INVESTIGATION OF INDUSTRIAL USE OF HYDROFLUORIC ACID IN CALIFORNIA REGARDING LEGISLATIVE BILL AB 1759

THE INVESTIGATION OF INDUSTRIAL USE OF HYDROFLUORIC ACID IN CALIFORNIA

REGARDING LEGISLATIVE BILL AB 1759

JAMES BOOTH EVAN CHOY

HAIMING HU MANSU LIU

ERIKA POYNTER

Department of Mechanical and Aerospace Engineering, UC San Diego June 7, 2016

June 2016 Hydrofluoric Acid AB-1759

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EXECUTIVE SUMMARY

Background

In 2015, ExxonMobil’s Torrance refinery had two separate incidents involving hydrofluoric acid, sparking an ongoing

public debate regarding the petroleum industry’s use of the dangerous chemical while being close in proximity to residential

areas. In response to the events, California Bill AB-1759 was drafted and proposed to take effect immediately. Under section

25240.2(a), (b), the California Legislature declared that any business that, at any time, handles, maintains, or stores more

than 250 gallons of hydrogen fluoride, including hydrofluoric acid, shall, if possible convert to a known, substitute by

January 1, 2017. If it is not possible to convert to a known, significantly less hazardous substitute, and the business is located

within two miles of a residential dwelling, the business shall cease handling, maintaining or storing hydrogen fluoride and

hydrofluoric acid by January 1, 2017.

This report, developed in response to the California Bill AB-1759 and with the help of the Industrial Environmental

Association (IEA), is intended to identify the use hydrofluoric acid (also called HF) in different industries, the properties of

different concentrations of HF used, and potential hazards and risk to the public. The report is to determine whether AB-

1759 in its current form is justifiable or if changes ought to be made.

Summary of Findings and Recommendations

HF is a very toxic and corrosive inorganic acid. HF is used as the source of the fluorine molecule for the production of

fluorinated compounds. It is involved in the alkylation process to produce high octane fuel and is also used as an etching

agent in metalworking and etching industries. Furthermore, it is used to produce organofluorine compounds. HF is also

commonly used in common household products such as water spot removers, rust stain removers, and in ceramic and fabric

rust inhibitors. It is a fairly common compound that is used in varying concentrations for numerous processes.

An accidental release of industrial HF could have fatal consequences. HF is toxic to humans and can be extremely lethal as

documented by many workplace accidents. At 40% concentration and standard air pressure conditions, HF begins to fume.

At 70% concentration and standards conditions, it reaches its maximum saturation level and becomes highly volatile, fuming

heavily. Oil refineries use modified HF, which, under pressure, can reach even higher concentrations. At such high

concentrations, under certain conditions, and in large quantities, HF has the potential to form a dense vapor cloud that can

travel significant distances downwind posing a potential fatal threat to the public. It requires immediate and specialized

medical attention to treat HF exposure properly. As such, public safety is a significant concern for oil refineries which tend

to use high concentrations of HF and own facilities that are close to densely populated areas.

Bill AB-1759’s intent is to protect densely populated areas from the potential worse-case scenario of a HF vapor cloud

forming from an oil refinery. While this is undoubtedly a concern, the current legislature makes no mention of acceptable

hydrofluoric acid concentration/vapor pressure levels, a crucial omission. There are numerous companies that use low

enough concentrations (often 49% or lower) that formation of a dense HF vapor cloud does not seem possible.

Additionally, after reviewing multiple environmental agency’s reports such as the EPA, the U.S Chemical Safety Board,

CalARP, and OSHA, the conclusion was reached that the likelihood of an accidental release of HF can be kept low so long

as the facility managers and operators work responsibly by applying existing industry standards and practices, and adhering

to existing federal/state regulations.

Businesses that follow strict safety protocol and have protective measures that mitigate the spread/exposure of HF if

released. All facilities should be able to identify, mitigate, and quickly respond to accidental releases in order to minimize

the hazards. The U.S. Chemical Safety Board did not propose a ban on hydrofluoric acid in oil refineries, but believe that

the accidents that have happened in the past could have been avoided with a more analytical and structured approach that

could have helped to prevent or mitigate the effects of these accidents. The U.S. Chemical Safety Board recommended that

substantial changes need to be implemented to the way refineries are regulated in California. Chairperson Sutherland said,


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“The CSB is continuing to advocate for its process safety management recommendations and monitor

developments in California…the actions being taken in the state are some of the most substantive safety

improvements happening the United States right now.”[25]

Our first recommendation, which is less drastic than this bill, is to more stringently enforce the current federal and state

laws regarding HF. As discussed earlier, there is already an extensive network of standards and regulations for facilities

using HF. The current regulations, when properly followed, tremendously reduce the likelihood of an accident, as seen with

companies like UTC Aerospace and Air Products & Chemicals, which have not even had a minor HF accident affecting the

public. On the other hand, the Torrance refinery incident arose because current standards and regulations were not being

adhered to by management. We propose that to ensure these regulations are followed, the penalty fines associated with

violations be substantially increased. These fines can then be used to offset the costs of the additional and stricter inspections

incurred in this process

We strongly recommend that the bill recognize the difference in threat level that HF poses at difference concentrations, as

is done with other chemicals such as hydrochloric acid. The hazard posed by a 30% concentration HF solution cannot

reasonably be compared to a 70% concentration HF solution. As such, we propose that the bill follow federal guideline

practices and focus on facilities that handle HF concentrations over 50% such as oil refineries. Furthermore, due to its effect

on fuming, the bill should seriously consider the establishment of a vapor pressure threshold. Many companies in California,

such as Air Products and Chemicals and UTC Aerospace, responsibly use HF at concentrations less than 50% at standard

air pressures, and their working conditions present minimal public safety threat. To force these companies to halt the use of

HF would be catastrophic to California’s economy, yet would not provide the public safety benefit that the bill seeks.

If our other proposals are not to be followed, our final proposal (and as a last resort) is that the bill should extend the time

period before it goes into effect as to allow for additional time if it is going to force oil refineries to find a safer alternative

to use in the alkylation process.

The United Steel Workers Study has concluded that there are a few alternatives to HF. The first, which replaces HF with

sulfuric acid alkylation has already been implemented in some refineries, though it has its drawbacks. As discussed in

section 4.5, sulfuric acid is much safer than HF but it still poses serious hazards for workers, the public and the environment,

and is not for certain an effective alternative. Secondly is solid-acid catalyst alkylation which has been studied and

implemented by a few companies. Another is ionic-liquid alkylation, a process that has been successfully developed and

implemented in Chinese refineries and is in the pilot and production phase. The two processes are much safer for workers

and the public because of it does not use HF or sulfuric acid. However, more research and studies must be conducted in

order to determine if either are a reliable alternative and are able to meet California’s unique gasoline blend regulation. With

all factors considered, there is absolutely no way an alternative will be available by 2017. Furthermore, any alternative will

come at enormous costs, costs which could be enough to force the shutdown of refineries.


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Table of Contents

1. Introduction …………………………………………………………………………………………………………………………………………………………………6

1.1 Project Definition .......................................................................................................................................................... 6

1.2 California Bill AB-1759 ................................................................................................................................................... 6

1.3 Objective ....................................................................................................................................................................... 6

2. Background of Hydrofluoric Acid…………………………………………………………………………………………………………………………………..6

2.1 Chemical Properties ...................................................................................................................................................... 6

2.2 Risks to Human Health .................................................................................................................................................. 7

2.3 Hydrofluoric Acid use in Industries ............................................................................................................................... 7

2.3.1 Oil Refineries .......................................................................................................................................................... 7

2.3.2 Etching and Microfabrication ................................................................................................................................. 8

2.3.3 Organo-fluorine Compound Production ................................................................................................................ 8

3. Methods and Procedure……………………………………………………………………………………………………………………………………………….8

4. 2015 ExxonMobil Incidents propagated AB-1759………………………………………………………………………………………………………….8

4.1 Torrance Refinery Explosion ......................................................................................................................................... 9

4.1.1 Torrance Refinery Explosion Investigation ............................................................................................................ 9

4.1.2 Management of Change Review .......................................................................................................................... 10

4.2 Response to the February Explosion ........................................................................................................................... 10

4.3 Hydrofluoric Acid Leak at the Torrance Refinery ........................................................................................................ 10

4.4 Response to the Hydrofluoric Acid Leak ..................................................................................................................... 11

4.5 ExxonMobil Torrance Refinery Aftermath .................................................................................................................. 12

5. Industry Analysis…………………………………………………………………………………………………………………………………………………………13

5.1 Standard Handling and Emergency Procedures.......................................................................................................... 13

5.2 Air and Chemical Products .......................................................................................................................................... 13

5.2.1 Concentration/Amount stored and used ............................................................................................................. 14

5.2.2 Safety Procedure .................................................................................................................................................. 14

5.2.3 Bill’s Effect on Industry ........................................................................................................................................ 14

5.3 UTC Aerospace Systems .............................................................................................................................................. 14

5.3.1 Concentration/Amount stored and used ............................................................................................................. 14

5.3.2 Safety Procedure .................................................................................................................................................. 15

5.3.3 Bill’s Effect on Industry ........................................................................................................................................ 15

6. Strong Regulatory System in Place………………………………………………………………………………………………………………………………15

6.1 Environmental Protection Agency ............................................................................................................................. 15


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6.2 Federal Risk Management Plan................................................................................................................................... 15

6.2.1 Risk Management Plans ....................................................................................................................................... 16

6.2.2 General Duty Clause ............................................................................................................................................. 16

6.2.3 FRMP Programs .................................................................................................................................................... 16

6.3 California Accidental Release Prevention (CalARP) .................................................................................................... 17

6.3.1 Hazards Assessment & Five-year Accident History .............................................................................................. 17

6.3.2 Training, Maintenance, & Compliance Audits ..................................................................................................... 17

6.3.3 Contractors........................................................................................................................................................... 17

6.4 Occupational Safety and Health Administration ........................................................................................................ 17

7. Relationship to Hydrochloric Acid……………………………………………………………………………………………………………………………….18

8. Findings and Recommendations………………………………………………………………………………………………………………………………….18

8. References………………………………………………………………………………………………………………………………………………………………….19

9. Appendix…………………………………………………………………………………………………………………………………………………………………….23


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1. Introduction

1.1 Project Definition

Hydrofluoric acid (HF) is a highly dangerous and volatile chemical which, in high concentrations (approximately 70%), has

the capacity to cause great harm to the public. However, HF is used in numerous industries throughout California and for a

variety of functions. Legislation AB-1759 was proposed to restrict the industrial use of hydrofluoric acid and would greatly

affect the industries in California which use the chemical. The Industrial Environmental Association (IEA), an association

that promotes responsible and economically-wise environmental laws, along with a coalition of companies, were able to put

a hold on the bill before it was able to go into effect. This project calls for a synthesis of facts to create an informative report

to provide to legislators, enabling them to make a collective and informed decision regarding this bill.

1.2 California Bill AB-1759

The entirety of this study is based on the California bill AB 1759 that was introduced on February 2, 2016 by assemblyperson

Rob Bonta. The bill contains two main parts pertaining to the regulation of hydrofluoric acid. The first part calls for all oil

refineries which use hydrofluoric acid to notify the public living within a three-and-a-half-mile radius of the plant’s use of

the chemical. Furthermore, residents living within a two-mile radius shall be warned that they live in the lethal zone (Section

39668.5 (a) & 1.A), which is defined as the area in which individuals will be exposed to life-threatening health effects after

an hour of contact with the toxin, if a release were to occur. (Section 39668.5 (2.C)). The second part calls for all businesses

that handle and store over 250 gallons of hydrofluoric acid on site, and are located within a two-mile radius of residential

dwellings, to either switch to a less hazardous alternative, and if a less hazardous alternative does not exist, cease using HF

altogether by January 1, 2017 (Section 25240.2.a). It is noted that there is no mention of hydrofluoric acid concentration. It

is clear that the priority of the bill is public safety rather than refinery worker safety. The primary fear of a HF vapor cloud

harming nearby residents is apparent in the bill: it states that at any moment 500,000 of the 616,000 Californian residents

living within 3.5 miles of a refinery can be killed due to the presence and potential uncontrolled release of 60,000 lbs. of

modified hydrofluoric acid. According to the bill, an HF vapor cloud can be lethal up to 5 miles downwind.

1.3 Objective

This bill is attempting to stop oil refineries from storing and handling large amounts of modified hydrofluoric acid, but a

blanket ban on hydrofluoric acid will not only affect refineries but also other industries that use relatively safe concentrations

of HF. It could lead to the unintended outcome of entire industries leaving California for states with more lenient regulations,

and thereby causing job losses and a decline in California’s economy.

The objective of this project is to provide an unbiased report to assemblyperson Rob Bonta regarding the bill, which details

the health, economic, and safety impacts of the use of HF. This report will provide a complete picture of the effects of HF

regarding the interests of the state of California and will ensure an informed decision can be made. Lastly, our report will

provide our own recommendations to improve the bill.

2. Background of Hydrofluoric Acid

2.1 Chemical Properties [16], [17] Hydrofluoric Acid (HF) is an industrial chemical and is available in both an aqueous and anhydrous form. Aqueous

hydrofluoric acid is a colorless liquid that is produced by dissolving HF in water, thus creating HF solutions at various

concentrations. Under standard conditions, such as those found in university laboratories, aqueous HF will begin to fume at

concentrations around 40%. Relatively dilute HF with concentrations of less than 40% do not produce significant vapor

concentrations unless superheated and placed under large amounts of pressure, conditions that might typically be found in

oil refineries. HF reaches its maximum saturation at 70% (under standard conditions), at which point it is at its most volatile

state and will fume profusely. Anhydrous HF has a much lower boiling temperature than aqueous HF, and thus anhydrous

HF will begin to fume at temperatures close to room temperature, making it much more dangerous than its aqueous

counterpart.


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In both its aqueous and anhydrous forms, HF can cause pressure buildup which can rupture containers when reacted with

glass, concrete and other silicon bearing materials. A reaction with carbonates, sulfides and cyanides will yield toxic gases.

It is corrosive to many materials including leather, natural rubber and other organic materials.

Specific chemical properties for 70% aqueous concentration HF can be found in Figure 1 in the Appendix. Unless otherwise

specified, any mention of hydrofluoric acid in this report assumes aqueous HF.

2.2 Risks to Human Health [16], [17], [18] Like other acids, hydrofluoric acid burns skin at varying degrees depending on the concentration. Unsurprisingly,

a higher concentration solution of HF will lead to more aggressive burns and an increase in health complications. The initial

signs of chemical burns are redness at the burn location, blistering, and edema, swelling in the tissues due to accumulation

of extra fluid. Additionally, a high level concentration of HF will blanch the skin at the burn site. A solution concentration

of 0%-49% can delay symptoms for as much as 1-8 hours, which results in a delay in the appearance of need for medical

intervention. During this time however, the HF will begin to cause damage to the skin and underlying tissue. At a

concentration below 19%, symptoms can take as long as 24 hours after exposure to manifest, delaying the apparent need

for medical intervention even longer. Delayed medical treatment allows HF time to seep into the deep tissue and enter the

blood stream causing more severe health complications. A concentration of more than 50% will lead to an immediate and

apparent burn after skin contact, and requires immediate medical intervention.

The fluoride component of HF makes this acid exceptionally more dangerous than other acids. During initial contact, the

fluoride ion enables the HF to penetrate the skin very readily, and it generally takes the body longer to neutralize HF than

other acids. Once HF has entered the body, a throbbing sensation occurs due to the fluoride ion bonding with the calcium

ions in the bloodstream, bones, and other parts of the body. The body compensates by releasing potassium which irritates

nerve ending and thus causes the throbbing sensation. In rare cases, the attraction of fluoride and calcium ions leads to

decalcifying of the bones. If left untreated, skin contact of HF can lead to permanent damage, disability, and even death.

The gas phase of HF is extremely corrosive and can be fatal if inhaled. Chemical burns can occur in at all points of contact

including the eyes, skin and mucous membranes such as the throat, nasal cavity and lungs. Even at low concentrations, the

HF fumes are dangerous if inhaled.

2.3 Hydrofluoric Acid use in Industries

Hydrofluoric acid is used in a variety of industries. For example, it is handled in oil refineries, the metalworking and etching

industry, and in organofluorine chemistry. Very low concentrations of HF are also in household products such as rust stain

remover, water spot removers and in ceramic and fabric rust inhibitors. It is a fairly common compound that is used in

varying concentrations for a number of useful processes.

2.3.1 Oil Refineries [4] In oil refineries, hydrofluoric acid is used as a catalyst for the alkylation process with other low-molecular-weight alkenes

to produce high octane rating C7-C8 compounds. High octane rating products are used as a premium gasoline additive to

prevent pre-ignition and knocking in car engines. High octane fuel is necessary for high performance gasoline engines such

as jet fuel for aircrafts.

[5] Since the protonation of alkenes is the initial critical step in the alkylation reaction, a very strong acidic environment,

usually 83% to 90%, is needed. At low acid concentrations, side reactions such as organic fluorine formation occur, and

acid runaway in which all the acid is consumed in side reactions, can occur. As an alternative to HF, sulfuric acid also

provides good catalytic performance, but this process produces lower octane rating products and has a higher acid

consumption rate and thus requires more sulfuric acid than hydrofluoric acid.

[31] In California there are currently two refineries that use modified hydrofluoric acid (MHF), ExxonMobil’s Torrance

refinery and Valero’s Wilmington refinery. MHF is highly concentrated hydrofluoric acid (70% - 90%) that is modified

with an additive which reduces the acid’s vapor pressure and lowers the probability of forming a dense vapor cloud.


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However, excess additive will damage the production of high octane fuel and the effectiveness of the additive’s ability to

reduce HF’s vapor pressure is uncertain.

2.3.2 Etching and Microfabrication [6],[23],[30] In the microelectronics industry, HF-based solutions are used extensively for wet etching of SiO2 or Si3N4, a

chemical process which is used to fabricate integrated circuit wafers and micro machines. Due to the unique structure of

silicon dioxide (SiO2), hydrofluoric acid is the only chemical that reacts with SiO2 at a high rate at room temperature. This

property of HF was first used to process, dissolve and clean silicate glasses. Diluted HF solutions and enhanced HCl/HF

solutions are also used for related, special applications.

Besides etching glasses and micro machines, hydrofluoric acid, due to its moderate reactivity towards many metals, is used

to etch transition metals, commonly aluminum, titanium, and their alloys. The etching process is very similar to that of

silicon dioxide, with additive chemicals such as nitric acid to eliminate generation of hydrogen gas and control reaction rate.

The final buffered HF solution is 3% to 10% concentration of HF.

2.3.3 Organo-fluorine Compound Production [23],[29],[36] Organo-fluorine compounds have many applications in the pharmaceutical industry. The synthesis of organo-

fluorine compounds involves the process of fluorination, a process in which fluorine is introduction into organic compounds

by forming carbon-fluorine (C-F) bonds. The C-F bond is the strongest single bond in organic chemistry and high desirable

in this application. Direct fluorination using gaseous fluorine is a difficult and expensive route. On the other hand, hydrogen

fluoride is an inexpensive and readily available commercial product, and its compound form of fluorine ion makes it an

attractive fluorinating agent.

The two widely used fluorination methods are electrochemical oxidative fluorination and halogen exchange fluorination. In

electrochemical fluorination, a HF containing solution is electrolyzed at about 5V near 0 °C producing the fluorinated

organic compound. Halogen exchange, as its name suggests, is the substitution of fluorine into other halogens in the existing

carbon-halogen bonds, thus producing carbon-fluorine bonded compounds. This process is industrially important in the

manufacture of refrigerants such as Freon. HF is the source for many other organofluorine compounds such as Teflon,

fluorocarbons, and fluoropolymers.

3. Methods and Procedure

The first step of this report was to perform independent research on the different aspects of the bill, the chemical properties

of HF, the ExxonMobil incidents, standard handling procedures of HF, current regulations regarding HF, and other

chemicals similar to HF. A wide variety of sources were used when conducting this research, such as the EPA and historic,

industrial reports and studies on HF.

Meanwhile, contact was established with some companies in the San Diego area that use HF through the assistance of Jack

Monger of the IEA. Specifically, Randy Skow of the Environmental Health & Safety Department (EH&S) at Air Products

and Chemicals (Carlsbad, CA), and Rick Siordia and Paul Johnson of the EH&S Department at UTC Aerospace Systems

(Chula Vista, CA) were contacted. Site visits with these companies were scheduled and conducted, and the findings of these

visits are discussed later in this report.

4. 2015 ExxonMobil Incidents propagated AB-1759

Since 1979, the Torrance refinery has been involved in over 80 incidents involving HF and it has had 22 incidents involving

hydrofluoric acid since 2010. (Section 1.d) The most recent events at the refinery were in Feb. 2015 and Sept. 2015. The

Feb.2015 incident was an explosion that nearly missed hitting a tank containing thousands of lbs. of high concentrated

(>70%) hydrofluoric acid. It was categorized as a serious near-miss and would have been catastrophic to the surrounding

communities if a hydrofluoric vapor cloud had formed. The Sept. 2015 incident involved a faulty equipment piece that


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contributed to the slow leak of modified hydrofluoric acid while the containment tank was under a refill operation.

ExxonMobil at the time owned the Torrance refinery (it was sold to independent refiner PBF Energy on Sept. 30, 2015).

4.1 Torrance Refinery Explosion [29], [35] On February 2, 2016, California’s Assembly Bill AB 1759 was drafted and proposed in response to the recent events

that took place at ExxonMobil’s Torrance refinery last year. On February 18, 2015, an explosion at the refinery caused a

piece of equipment weighing approximately 80,000 pounds to be sent flying over 100 feet and landing a few feet away from

a tank containing hydrofluoric acid. If released, the hydrofluoric acid could have formed a vapor cloud of toxic gas that

could travel for miles, possibly injuring or killing the more than 200,000 residents that live within a three-mile radius from

the facility. The blast injured four workers and was categorized as a serious near miss that could have been fatal to nearby

communities. The blast was so strong, it registered a 1.7 on the Richter scale. The U.S. Chemical Safety Board said that

there are 333,000 residents, 71 schools, and eight hospitals within a three-mile radius from the refinery. The blast dispersed

large quantities of catalyst dust up to a mile away from the facility. Vanessa Allen Sutherland, chairperson of the Chemical

Safety Board said

“After hydrofluoric acid vaporizes, it condenses into small droplets that from a dense low-lying cloud

that will travel for several miles and cause severe damage to respiratory system, skin, and bones, potentially

resulting in death.” [29]

The events leading up to the explosion began on February 12, 2015 when workers noticed problems with the expander, a

part of the fluid catalytic cracking unit (FCCU), and set the FCCU in idle condition. With the FCCU shut down, steam was

forced into the reactor to prevent hydrocarbons from flowing back into the main distillation column. On the morning of

February 18, 2015, steam was escaping through an open flange on the expander, which prevented operators from continuing

maintenance work. The steam traveled through a leaking slide valve connected to the reactor. An outside supervisor reduced

the amount of steam flowing into the reactor so that work could continue, however, the workers were unaware that

hydrocarbons were leaking into the main distillation column from interconnected equipment. The hydrocarbons escaped

through the open valve and into the refinery’s electrostatic precipitator (ESP), accumulating inside the ESP igniting the

hydrocarbons and causing the explosion.

4.1.1 Torrance Refinery Explosion Investigation [3], [29] The U.S. Chemical Safety Board (CSB) is an independent federal agency responsible for investigating serious

chemical accidents. The agency does not issue citations or fines but focuses on making safety recommendations to

companies, industry organizations, labor groups, and regulatory agencies such as Occupational Safety and Health

Administration (OSHA) and the U.S. Environmental Protection Agency (EPA). The board members are appointed by the

President and confirmed by the Senate. The CSB’s investigations analyze all aspects of the chemical accident, including

physical causes such as equipment failure as well as inadequacies in regulations, industry standards, and safety management

systems.

Following the February 18, 2015 accident, the CSB had conducted an ongoing investigation regarding the series of events

that led to the explosion and found several safety management deficiencies that led to the accident. The CSB found that one

of the pieces of debris hit scaffolding in the refinery’s alkylation unit and was close to hitting a tank filled with tens of

thousands of pounds of HF. CSB investigators discovered that ExxonMobil prematurely granted permission for the FCCU

to be operational by neglecting several existing procedures. ExxonMobil bypassed the existing procedures by using a

document called a variance, a written temporary deviation from normal operating procedures. However, the variance used

was created in 2012 to address problems with the expander and CSB investigators found that ExxonMobil had not conducted

a management of change review before implementing the outdated variance even though conditions for the FCCU had


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changed over the previous three years. Exxon Mobil also performed inadequate process hazard analyses that could have

identified more effective safeguards against the flow of hydrocarbons, such as blind or de-inventorying the main distillation

column. Investigator-in-charge, Mark Wingard said,

“Although our investigation found two different process hazard analyses that considered a combustible

mixture igniting in the electrostatic precipitator, no effective safeguards were implemented at the refinery to

mitigate this threat.” [21]

If ExxonMobil had executed proper procedure the accident would likely have not occurred. ExxonMobil claims that the

accident had no potential risk to the surrounding community members.

4.1.2 Management of Change Review [3], [29] A Management of Change review is a practice used to establish that safety, health, and environmental risks are

contained when a company makes changes in their facilities, documentation, personnel, or operations. In August 2001, the

CSB released a safety bulletin on management of change and its useful and beneficial practice to ensure that safety, health,

and environmental risks are controlled. The failure to conduct a Management of Change review or perform hazard analysis

is similar to other CSB refinery investigations, including the fire at the Chevron Refinery in Richmond, California on August

6, 2012. The Chevron incident was more serious in that the fire endangered 19 workers and sent more than 15,000 residents

to the hospital for medical attention. The conclusion of their Chevron investigation, the CSB recommended that substantial

changes need to be implemented to the way refineries are regulated in California. Chairperson Sutherland said,

“The CSB is continuing to advocate for its process safety management recommendations and monitor

developments in California…the actions being taken in the state are some of the most substantive safety

improvements happening the United States right now.”[25]

4.2 Response to the February Explosion [1] On Aug. 13, 2015, Cal/OSHA cited ExxonMobil for 19 alleged violations, totaling $566,600, after an investigation into

the Feb. 18, 2015 explosion at the Torrance facility. The investigators concluded that the management failed to take action

and were aware of the hazardous conditions at the fluid catalytic cracker unit, the unit that had exploded. The investigators

said that as far back as 2007, the Torrance refinery had identified flammable vapor leakage into the precipitator, but “failed

to correct the danger”. A half-dozen of the violations were categorized as serious-willful because ExxonMobil intentionally

failed to comply with state safety standards. Each serious-willful violation came with a proposed $70,000 penalty.

Cal/OSHA also cited ExxonMobil for 12 serious violations, ranging from $7,200 to $21,600 each.

4.3 Hydrofluoric Acid Leak at the Torrance Refinery [9], [12] On September 6, 2015 at 2:35 a.m., a leak of modified hydrofluoric acid was discovered at a rate of 10 drops per

minute, unrelated to the explosion in February. The leak occurred from a 3-inch nozzle during a routine transfer as a truck

unloaded HF into a containment vessel at the facility. The temperature and surrounding conditions of the leak would not

have caused the HF to form a dense vapor cloud. Torrance Assistant Fire Chief Martin Serna said that the leak was fixed by

6 p.m. Sunday, meaning that the leak occurred for over 16 hours. Firefighters handled the situation safely by depressurizing

the vessel and neutralizing the spill with water. The Torrance Fire Department said that the safety action resulted in a reading

of zero parts per million of HF acid 2 feet from the leaking vessel. ExxonMobil’s spokeswoman Gesuina Paras said,


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“The amount of material leaked was significantly below quantities required to be reported to

regulatory agencies. However as a matter of practice, ExxonMobil notified the Torrance Fire Department

and South Coast Air Quality Management District…there was no impact to people, the environment or the

community.” [9]

Despite the ExxonMobil’s reassurance, Jim Tarr, president of Rolling Hills Estates-based Stone Lions Environmental

Corporation, with almost four decades of experience evaluating toxic chemical and air pollution exposure said that this

should be a wake-up call.

“The use of modified hydrofluoric acid at the ExxonMobil refinery needs to be discontinued as soon

as possible…everyone needs to understand these hydrofluoric acid releases can occur without notice and the

next one may be much more substantial than this one.” [12]

4.4 Response to the Hydrofluoric Acid Leak [2], [12] The Torrance Fire Department disclosed that ExxonMobil failed to follow the established safety procedures to notify

the Fire Department of the Sept. 6, 2015 hydrofluoric acid leak. In a Sept. 10 letter to refinery manager Brian Ablett, Deputy

Fire Chief David Dumais wrote,

“It appears to the Torrance Fire Department that the on-duty safety advisor did not follow the

Reporting Protocol Flowchart – Leak/Spill/Release section as established and agreed upon by Torrance Fire

Department and ExxonMobil Torrance Management. Since the site safety advisor found an active modified

hydrofluoric acid (MHF) leak and the MHF alarms had been activated, the site safety advisor should have

notified fire dispatch for a hazardous materials response.” [12]

The Torrance Fire Department reported that the on-site safety advisor sent an email notifying the Fire Department of the

leak approximately 30 minutes after the leak had been detected. Approximately six hours later, 8:38 a.m., the on-site safety

advisor made a phone call to the on-duty platoon commander to notify him of the MHF spill. The Torrance Fire Department

requested that ExxonMobil establish an “action plan” to improve the protocol of reporting incidents at the facility for the

well-being of the community.

On March 4, 2016, Cal/OSHA issued three citations totaling $72,120 to ExxonMobil Refining & Supply Company for

failure to repair faulty equipment at its Torrance refinery for four years. This was found after the state agency’s investigation

following the HF leak at the refinery’s alkylation unit on Sept. 5, 2015. Investigators discovered the leak was due to a

temporary clamp that was installed on a 3-inch nozzle flange that was also related to an earlier leak in 2011. Cal/OSHA

Chief Juliann Sum said,

“This is a case [where] a minor repair could have prevented workers at this refinery from exposure

to a life-threatening acid…these citations and penalties are a wake-up call that refineries must follow strict

safety protocols to protect their employees.” [2]


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Cal/OSHA said that the three citations included one willful-serious, where the employer was aware of the hazardous

condition and did not take reasonable steps to address it. The other two general citations were for ExxonMobil’s alleged

failure to conduct a hazard analysis and identify and fix the 2011 leak. Cal/OSHA’s news release said

“ExxonMobil mitigated the leak caused by the faulty clamp within 48 hours of the release. The

company also removed tank 5C-31 from service, where the faulty nozzle was attached, to make repairs. Before

ExxonMobil was allowed to restart operations in January, a complete inspection of the alkylation unit was

conducted to ensure there were no additional leaking flanges or nozzles.” [2]

4.5 ExxonMobil Torrance Refinery Aftermath [11] The recent events at the Torrance refinery has had several impacts on California. The most important is that it has re-

opened a discussion for an outright ban on the use of hydrofluoric acid. Led by the grass-roots Torrance Refinery Action

Alliance, Torrance residents and communities in the South Bay are concerned that they are living in a life-threatening area,

an area where a worst-case scenario at the Torrance refinery could be fatal to the over 250,000 surrounding residents.

Since the explosion and at the time of this report’s writing, the Torrance refinery had been operating at 20% capacity which

has had an impact on California’s gas prices. At 100% operations, the refinery is responsible for supplying the state with

10% of its gasoline supply and more specifically 20% of Southern California’s refined gasoline supply. Gasoline prices are

expected to decrease after the South Coast Air Quality Management District (SCAQMD) ruled to allow ExxonMobil to

restore the Torrance refinery to full operations. In fall 2015, ExxonMobil sold the refinery to independent oil refiner, PBF

Energy, who will be taking over the facility once ExxonMobil restores the facility to fully operational.

Because of ExxonMobil’s numerous incidents with HF, the Torrance Refinery Action Alliance, government representatives,

and community members have petitioned for an outright ban on Torrance and Wilmington’s facility use of HF. HF is not

only dangerous in the production process but is also considered by the FBI to be a potential chemical weapon for terrorists

to utilize. Large tanks are transferred by trucks across highways and streets to these facilities, often without any security

guarding their pathways.

[9], [31] PBF Energy has had an excellent track record handling HF, with zero incidents in the last 5 years during their

operations. A ban on the use of HF will force the Torrance refinery and Wilmington refinery to either shut-down or switch

to sulfuric acid. The switch to sulfuric acid is a very expensive process as multiple equipment will have to be replaced, a

process that will cost approximately $100 million dollars according to a 1988 report. This process would also use 100 times

more sulfuric acid than HF. It is not known whether the sulfuric acid substitute produces the same octane content and refined

gasoline that made the modified HF so desirable. Because of state regulations, California’s gasoline supply is a unique blend

that is less harmful for the environment. If the Torrance refinery refuses to convert to sulfuric acid and shuts-down,

California will lose 10% of its refined gasoline supply plus the amount produced from the Wilmington refinery, possibly

resulting in even higher gas prices. Furthermore, sulfuric acid is a dangerous chemical as well and using 100 times more

acid needs to be considered if a switch is made.

[11], [29] The risk from human error is prevalent in all industries, but is magnified when dealing with volatile combustible

reactions and life-threatening acids such as HF. The CSB did not propose a ban on hydrofluoric acid in oil refineries, but

believe that the accidents that have happened in the past could have been avoided with a more analytical and structured

approach that could have helped to prevent or mitigate the effects of these accidents.


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5. Industry Analysis

5.1 Standard Handling and Emergency Procedures

Both anhydrous and aqueous solutions of hydrofluoric acid require immediate and specialized medical treatment, and as

such all facilities working with hydrofluoric acid must have a rigorous set of safety measures to minimize the chance of

injury, and to reduce damage once exposure has occurred. The following safety measures are professional-recommended

and should already be in practice for any facility meeting current legal mandates, such as the Federal Risk Management

Plan, discussed in Section 6. With that being said, such mandates only provide a minimum safety benchmark for any facility

working with HF, and many facilities require much stricter and more in-depth protocols.

[17] Any facility, whether it be for industrial or academic purposes, must establish a Standard Operating Procedure (SOP)

specifically for hydrofluoric acid. All facilities which have met state requirements to use HF on-site should already have

one of these. Additionally, HF should only be used in specific and designated areas, which have essentials such as the SOP,

HF MSDS, and a first-aid and spill kit, which contains equipment that shall be discussed later in this section. [13] Any individual working with HF must undergo sufficient safety training. The training should include a description of

the medical hazards of HF, how to recognize exposure symptoms, and initial first aid measures to take, along with a

demonstration of such. Additionally, it should include a demonstration on how to properly put on adequate personal

protective equipment (PPE), as well as cleaning and decontamination procedures. Adequate PPE varies immensely

depending on the amount, form, and concentration of HF being used. In a small laboratory setting with no vapor release, it

entails splash-proof goggles and a plastic face shield, and no contact lens if possible. Double-gloving is recommended, and

neoprene or Polyvinyl chloride [PVC] gloves should be worn over nitrile gloves, and replaced at first sign of

contamination. Additionally, and acid-resistant apron should be worn and all other skin covered. If fuming is a concern,

and above 40% concentration it is, proper respirators are necessary, and OSHA lists the permissible exposure limit as 3

ppm. Lastly, eyewash stations and showers must be immediately accessible. Sufficient safety precautions such as the ones

listed above are required by law, such as California Accidental Release Prevention (CalARP), discussed in Section 6.

[27] The speed at which exposure to hydrofluoric acid can be detected depends upon the strength of the solution. Exposure

to a solution with concentration above 50% will cause immediate and sharp pain. Between 20 to 50% concentration, pain

may not occur for one to eight hours, and below 20% concentration, symptoms may take as long as 24 hours to manifest.

These time estimations are applicable for skin, dermal, and respiratory exposure. Though the exact procedure to treat exposure depends on the route, many of the steps that ought to be taken are applicable

for multiple routes, and skin exposure will primarily be discussed in this report. However, any facility using HF must have

explicit instructions for medical treatment for skin, eye, oral, respiratory, and nail exposure. [27] The first step once exposure occurs is to immediately flush the area with water with using either a hand washing station

or a safety shower and remove all clothing. Calcium gluconate 2.5% gel should be applied to the afflicted areas, and can be

massaged into the skin while flushing with water. Be liberal with the gel and reapply every 15 minutes, and continue to do

so while medical personnel are contacted. Despite the severe pain of HF burns, it is critical that no pain-reducing drugs are

given, as relief of pain is the primary indicator of success of treatment. For deeper burns, injection of 2.5% aqueous calcium

gluconate with a needle may be necessary. Do not use more than 0.5cc per square centimeter initially, and leave this

procedure to a physician only. For very severe burns (covering more than four square inches), the individual ought to be

transported immediately to an ICU. Any medical personnel must use minimum PPE as well (such as gloves) to prevent the

spread of hand burns. If severe exposure occurs, medical personnel must also be aware of hypocalcemia.

5.2 Air and Chemical Products

The Air Products & Chemicals facility in Carlsbad, CA, is responsible for the manufacture of various high purity chemicals

which are crucial in the manufacture of semiconductors. Hydrofluoric acid is used because it is exceptionally good at

cleaning quartz, one of the primary components of the containers used to ship the chemicals. The chemicals are of an ultra-


Page 14

high quality, and thus must be shipped in ultra-clean containers, and HF is the only chemical which has been able to provide

a satisfactory level of cleaning. While the company has done minimal research into alternative chemicals, the semiconductor

industry is notorious for being highly resistant to change. A change in procedure (such as using a different cleaning

chemical) would be met with disapproval from their customers, and a significant loss of business would be expected.

5.2.1 Concentration/Amount stored and used

Air Products initially purchases reagent-quality HF in 1 gallon containers, in its aqueous form at 49% concentration. Air

Products does not use anhydrous HF. Only 12 gallons are stored on-site at a time, which are stored in a standard corrosive-

resistant cabinet contained in another secondary container. This HF is then used in a mixing process, which dilutes it down

to either a 5% or 10% batch concentration, depending on which cleaning station it will be used at. The machines at these

stations are also secondarily contained and the cleaning process for the primary station is automated, minimizing contact

with HF. Once the batch is made, it is monitored on-site until the quality deteriorates sufficiently that it needs to be replaced.

5.2.2 Safety Procedure

Air Products has an extensive list of safety protocols for managing HF. An eye washing station and a shower are seconds

away from the cleaning machines, as are spill and first aid kits. Proper PPE included goggles, protective shield, and apron,

and the floor is corrosive-resistant. In case of emergency, the company Emergency Action Plan calls for the room to be

immediately isolated and automatically contacts the fire station, which has recorded arrival times of less than 5 minutes

from training exercises. Additionally, there are 16 trained emergency responders on-site.

There are several administrative procedures in place in order to prevent an accident from occurring in the first place. The

laboratory undergoes monthly inspections, and each piece of equipment has its own preventive maintenance plan. Air

Products also undergoes an in-company audit every 3-5 years which mimic state and federal inspections. They follow state

regulations regarding the discard of the HF batch.

5.2.3 Bill’s Effect on Industry

According to Mr. Skow, AB-1759 would not have a large impact on the manufacturing process as there is usually less than

250 gallons stored on-site. However, it could affect the site under certain conditions. Specifically, after a batch is replaced

but before the old batch is discarded, the 250-gallon threshold may be broken. However, the HF stored is all aqueous and

low in concentration, thus the release of a large vapor cloud is not possible. Mr. Skow mentioned that a major fault in AB-

1759 was that there was no specific mention of concentration levels for the HF ban. He felt that this was an important

oversight because there is a considerable difference between high and low concentrations of HF.

5.3 UTC Aerospace Systems

UTC Aerospace Systems manufactures aerospace and defense products. One of the key goals in aerospace product

manufacturing is to reduce weight of the components. To achieve this, UTC Aerospace Systems uses hydrofluoric acid to

etch metals to reduce mass while maintaining structural and mechanical integrity. Currently no machinery is capable of

producing the same results and is as effective and efficient as chemical etching.

5.3.1 Concentration/Amount stored and used

HF is never stored or produced in massive quantities on site. Approximately 500 lbs. of ammonium bifluoride, a salt form

of fluoride, is stored on site instead. Nitric acid is added and reacts with the salt to produce HF at a concentration of less

than 20%, far below the vapor generating concentration around 40%. Raw chemicals at UTC Aerospace Systems, including

ammonium bifluoride, are based on an order-delivery schedule within a few days. Any shipment of new chemicals must go

through an extensive review and purchase procedures by scientists and company managers. Upon delivery, each shipment

is tagged with a unique label so that they can keep track of how the chemical is used and the quantity used.


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5.3.2 Safety Procedure

The HF-producing reactions take place in air-exposed tanks which are housed in a large warehouse with a controlled air

flow. Operators work 3 ft. away from the tanks, and fans blow tank fumes away from the operators to avoid any inhalation

of chemical vapors. These fumes (if any) are removed from the warehouse by the air flow, which then undergo treatment

by a scrubber to clean the air before it is released. The chemical levels of the air are rigorously monitored to ensure they are

below all state and federal regulations before leaving the facility. Tank reactors are placed in secondary containment, to

guarantee any spills or overflow will be diverted back to the tanks by gutters. In case of emergencies, eyewash and shower

stations are in close proximity, and are able to be reached within 10 seconds, complying with government regulation.

Emergency alarms are installed on site, and an emergency response team is prepared to handle any spills.

5.3.3 Bill’s Effect on Industry

According to Mr. Siordia and Mr. Johnson, Bill AB-1759 will have minimal effect on their company's manufacturing and

handling procedures since hydrofluoric acid is an intermediate in the production process and is never stored or produced

in large quantities. Processes that require large amount of hydrofluoric acid have been relocated out of California.

However, Mr. Siordia and Mr. Johnson, along with Mr. Skow from Air Products and Chemicals, all noted that the lack of

specification on concentration or vapor pressure of hydrofluoric acid is problematic because properties of HF differ

largely depending on concentration. Mr. Johnson also suggested that there have are numerous and sufficient safety

regulations and requirements already in place regarding the usage of hydrofluoric acid, and the right path is to more

effectively enforce these regulations rather than creating more.

6. Strong Regulatory System in Place

Hydrofluoric acid, along with numerous other dangerous chemicals, are heavily regulated by multiple agencies and

regulations. Discussed below are the Environmental Protection Agency (EPA) the Federal Risk Management Plan (FRMP),

the California Accidental Risk Prevention Program (CalARP), and the Occupational Safety and Health Administration

(OSHA).

6.1 Environmental Protection Agency [19] In a 1993 study, the Environmental Protection Agency (EPA) conducted a comprehensive study about the use of

hydrofluoric acid in industry, specifically oil companies. Congress required the EPA to conduct the study in order to identify

potential hazards to public health and the environment by considering the worst-case accidental releases, and to make

recommendations for reducing the hazards.

The EPA regulated HF under several regulations authorized by the Comprehensive Environmental Response,

Compensation, and Liability Act (CERCLA), Title III of the Superfund Amendments and Reauthorization Act (SARA) of

1986 and the Resource Conservation and Recovery Act (RCRA). HF has also been regulated by the Department of

Transportation (DOT) under the Hazardous Materials Transportation Act (HMTA) and the Hazardous Materials

Transportation Uniform Safety Act (HMTUSA).

The EPA study characterized how and where HF is produced and used in the United States. It identified the hazards that

were specific to those uses and processes and assessed the potential hazards to the public and the environment from potential

HF releases. The EPA’s analysis found that the greatest hazards of HF were associated with the manufacture and use of

high concentrated HF (>70%). HF has been heavily regulated under a number of U.S. statutes. An in-depth analysis can be

found in the 1993 study [16].

6.2 Federal Risk Management Plan [28] One of the current pieces of federal legislation that regulates HF is the Federal Risk Management Plan (FRMP) which

implements Section 112(r) of the Clean Air Act (CCA) amendments of 1990. This law allows the EPA to publish regulations

and guidance regarding chemical accident prevention at facilities that use certain hazardous substances. This info is used

by fire, police, and emergency response personnel in case of chemical emergencies


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6.2.1 Risk Management Plans

[28] A RMP must address at minimum these three topics:

1. A Hazard assessment that details the consequences of an accidental release under a variety of conditions, including

worst-case scenarios, and an accident history dating back the last 5 years.

2. A Prevention program which includes safety precautions (such as a SOP), training measures, and facility

maintenance and monitoring.

3. An Emergency response program which includes emergency health care and employee training for informing

response agencies and the public in the case of an accident.

[19] For HF, a RMP is only necessary for facilities that use HF at concentrations above 50%, and use enough HF to surpass

the 1,000 lbs. Threshold Quantity.

6.2.2 General Duty Clause [26] One aspect of Section 112(r) is the General Duty Clause (GDC), which recognizes that owners and operators of facilities

have a responsibility in managing any hazardous chemicals on-site. This responsibility includes: being aware of the hazards

of said chemicals and the consequences of a possible release, designing and maintaining facility safety in order to prevent

accidents, and minimizing the impacts if a release does occur.

With that being said, the General Duty Clause does not provide specific regulatory guidelines for meeting the above

requirements, and cannot be checked against any particular data sets. For example, the GDC does not specify the exact

manner in which an owner need to identify hazards and conclude the consequences of a release. Despite this, a hazard

assessment should include the different types, rates, and durations of potential chemicals releases by using modeling and

dispersion analytical techniques.

To meet the requirements of the GDC, all relevant industry codes and standards must be adopted, though these policies may

not always be enough to indicate a satisfactory attempt at meeting GDC guidelines. In such a case, a unique and tailored

accident prevention program may be necessary depending on the facility. Additional suggestions in meeting GDC

requirements can be found at the EPA website, and the link is provided in the References section (5). Section 113(b) allows

the EPA to require the implementation of these additional safety measures, and to assess penalties of up to $37,500 per day

for each violation.

6.2.3 FRMP Programs

As part of Section 112(r) of the CCA, some programs enacted by the EPA regarding chemical safety were implemented and

are as explained as following:

One of the programs is Chemical Safety Audits, which focuses on the prevention and mitigation of chemical accidents by

reviewing facilities’ programs. These audits are meant to provide compliance assistance towards GDC requirements.

However, a deficiency in these programs can also be cited as a violation of the GDC or overall risk management program.

Another is Accident Investigations, which ideally is able to determine the root cause or system failure that caused the

accident. This information can be used to reduce the likelihood of a recurrence and minimize the consequences if there is a

recurrence. These investigations are led by the Chemical Safety and Hazard Investigation Board, created by Section 112

(r.6) of the CCA.

Lastly, there are RMP Audits. These audits focus on assessing a facility’s RMP for hazard assessment, prevention, and

response. If found necessary, the EPA may require RMP modifications for program improvements.


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6.3 California Accidental Release Prevention (CalARP) [7] The California Accidental Release Prevention Program (CalARP) includes the federal Accidental Release Prevention

Program with additional specifics to the state’s Health and Safety Code (HSC). The purpose of the program is to prevent

the accidental releases of regulated substances, such as HF.

Any stationary source that exceeds the threshold quantity of a regulated substance may be required to develop and submit

a risk management plan (RMP) to determine the potential for and impacts of accidental releases. According to Section

2745.3, the RMP shall include the (1) accidental release prevention and emergency response policies at the stationary source,

(2) the stationary source and regulated substances handled, (3) the general accidental release prevention program and

chemical-specific prevention steps, (4) the five-year accident history, and (5) the emergency response program and the

planned changes to improve safety. In addition, the owner needs to submit a worst-case scenario and analysis on the

Prevention Program for each Program 1, 2, and 3 process and extensive data regarding the chemical such as release rate,

release duration, etc. The data required can be found in Section 2745.4-2745.11.

6.3.1 Hazards Assessment & Five-year Accident History [7] Section 2750.1 - Section 2750.9 discuss the requirements behind the Hazards Assessment and the five-year Accident

History section in the RMP. The assessment must include analysis parameters such as wind speed, ambient

temperature/humidity, height of release, etc. The worst-case scenario must define the largest impacted radius from the center

at the point of release with the population defined as the residential population plus the presence of institutions (such as

schools, hospitals, long term health care facilities, child day care facilities, and prisons), parks and recreational areas, and

major commercial, office, and industrial buildings.

6.3.2 Training, Maintenance, & Compliance Audits [7] Section 2755.4 – Section 2755.6 discuss the requirements behind the Training, Maintenance and Compliance Audits for

the RMP. The owner is responsible for ensuring that each employee has been tested and is competent in the operating

procedures for their designated operation. At least every three years refresher training must be provided to each employee

operating a process. The owner must ensure that the operators are trained in any updated or new procedures.

The owner must train each employee involved with maintaining the mechanical integrity of the process equipment. Any

maintenance contractor must ensure that each contract maintenance worker is trained to perform the maintenance

procedures. Each process equipment must be inspected frequently to follow generally accepted good engineering practices.

The frequency of the inspections should be consistent with the manufacturer’s recommendations.

Every three years, the owner must submit a compliance audit that certifies that they have followed the procedures and

practices developed mentioned in the previous sections. The audit is conducted by at least one person knowledgeable in the

process. The owner should hold the two most recent compliance audit reports.

6.3.3 Contractors [4] Section 2760.12 states that the owner shall obtain and evaluate information regarding the contractor’s safety performance

and programs. The owner should review that each contract employee follows the safety rules and follow safe work practices.

6.4 Occupational Safety and Health Administration [19] The Occupational Safety and Health Administration (OSHA), which is the primary federal agency regarding safety and

health legislation. OSHA sets a number of industry standards, such as:

(1) What information employers must provide employees regarding hazardous chemicals (Hazard Communication

Standard

(2) What personal protective equipment employers must prove and how often it must be inspected (Occupational

Safety and Health Act)

(3) Air contaminants exposure thresholds, stated earlier as 3 ppm for HF (Occupational Safety and Health Act)


Page 18

The OSHA Process Safety Management Standard is a set of requirements which is intended to minimize the consequences

of releases of hazardous chemicals, thereby protecting employees. It includes a written safety compilation, which includes

information on subjects such as chemical hazards and the equipment being used to handle said chemical. Another component

is a process hazards analysis which must be conducted every 5 years. It is a thorough review of potential scenarios of

something gone wrong, and what safeguards are in place in case any such scenario arises. Other elements are a SOP,

employee hazards training, pre-startup equipment safety reviews, and regular mechanical maintenance.

7. Relationship to Hydrochloric Acid [20] One of the most commonly used chemicals in the world, perhaps even more so than hydrofluoric acid, is hydrochloric

acid. Similarly, to HF, HCL is extremely dangerous, with the maximum health and exposure hazard rating possible.

According to OSHA, HCL’s Permissible Exposure Limit is 5 ppm, only slightly above HF’s Limit of 3 ppm. Many of the

standard handling and emergency procedures for HF are applicable for HCL, such as extensive PPE including (but not

limited to): a face shield, acid-resistant apron, gloves, and respirator if using high enough concentrations as to cause fuming

(discussed more below). If HCL makes eye or skin contact, or is inhaled or ingested, it is HIGHLY suggested to seek

medical attention immediately. Specific treatment can be found in the MSDS, which should be immediately available at

any facility handling HCL.

[21] Another way in which HCL is similar to HF, and what makes it especially relevant to this report, is that HCL is produced

at varying concentrations depending on the manner in which it is used, and has different handling protocols depending on

this concentration. HCL becomes more hazardous as concentrations increase simply due to HCL’s corrosive nature, but

what makes higher-concentration HCL especially dangerous is the fact that its evaporation rate also drastically increases.

This drastic increases begins around 15% concentration (depending slightly on pressure), reaching a near 100% evaporation

rate by 39% concentration (and at that point, fuming profusely). Without adequate ventilation or a respirator, inhalation is

extremely likely.

[19], [22] HCL has household purposes, largely cleaning, and these solutions are usually between 10-12%, and often diluted

even further. At higher concentrations, it is used for the production of chlorides, fertilizers and dyes, and has uses in the

photographic, oil, and rubber industries. This bulk, industrial-grade HCL is usually between 30-35%, though it can be

produced at up to 38% concentration. While it is possible to produce solutions with concentrations slightly above 38%, the

solution evaporates so quickly that additional storage and handling requirements are necessary. Under the Federal Risk

Management Plan, any facility handling over 15,000 lbs. of HCL at a concentration above 37% must create an RMP.

[24], [19] Hydrochloric acid is also produced in an anhydrous form, hydrogen chloride gas, a clear colorless gas composed

100% of hydrogen chloride. When exposed to air, it reacts quickly to water moisture in the air and strongly fumes. It can

cause severe respiratory tract, eye, and skin burns. Again, handling procedures and exposure procedures can be found in the

MSDS and are similar to aqueous HCL, though are stricter, especially in regard to respiratory protection. An RMP is

necessary under the FRMP for any facility handling over 5,000 lbs. The purpose of this brief discussion of HCL was to demonstrate that there are already chemicals which have different

standards and protocols depending on the concentration and form of the chemical besides HF. As discussed above, HCL is

a hazardous enough chemical to be heavily federally monitored. However, HCL in a low concentration form is not only

able to be freely purchased, but is regularly used in common household products. Clearly, the dangers these chemicals pose

have already undergone extensive evaluation, yet have been deemed too valuable to outright ban, and HF is no exception.

Furthermore, HCL isn’t under consideration from this bill despite the fact that it fumes at considerably lower concentrations

of HF, and from the bill it appears that large-scale fuming is the primary concern regarding HF’s use. While HF and HCL

undoubtedly pose different dangers, adhering to concentration-based standards for HF would be in no way unprecedented.

8. Findings and Recommendations

Hydrofluoric acid is an extremely dangerous and threatening chemical. According to the U.S. Chemical Safety Board’s and

Cal/OSHA’s investigative reports, the accidents at the Torrance facility could have been avoided if management had


Page 19

followed proper protocol. Instead, the facility manager used an outdated document to avoid existing safety industry

standards and regulations. The CSB concluded its investigative report by saying that substantial changes need to be made

in how refineries are regulated.

Our first recommendation, which is less drastic than this bill, is to more stringently enforce the current federal and state

laws regarding HF. As discussed earlier, there is already an extensive network of standards and regulations for facilities

using HF. The current regulations, when properly followed, tremendously reduce the likelihood of an accident, as seen with

UTC Aerospace and Air Products & Chemicals, which have not even had a minor HF accident affecting the public. On the

other hand, the Torrance refinery incident arose because current standards and regulations were not being adhered to by

management. We propose that to ensure these regulations are followed, the penalty fines associated with violations be

substantially increased. These fines can then be used to offset the costs of the additional and stricter inspections incurred in

this process.

The formation of a HF vapor cloud is possible in large, highly concentrated quantities that are present in large industrial

facilities such as oil refineries. Such a large, dense vapor cloud over a residential area would be absolutely catastrophic, and

is a situation that absolutely must be avoided. However, AB-1759 in its current form is not the optimal way to ensure this.

Relatively dilute HF with concentrations less than 40% do not produce significant vapor concentrations unless superheated

and placed under large amounts of pressure, conditions typically only found in oil refineries or similarly large facilities.

Under standard conditions, such as those found in university laboratories, aqueous HF will begin to fume at concentrations

above 40%, but will not form a dense cloud. Aqueous HF concentration may increase until it reaches its maximum saturation

at 70% (under standard conditions), at which point it is at its most volatile state and reaches maximum fuming. It is at this

concentration and under high pressure conditions that there is a higher probability for the formation of a dense vapor cloud

if a HF release occurs.

We strongly recommend that the bill recognize the difference in threat level that HF poses at difference concentrations, as

is done with other chemicals. The hazard posed by a 30% concentration HF solution cannot reasonably be compared to a

70% concentration HF solution. As such, we propose that the bill follow federal guideline practices and focus on facilities

that handle HF concentrations over 50% such as oil refineries. Due to its effect on fuming, the establishment of a vapor

pressure threshold should be considered as well. Many companies in California, such as Air Products and Chemicals and

UTC Aerospace, responsibly use HF at concentrations less than 50% at standard air pressures, and their working conditions

present minimal public safety threat. To force these companies to halt the use of HF would be catastrophic to California’s

economy, yet would not provide the public safety benefit that the bill seeks.

If our other proposals are not to be followed, our final proposal (and as a last resort) is that the bill should extend the time

period before it goes into effect as to allow for additional time if it is going to force oil refineries to find an alternative to

HF to use in the alkylation process. The United Steel Workers Study has concluded that there are a few alternatives to HF.

The first, which replaces HF with sulfuric acid alkylation, has already been implemented in some refineries, though it has

its drawbacks. As discussed in Section 4.5, sulfuric acid is much safer than HF but it still poses serious hazards for workers,

the public and the environment, and is not for certain an effective alternative. Secondly is solid-acid catalyst alkylation

which has been studied and implemented by a few companies. Another is ionic-liquid alkylation, a process that has been

successfully developed and implemented in Chinese refineries and is in the pilot and production phase. The two processes

are much safer for workers and the public because of it does not use HF or sulfuric acid. However, more research and studies

must be conducted in order to determine if either are a reliable alternative and are able to meet California’s unique gasoline

blend regulation. With all factors considered, there is absolutely no way an alternative will be available by 2017.

Furthermore, any alternative will come at enormous costs, costs which could be enough to force the shutdown of refineries.

8. References

Bill Number AB 1759. Introduced by Assembly Member Rob Bonta. February 2, 2016.

[1] "Cal/OSHA Seeks Huge Penalties in Refinery Explosion - Cal-OSHA.com." CalOSHA Reporter RSS. N.d. [Accessed

April 26, 2016]. http://www.cal-osha.com/Cal-OSHA-Seeks-Huge-Penalties-in-Refinery-Explosion.aspx.


Page 20

[2]"Cal/OSHA Cites ExxonMobil for Unrepaired Leak at Torrance Refinery – Occupational Health &

Safety." Occupational Health & Safety. March 9, 2016. [Accessed April 25, 2016].

https://ohsonline.com/articles/2016/03/09/cal-osha-cites-exxonmobil.aspx.

[3] "CSB Safety Bulletin Says "Managing Change" Is Essential to Safe Chemical Process Operations."

U.S. Chemical Safety Board. August 28, 2001. [Accessed April 25, 2016]. http://www.csb.gov/csb-safety-bulletin-says-

managing-change-is-essential-to-safe-chemical-process-operations/.

[4] Dobis, Jonathan, Williams, Dana and David Bryan Jr." The Effect of Operating Conditions on Corrosion in HF

Alkylation Units". Inspectioneering Journal. May/June 2004. [Accessed May 18, 2016].

[5] Esteves, P. M., C. L. Araujo, B. A. Horta, L. J. Alverez, C. M. Zicovich-Wilson, and A. Ramirez-Solis. "The

Isobutylene-Isobutane Alkylation Process in Liquid HF Revisited." The Journal of Physical Chemistry B 109, no. 26

(2005): 12946-2955. [Accessed May 18, 2016]. Doi: 10.1021/jp051567a.

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9. Appendix

[11], [12] Tables taken from Honeywell MSDS safety sheets.

Documents

INVESTIGATION OF INDUSTRIAL USE OF HYDROFLUORIC ACID IN CALIFORNIA REGARDING LEGISLATIVE BILL AB 1759