to the 

BTP. 

A second and larger problem was that the R-123 left an airborne residual 

background level after using it. The more it was used, the higher the background 

level became. Product transfer on Monday, October 28th, left standing liquid within 

the liquid fill fittings stored at the work table. Evaporation caused the background 

level to go from 0.18 ppm initially to about 8 ppm in the main room on Tuesday, 

October 29th. The average concentrations from the analysis of R-123 could then not 

be used in establishing a correction factor for BTP, but was very useful in identifying 
9 

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sources of exposure. A similar background level was seen in air monitoring at the 

Trussville, Alabama facility, but the source(s) were not as well understood because 

other halogenated fire extinguishing agents handled were in the vicinity of the 

Halotron I fill line. Airborne concentrations of R-123 had diminished to premonitoring levels by the next morning, and all of the logged data from October 30th

was useful because background levels remained low. 

The heater fan also caused airborne levels of product to fluctuate during monitoring, 

and it could not be determined when the thermostatic control would turn the unit on, 

so monitoring on October 30th was done with the heat shut off. 

Each of the two simulations was completed twice, once using the R-123 and again 

using the BTP. Each simulation event, i.e., sample pour or spill, was repeated four 

or five times with the analyzer probe positioned on the edge of the work table down 

draft from the operator’s face. The distance was about four feet laterally and 

eighteen inches below his breathing zone. The product being poured or spilled was 

only one or two feet from his face (and also just below), but not in an up or down 

draft direction. 

A final pour/spill was completed in each simulation event with the probe within a foot 

of the operator’s face to see how the compound concentration differed from the work 

table position of the probe. The graphs below illustrate the concentration over time 

during the simulations and annotate the activity. Figure 2 above shows the spill 

simulation. 

3.3.1 Spill From Disconnection of Liquid Fill Fitting Procedure Simulation 

Spillage from the disconnection of the liquid fill fitting was the second exposure 

scenario evaluated. In order to transfer liquid product into the 1⁄2 ton cylinders, a 

liquid fill fitting with a male Parker quick-connect is attached to the CGA 660 

fitting on the cylinder. A transfer hose leading from the 75,000 lb. bulk tank is 

equipped with a female quick-connect. The male quick-connect that is attached 

to the cylinder is removed once liquid transfer operations are complete. 

Disconnection of this fitting results in a small amount of product spillage onto the 

shoulder of the cylinder. 

When monitoring the R-123 spills, the cylinder fitting was tilted onto the shoulder 

of the cylinder during disconnection. The fitting was then set, vertically, in its 

storage location on the side of the work table. The simulation with R-123 and 

BTP was completed by filling 30 ml bottles with the estimated amount of liquid 

that spilled from the fitting, about 4 ml. At 5-minute intervals, the 4 ml of product 

(contained in each 30 ml bottle) was poured onto the shoulder of the 1⁄2 ton 

cylinder. Figure 2 above shows the spill simulation. 
10 

DIRECTCIH

These measurements were completed on October 30th and the heater was 

turned off. 

3.3.2 Sample Bottle Filling Procedure Simulation 

Sampling of final product is completed by attaching the sampling port onto the 

liquid valve of the 1⁄2 ton cylinder, transferring liquid into a 500 ml Nalgene bottle, 

and then into a 30 ml glass bottle. These two bottles are then sent to the lab for 

quality analysis. When simulating this event, which was performed with both R123 and BTP, the filling of a sample bottle was limited to a single bottle using a 

squeeze bottle to mimic the transfer of liquid from a sampling port. Since the 

intent of this simulation was to determine a comparison between R-123 and BTP, 

it was desirable to closely mimic a standard procedure. The diameter of the 

squeeze bottle orifice was increased until the flow rate was about the same as 

the flow rate coming from the sample port. Figure 3 shows the 30 ml sample and 

squeeze bottles used for the simulation of sample bottle filling. 

This testing was completed on October 29th. The heater fan operated 

intermittently. 

4.0 RESULTS 

The following four graphs and accompanying tables present the logged data from each 

of the four approximately 30 minute simulation events discussed above. Figure 4 and 

Table 1 correspond to the R-123 sampling bottle filling. Figure 5 and Table 2 

correspond to the BTP sample bottle filling simulation. Figures 6 and 7 and their 

corresponding Tables, 3 and 4, likewise, represent results from the R-123 spills and 

BTP simulation spills. The operator breathing zone peaks in the last three monitor logs 

were not included in the calculated average exposure level to reduce variability (note 

that in Table 1, the operator breathing zone concentration was similar to the other four 

peaks thereby not increasing variability, and allowed for five peaks in calculation of an 

average concentration). Operator actions, heater operation, and other factors influence 

the variability between peaks within each simulation. 
11 

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Figure 4: R-123 sample bottle filling. Note residual background level of about 8 ppm. 

Table 1. R-123 Sample Bottle Filling Data from 33 Minute Log 

Peak 1 Peak 2 Peak 3 Peak 4 Peak 5 

Max level 

67.6 ppm 

Max level 

47.3 ppm 

Max level 

31.5 ppm 

Max level 

31.3 ppm 

Max level 

29.9 ppm 

Above 10 ppm 

120 seconds 

Above 10 ppm 

90 seconds 

Above 10 ppm 

120 seconds 

Above 10 ppm 

120 seconds 

Above 10 ppm 

90 seconds 

6% of log time 4.5% of log 

time 

6% of log time 6% of log time 4.5% of log 

time 

179% of peak 

average 

125% of peak 

average 

83% of peak 

average 

83% of peak 

average 

79% of peak 

average 
12 

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Figure 5: BTP sample bottle filling simulation. 

Table 2. BTP Sample Bottle Filling Data with Probe at Table 

33 Minute Log 

Peak 1 Peak 2 Peak 3 Peak 4 Peak 5 

Max level 

21.2 ppm 

Max level 

24.6 ppm 

Max level 

17.0 ppm 

Max level 

27.8 ppm 

Max level 

20.0 ppm 

Above 10 ppm 

 30 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

30 seconds 

Above 10 ppm 

30 seconds 

1.5% of log 

time 

3% of log time 3% of log time 1.5% of log 

time 

1.5% of log 

time 

96% of peak 

average 

113% of peak 

average 

77% of peak 

average 

126% of peak 

average 

90% of peak 

average 
13 

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Figure 6: R-123 spills from the quick disconnect fitting 

Table 3. R-123 Fitting Spills Data with Probe at Table from 32 Minute Log 

Peak 1 Peak 2 Peak 3 Peak 4 Peak 5 

Max level 

11.5 ppm 

Max level 

42.3 ppm 

Max level 

32.1 ppm 

Max level 

32.9 ppm 

Max level 

20.2 ppm 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

3% of log time 3% of log time 3% of log time 3% of log time 3% of log time 

41% of peak 

average 

152% of peak 

average 

115% of peak 

average 

118% of peak 

average 

73% of peak 

average 
14 

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Figure 7: BTP spill simulation from 30 ml bottles onto cylinder shoulder. 

Note: 4.2 ppm average based on min + max values; 5.0 ppm value used below 

Table 4. BTP Fitting Spills Simulation Data with Probe at Table 

34 Minute Log 

Peak 1 Peak 2 Peak 3 Peak 4 Peak 5 

Max level 

14.8 ppm 

Max level 

45.4 ppm 

Max level 

62.6 ppm 

Max level 

21.4 ppm 

Max level 

14.5 ppm 

Above 10 ppm 

30 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

60 seconds 

Above 10 ppm 

30 seconds 

Above 10 ppm 

60 seconds 

1.5% of log 

time 

3% of log time 3% of log time 1.5% of log 

time 

3% of log time 

47% of peak 

average 

143% of peak 

average 

197% of peak 

average 

68% of peak 

average 

46% of peak 

average 
15 

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A summary of the tabulated statistics from the graphed and tabulated data above 

indicates differences in the exposures from activities and compounds and are shown 

below: 

Table 5. Summary of Data from 30 Minute Simulation Logs 

Simulation 

Event 

Peak 

Levels, 

ppm 

% of Log 

as Peak 

( >10 ppm)

Average 

Levels, 

ppm 

Standard 

Deviation 

Vapor 

Pressure 

@20°C, 

mm Hg 

Vapor 

Density 

@20°C 

max avg (g/L) 

R-123 

Sampling 

67.6 37.8 27% 15.1* 13.3 580 5.14 

 

BTP 

Sampling 

27.8 23.4 11.5% 7.9 16.1 510 7.27 

R-123 Spills 42.3 27.8 18% 11.1 10.6 

BTP Spills 62.6 31.7 13% 5.0 9.7 

*without background removal – subtracting 4 ppm is commensurate with BTP 

Sampling log background 

Note: Peak level calculations do not include breathing zone peak 

The averaged concentrations and standard deviation of values reveal differences 

between the scenarios. Higher averages during sampling, as opposed to spills, are a 

result of a high background level for the R-123, and longer periods of exposed product 

in the air. As the multiple peaks of varying concentrations during the performance of 

tasks will attest, these graphs do not lend themselves to interpretation in terms of 

central tendency, but the standard deviation values are significantly higher for the 

sampling events. There is greater variation in exposure levels during sampling. It is 

also likely that many different activities will exhibit this variation in exposure levels. 

The percent of the log as a peak and the averaged log concentrations reveal differences 

between the compounds. The greater vapor pressure of R-123 results in longer and 
16 

DIRECTCIH

higher concentration breathing zone exposures. The greater vapor density of BTP 

results in its rapid removal to low areas, with less inhalation time and concentration. 

With background adjustment, the average R-123 levels are 141% higher than the BTP 

levels during the sampling scenario. The average R-123 levels are 222% higher than 

the BTP levels during the spill events. As a first estimate, if the average level of R-123 

that is used is 222% higher than BTP, then a multiplier of 0.45 applied to an R-123 level 

would make BTP levels equivalent. 

Appendix B contains personnel exposure monitoring of R-123 levels during actual 

operations at the Halotron production facility in Cedar City, Utah, for production of the 

Halotron I fire extinguishing agent. Depending on the operations taking place, the 

average exposure levels were between 5.3 and 13.8 ppm of R-123 for a 10 hour shift. 

Assuming similar handling of BTP, using the 0.45 multiplier would result in average 

levels between 2.4 and 6.2 ppm for a 10 hour shift. 

Appendix C contains personnel exposure monitoring of R-123 during actual operations 

of filling UL listed portable extinguishers with the Halotron I fire extinguishing agent at 

the Amerex facility in Trussville, Alabama. The average exposure level was 2.2 ppm of 

R-123 for a 10 hour shift. The procedure to transfer extinguishing agent into a fire 

extinguisher and pressurize it with argon or nitrogen to its operating pressure would be 

the same for Halotron I and BTP. Therefore, while exposure controls could vary, 

operations would be similar for these products. Using the 0.45 multiplier would result in 

an average exposure level for BTP of 1.1 ppm for a 10 hour shift. 

5. RECOMMENDATIONS

DirectCIH presents the following recommendations: 

1. This monitoring reveals much of the nature of exposure between these 

compounds. While a correction factor is proposed here, the amount of variation 

in the values from the simulations does not lend itself to a particularly valid 

correction or predictive factor that can be used for the BTP. Standard deviations 

do not approach 100% of the averages, so the correction factor should remain 

below 1.0. More data from simulations are needed. 

2. By taking advantage of the vapor density of BTP, engineering controls such as 

low-lying point source ventilation should be very effective in mitigating exposure. 
17 

DIRECTCIH

3. Rigorous adherence to a conservative maintenance schedule for the product 

transfer equipment, i.e. quick connect fittings, will reduce exposure substantially. 

4. Ceiling level OELs will be exceeded by concentration spikes that occurred during 

monitoring, and must be considered. 

5. The proper placement of the operator in relation to the source of product and the 

heater fan or other sources of air movement while doing his work will reduce 

exposure. 

6. Expanding on #5 above, any changes that physically lower the product sources 

further from and below the operator’s breathing zone will reduce exposure levels. 

6. QUALIFYING STATEMENT 

DirectCIH presents the findings, conclusions and recommendations, herein, which are 

based solely on the conditions observed during the date the sampling program was 

conducted. Additionally, DirectCIH does not make any representation or projection as 

to past conditions or future exposures and does not extend its findings to areas outside 

of the statistical representation of the completed investigation. 

The findings and conclusions of this report are not scientific certainties, but rather, 

probabilities based on professional judgment concerning the significance of the data 

gathered during the course of the investigation. 

Sampling and analytical results are limited in that they represent concentrations at the 

time of sample collection only. Changes in operating procedures, ventilation, 

temperature, occupancy, procedures, equipment, sources, products used, and other 

conditions may cause variations in anticipated airborne concentrations. 

This report has been prepared for the exclusive use of the client. This report and its 

analytical results, findings, conclusions, and recommendations, either in part or its 

entirety is not to be used by any other party without prior consent of DirectCIH or the 

client. Any use thereof, other than the sole benefit of DirectCIH or the client, shall be 

deemed wrongful and may cause irreparable injury to DirectCIH or the client. 
18 

DIRECTCIH

7. CLOSING 

DirectCIH appreciates the opportunity to assist with your health and safety needs. 

Please contact us if there are any questions or comments regarding this investigation. 

Sincerely, 

Lindsay R. Hill, CIH 

Principal, DirectCIH

 
19 

DIRECTCIH

APPENDIX A

SAMPLING INFORMATION, CALIBRATION DATA 
20 

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21 

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22 

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23 

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APPENDIX B 

AIR MONITORING INVESTIGATION WITH R123 IN BLDG 24C 

 AT THE AMPAC CEDAR CITY, UTAH FACILITY 
24 

DIRECTCIH

November 17, 2013 

Bradford Colton, Research Engineer 

American Pacific Corporation 

Halotron Division 

3883 Howard Hughes Pkwy 

Suite 700 

Las Vegas, NV 89169 

Re: Determination of R-123 Levels in Building 24C, Cedar City, Utah Facility 

On October 28th and 29th, 2013, Lindsay Hill, an industrial hygienist with DirectCIH, 

visited American Pacific Corporation’s (AMPAC) Halotron facility in Cedar City, Utah. 

The visit was made to monitor the operator’s exposure to R-123, also known as 

Halotron I during product transfer operations. The chemical name is 2,2-dichloro-1,1,1-

trifluorothane. 

The R-123 is a fire suppressant raw material that is transferred as a liquid under 

pressure into 1⁄2 ton cylinders, which are then shipped to fire extinguisher 

manufacturers. The Halotron operator conducts cylinder preparation, sampling, and 

filling of cylinders with the Halotron I, or HCFC Blend B. The primary ingredient of 

Halotron I is R-123, or HCFC-123, and comprises greater than 95 %wt. of the 

composition. The remaining portions of the composition are comprised of CF4 and 

argon (Ar). A day of operations may consist of entirely filling of final product cylinders or 

preparation of return cylinders. 

The probe from the analyzer was held near the operator’s breathing zone, or set at the 

edge of his work table. It was generally within three or four feet of operator’s face 

during his work. 

 

A Thermo MIRAN SapphIRe model 205A dispersive infrared spectrophotometer (IR) 

was used to determine the levels of the R-123. The analyzer was factory calibrated with 

R-123, and could be monitored individually or with other compounds in the on-board 

library. Annual calibration documentation is in Appendix A. 

The analyzer performs two analyses per second. After startup it was zeroed and 

warmed up for about 1⁄2 hour prior to logging. The logging configuration generated an 

averaged data point, or concentration in parts per million (ppm) every 30 seconds. 

Levels were logged over two periods on consecutive days, each lasting about four 

hours. The data were graphed as concentration over time, with annotations giving 

average and maximum values and changes in activity when they took place. The 

graphs are presented below. There were numerous high concentration spikes over the 
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logging periods. 

The first graph, Figure 1, taken on the morning and early afternoon of October 28th, was 

from air monitoring conducted while the operator sampled and filled seven cylinders 

with base, which is a mixture of R-123, argon, and CF4. In order to transfer liquid 

product into the 1⁄2 ton cylinders, a liquid fill fitting with a male Parker quick-connect is 

attached to the CGA 660 fitting on the cylinder. A transfer hose leading from the 75,000 

lb permanent bulk tank is equipped with a female quick-connect. However, the male 

quick-connect that is attached to the cylinder is removed once liquid transfer operations 

are complete. Disconnection of this fitting results in a small amount of product spillage 

onto the shoulder of the cylinder. The transfer hose leaked at the ball valve between 

the filling of cylinders 2 and 3, causing a 268 ppm concentration spike of R-123. The 

valve was replaced and the average concentration over the logging period without that 

spike was 5.3 ppm. 

The second graph, Figure 2, taken early the next morning, was logged during and after 

the preparation of return cylinders. In order to reuse empty cylinders that are returned 

from customers, a small amount of base is added to the cylinders through the cylinder 

vapor valve. This rinses the interior of the cylinder and provides a level of liquid product 

that may be removed to check for physical contaminants and moisture contamination. 

Product from the cylinder was transferred to open sample bottles and a small amount of 

spillage from the sample port took place. After this, the liquid fill fitting attached to the 

vapor valve was removed, which also resulted in about 4 ml of spillage. These 

spillages all contributed to frequent concentration spikes and a buildup of a high (10-15 

ppm) background concentration, which only slowly subsided. The average 

concentration over the log was 13.8 ppm. 

Note that high concentrations of R-123 are exhibited during early work (October 28 and 

29, 2013) These higher concentrations of R-123 occurred because the operator was 

attempting to create a worst case scenario, and residual levels were amplified due to 

liquid product remaining in fittings (this situation was rectified). 
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Figure 1: R-123 levels logged in Building 24C on October 28, 2013 
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Figure 2: R-123 levels logged in Building 24C on October 29, 2013 

Please feel free to contact DirectCIH if you have any questions regarding this work. 

Sincerely, 

Lindsay R. Hill, CIH 

Principal, DirectCIH LLC 
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APPENDIX C 

AIR MONITORING INVESTIGATIONS WITH R123 

 AT THE AMEREX TRUSSVILLE, ALABAMA FACILITY 
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March 25, 2013 

Will Yarbrough, Safety Director 

Fred Goodnight, VP Engineering 

Amerex Corporation 

7595 Gadsden Highway 

Post Office Box 81 

Trussville, Alabama 35173-0081 

Re: Determination of Halotron I Levels at the Fill Station, Dept. 04 

On March 13, 2013, Lindsay Hill, an industrial hygienist with DirectCIH, visited the 

Amerex facility in Trussville, Alabama. Consideration of a new formulation of halon 

extinguisher lead to a need to quantify, to the best extent possible, the exposure levels 

among personnel filling the extinguishers at the facility. There are several uncertainties 

in establishing time-weighted average exposures the employees receive. They include 

working ten hour shifts, the changing of bottle sizes and extinguisher volumes during a 

shift, occasional spikes in the halon concentration, attributes particular to the operator, 

and operator movement in the area. The new halon formulation being considered 

(Halotron II), while brominated rather than chlorinated, has physical and chemical 

properties similar to the current halon, dichlorotrifluoroethane. Therefore, it was decided 

that a properly conducted air monitoring effort of the current halon would give a good 

approximation of the exposure levels encountered with the new halon formulation. 

A Thermo MIRAN SapphIRe model 205A dispersive infrared spectrophotometer (IR) 

was used to determine the levels of the current halon. Levels were logged over several 

hours while bottles were being filled. The analyzer’s on-board library includes this 

halon. The instrument is factory calibrated annually. Sissy Clark, the area supervisor, 

was contacted, and the bottle filling operation and air monitoring plans were discussed 

with her in detail. Ekerica Bates was the operator at the halon filling booth, and she was 

briefed as to the monitoring of her breathing zone at the booth during her work. 

The booth, shown in the photographs below (and showing the analyzer probe on Will’s 

left), has a large (~1.5 square meter) front door that slides up when the transfer and 

filling operation takes place, which is roughly about every two minutes with the five 

pound bottles. The operator bends forward with the upper body fully inside the booth 

during the task. The door is then slid down and closed during the filling process, which 

takes place on a shaker table. The filling booth has numerous small openings to allow 

cables, gas lines, etc. access, and the analyzer probe was inserted through one of 
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these openings in the ceiling. Because of the openings there was a background level of 

the halon of about three ppm in the immediate area before operations even began for 

the day. The probe from the analyzer was generally within one foot of Ms Bates face 

during her work with the door open; she is diminutive, and the probe could have been 

several inches lower. 

The analyzer performs two analyses per second. After startup it was zeroed and 

warmed up for about 1⁄2 hour prior to logging. The logging setup took one averaged 

data point every minute, after every 120 analyses. Two periods of time were selected 

from the data, covering between one and two hours before, and then after lunch. The 

data were graphed as concentration over time, with annotations giving average and 

maximum values and changes in activity when they took place. The graphs are 

presented below. There were several high concentration spikes over the logging 

period. It is speculated that the gas line connection may occasionally be released prior 

to complete valve closure to cause this, but there may be another explanation. 

The average concentration over the logged intervals was about seven to eight ppm, with 

a maximum of at least 50 ppm. Higher values were indicated, but the analyzer was set 

to identify levels only up to about 15 ppm. Discussions with Bob Francis of Thermo 

Scientific about this indicated that the analyzer has no significant drop-off in accuracy 

until it exceeds about 50% of the set range; beyond that, concentrations may be 

inaccurate, so this data has been disregarded. Note that these values are from inside 

the booth, and the operator only spent part of her time there. 

Please feel free to contact DirectCIH if you have any questions regarding this work. 

Sincerely, 

Lindsay R. Hill, CIH 

Principal, DirectCIH LLC 
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0

2

4

6

8

10

12

14

16

18

9:179:219:259:299:339:379:419:459:499:539:57

10:0110:0510:0910:1310:1710:2110:2510:2910:3310:3710:4110:4510:4910:5310:5711:0111:05

parts per million

time

dichlorotrifluoromethane levels at halotron I fill

station, dept. 04, morning

background level 3

max 16

filling 5 lb

avg level
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May 9, 2013 

Will Yarbrough, Safety Director 

Fred Goodnight, VP Engineering 

Amerex Corporation 

7595 Gadsden Highway 

Post Office Box 81 

Trussville, Alabama 35173-0081 

Continuing Evaluation: Exposure of Personnel to Halotron I, Fill Station, Dept. 04 

On May 1st and 2nd, 2013, Lindsay Hill, an industrial hygienist with DirectCIH, revisited 

the Amerex facility in Trussville, Alabama to further investigate exposures initially 

monitored last March 13th. At that time a portable IR analyzer was used for several 

hours to determine concentrations of an extinguishing agent inside the fill booth. As 

described in the report of March 25th, the operator enters the booth every few minutes in 

order to change out extinguisher bottles in the filling process. The monitoring results 

were unexpected. There were higher than expected background and average levels 

present, and occasional concentration spikes beyond the range of the analyzer setting. 

The monitoring event left several questions about acquiring a representative measure of 

employee exposure, such as: 

What was the proportion of time spent inside the booth vs outside? 

How far from the booth did the operator go, and did that influence exposure? 

What was the averaged exposure, from both inside and out? 

What was the origin of the background Halotron levels? 

Was there a difference in Halotron levels based on type of bottle being filled? 

This report attempts to answer these questions, and present a reasonable estimate of 

average exposure levels over a 10 hour shift for those working at the fill booth. 

To determine the level of Halotron I exposure throughout the course of the shift, it was 

first necessary to find out what proportion of time is spent inside the booth vs outside. 

Over two 15 minute intervals on two days a stopwatch was used (discreetly) and the 

percentage of each period inside vs outside was calculated. The percentages of the 

two were then averaged. If the employee is not disturbed the proportions are very 

consistent; 7% of the time at the station is spent with the door open, and the remaining 

93% with the door closed. Note that this was measured during the filling of 11 lb. 

bottles. 
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The issue of employee movement away from the station and the subsequent change in 

exposure levels is also dependent on bottle size. The fill station operator has two 

rest breaks, lunch, and bathroom breaks during the shift like every other employee. The 

only other regular cause to leave the fill station is to get additional parts, which are 

about 20 feet away. Sissy Clark, the area supervisor, was asked what amount of time 

was spent during a 10 hour shift on this task. She estimated perhaps 15 minutes with 

the large bottles and up to (but probably less than) one half hour with the small bottles, 

since they need replacements more frequently. This is consistent with the industrial 

hygienist’s observation. Though momentary and infrequent concentration spikes at the 

fill booth raise the average slightly in that immediate area, the proportion of time spent 

at any substantial distance getting parts is about 2% to 4% of the shift. Even if a 

concentration spike occurs during the moment the employee is away, in most cases it is 

inconsequential to her overall exposure. 

To estimate the overall exposure level of the fill booth operator, about nine hours of air 

monitoring was logged on May 1st and 2nd, with about 6.5 hours logged immediately 

outside the booth in the worker’s breathing zone, and about 2.5 hours logged inside the 

booth. The logged data were graphed, annotated, and are presented below. Large 

fans were operating continuously, each between about 10 and 20 feet from the door of 

the fill booth, and located opposite one another so that blowing air converged on the 

operator’s work area. As a result, even when the fill booth door was open the intake at 

the analyzer probe was buffeted with air from outside the immediate area. Using the 

7% vs 93% proportions described above, and the averages from the logs, the average 

concentration was calculated as follows: 

93% X 0.3 ppm + 7% X 27.6 ppm = 2.21 ppm average from inside and out. 

The logged readouts from the IR analyzer present minimum, maximum, and average 

values for every analysis, that is, every 0.5 seconds. All values used here are the 

maximum values, as they are the most conservative and if in error will be in the 

direction producing the safest response or control. This makes the momentary maxima 

(the big peaks on the graph) look much greater than if average or minimum values had 

been used, but does not appreciably affect the long-term average. 

It was suggested that the background levels of Halotron I indicated by the IR analyzer 

were not from the product at the fill booth; rather, that they originated nearby where a 

chemically similar halon extinguisher is kept. Because the IR frequencies use the bond 

energies in a molecule to identify unknowns, cross sensitivities can occur with 

compounds that have similar functional groups, i.e., the same principal bonds. In an 

effort to avoid this problem, the analyzer takes advantage of the fact that IR absorbance 

takes place at several, or even hundreds, of specific frequencies, depending on the 

compound and its interatomic bonds. For most of the compounds in the on-board 

library there are multiple frequencies from which to choose, so that if other compounds 
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present have absorption frequencies at or near those of the species of interest another 

frequency can be chosen. For Halotron I there are three frequencies to choose from. 

Some are not as sensitive as others, but all were tried in an effort to see if a cross 

sensitivity might be present. Unfortunately it does not appear that this answered the 

problem. Because of the high concentration spikes encountered earlier, the instrument 

was adjusted to a less sensitive setting in order to accurately measure Halotron I 

concentrations during this monitoring. Because of this, the limit of detection was 

between one and two orders of magnitude higher than previously, so that one cannot 

say with certainty if the lowest values are below the 3 ppm background identified before. 

This will be addressed during other work to be done at Amerex over the week of May 

21st, by monitoring in the vicinity of the other halon product. 

One other question dealt with the potential differences in levels of Halotron I when 

different size bottles were being filled, and if it might be significant. Monitoring 

conducted in March was almost all during the filling of the small bottles, and the average 

concentration was much lower, about 10 ppm vs 28 ppm for the large bottles in May. 

Several variables are in play. The small bottles fill considerably faster, so that the 

operator enters the booth and disconnects and connects the line more often. Therefore 

the time inside the booth is greater, and the potential for the fill line connection to leak is 

greater also. Alternately, the operator spends about twice as much time away from the 

fill booth area getting parts when filling the small bottles as the large ones. 

There is no immediate answer here, and it can only be found when the specific cause of 

the concentration spikes is identified. Robert Fisher, currently in Safety & Health at the 

facility but previously a worker at the fill booth, said that the rubber O rings at the bottle 

connection often lost their seal momentarily while he was filling them. On one occasion 

on May 2nd, at the end of the afternoon monitoring shown on the graph at about 1:35, 

the concentration on the analyzer was seen to exceed 250 ppm just one or two seconds 

prior to the end of the automated fill sequence. Perhaps the pressure at this point in the 

filling process is enough to occasionally overcome the capacity of the O rings. If so, this 

can be corrected through mechanical or electronic adjustment. 

Please feel free to contact DirectCIH if you have any questions regarding this work. 

Sincerely, 

Lindsay R. Hill, CIH 

Principal, DirectCIH LLC 
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