On October 10, 2024, a chemical leak occurred at the PEMEX Deer Park Refinery where two people died and about 35 others were injured due to the release of hydrogen sulfide (H₂S). This incident prompted a city-wide shelter-in-place; and later that day the City of Deer Park reassured the public via social media: “We are aware of the odor but there is no hazard to the community.”

This raises an important question: How can it be deemed safe to smell a gas in certain circumstances, particularly when fatalities had occurred that day due to that exact gas? Because during industrial incidents, like the chemical leak at the PEMEX Deer Park Refinery, H₂S concentrations in areas accessible to the public are typically diluted to levels well below hazardous thresholds. H₂S toxicity is primarily due to its ability to interfere with cellular respiration by inhibiting cytochrome oxidase enzymes, which are critical for energy production in cells. At low levels, the inhibition of mitochondrial enzymes is reversible; and once H₂S is cleared by human metabolism, cellular respiration and energy production return to normal.

Humans can detect H₂S at concentrations as low as 0.00047 ppm (parts per million) or 0.47 ppb (parts per billion) – which is often described as having a “rotten egg” smell – well below levels that pose a health risk. This sensitivity allows individuals to notice the gas even when it is present in concentrations far too low to cause harm. Exposure to levels exceeding 300 ppm can cause unconsciousness and death within minutes, due to respiratory failure. Paradoxically for human safety at concentrations exceeding approximately 100-150 ppm, H₂S rapidly desensitizes the olfactory nerves, leading to a loss of the ability to smell the gas even at toxic concentrations. Workers thus may unknowingly remain in a hazardous environment, believing that the gas leak stopped and the smell dissipated into the air – increasing their risk of severe health effects, including respiratory failure, unconsciousness, or death.

The sense of smell plays a critical role in our daily lives and in safety and health, particularly in industrial and occupational environments where hazardous chemicals are present. In this edition of HETI Horizons, we explore the fascinating intricacies of olfactory perception, its implications – from normal function (normosmia) to altered conditions (e.g., anosmia and parosmia), as well as factors influencing odor thresholds.

What Are Odor Thresholds?

Odor thresholds refer to the minimum concentration of a substance in air that is detectable by the human nose. This is typically divided into two categories:

• Detection Threshold: The lowest concentration at which a person can detect an odor but cannot
  identify it.
• Recognition Threshold: The concentration at which an odor is recognizable and can be associated with a particular substance.

In occupational safety, detection thresholds might alert someone to the presence of a chemical (e.g., “I smell something”), while recognition thresholds are critical for identifying specific hazards (e.g., “This smells like hydrogen sulfide, a toxic gas”). These thresholds vary significantly among individuals due to a range of physiological and environmental factors.

Olfactory Disorders: From Anosmia to Phantosmia

The sense of smell is a dynamic and complex system, and several disorders can impact it:

• Normosmia: Normal smell perception. For example, a worker in a chemical plant detects a faint odor
  of natural gas, triggering immediate action to check for leaks. The normal sense of smell allows
  identification of potential hazards before they become critical.
• Anosmia: Complete loss of smell, often observed in viral infections such as COVID-19. For example, a
  lab technician who has lost their sense of smell due to COVID-19 cannot detect a gas leak from a
  malfunctioning cylinder – potentially putting themselves and colleagues at risk. This highlights the need
  for backup safety measures like gas detectors.
• Hyposmia: Reduced sensitivity to odors. For example, a painter working with
  solvents may only faintly notice the strong chemical odors in the workspace, leading
  to prolonged exposure without realizing the potential hazard. This can result in
  overexposure to harmful fumes.
• Hyperosmia: Heightened sensitivity to smells. For example, an office worker
  may find the smell of cleaning products in a freshly sanitized office overwhelmingly
  strong – causing discomfort, nausea, or headaches. This could necessitate
  accommodations, such as using low-odor cleaning agents.
• Parosmia: Distorted smell perception, often making pleasant odors seem unpleasant. For example, a
  cleaning staff member perceives the pleasant smell of lemon-scented cleaning solutions as sour or
  chemical-like after recovering from an illness – causing discomfort during their tasks.
• Phantosmia: The perception of odors that are not present. For example, a factory worker suddenly
  perceives the smell of burning rubber during their shift, even though there are no fires or machinery
  issues. This could cause unnecessary panic or misdirected safety checks – affecting workflow
  efficiency.

The COVID-19 pandemic brought widespread attention to these disorders, as many affected individuals reported anosmia or parosmia, with some experiencing prolonged recovery periods. Such conditions may affect workplace safety, as workers may fail to detect harmful chemical odors.

Individual Variability in Odor Perception

A wide range of factors influence odor thresholds, including:

• Gender: Women often exhibit greater sensitivity to odors than men.
• Age: Olfactory sensitivity declines with age, impacting recognition thresholds.
• Smoking: Long-term smoking damages olfactory receptors, reducing smell
  perception.
• Pregnancy: Hormonal changes can heighten sensitivity to certain odors.

Individual variability underscores the importance of tailored safety protocols in workplaces.
New technologies in gas detection provide more sensitive, real-time monitoring of odor-causing substances like hydrogen sulfide, ammonia, and volatile organic compounds (VOCs). These devices can now detect concentrations far below regulatory thresholds, improving early warning systems. Also, personal monitoring devices, often integrated with wireless systems, allow workers to receive alerts when odor thresholds are exceeded – reducing reliance on human olfactory perception, which can be impaired by conditions like anosmia or olfactory fatigue.

HETI…Here to Help

HETI can assist in understanding the complexities of odor thresholds and the various factors that influence them. By leveraging our expertise, we can help clients implement enhanced safety measures, safeguard their workforce, and promote a healthier and more secure workplace environment. HETI can provide tailored recommendations for air quality monitoring systems – including gas detectors and alarm thresholds calibrated to detect hazardous substances before they pose a risk. We can also conduct workshops to educate workers about the importance of odor perception in safety – including conditions like olfactory fatigue, hyposmia, and anosmia, which can impact hazard detection.

To find out more about this and other HETI industrial hygiene services,
please contact us.
Daniel Farcas, PhD, CIH, CSP, CHMM
Senior Industrial Hygienist

Managing large, complex environmental/pollution claims can be extremely challenging. Whether it’s a tanker truck roll-over, chemical plant fire, or train derailment, effective management of the response and cleanup can make a substantial impact on the outcome of the loss. This edition of HETI Horizons provides an overview of specific methods and practices that can be employed to minimize liabilities, control costs, and ensure correct application of the policy.

Initial Response

Whenever an environmental emergency occurs, swift and coordinated action is crucial. Immediate mobilization of qualified representatives ensures that carriers and insured parties have the needed support on-site when it’s needed most. This is especially critical within the first 48 hours, as emergency response efforts can be extremely dynamic and costly. The goal is to establish a consistent presence, to become an advocate of the insured, and to assist with facilitating efficient communications and clear lines of responsibility. Early reporting from an “on the ground” perspective is essential to assist the insurance carrier in determining policy applicability, assessing coverage, and gaining knowledge of the overall risks associated with the loss. Understanding the risk environment, the response effort, and the regulatory expectations will guide the ability to assist the insured in streamlining the response effort – assuring the most efficient, cost effective operation possible.

Risk Evaluation

Understanding the insured’s overall risks is fundamental. A comprehensive risk evaluation should be performed immediately following the event to identify and assess on-site and off-site impacts, affected third parties, potential business interruption impact, and regulatory liability. It is also important to determine whether other insurance policies, such as property or general liability, may apply to the claim and assess the cooperation levels with other carriers. Proper subrogation and risk transfer evaluation, including the preservation of evidence and review of contracts, are essential to minimizing exposure.

Effort Optimization

Maintaining momentum throughout the claims process requires ongoing communication. Establishing expectations on day one and adhering to an operational structure throughout the remediation process are vital. Regular follow-ups and updates prevent surprises and keep the claim on track. Developing relationships with emergency response contractors, regulators and other carriers will assist in streamlining the process ensuring readiness and assuring that an efficient and cost-effective posture is maintained. Early discussions between the insured, brokers, and claims adjusters help clarify documentation requirements and potential red flags.

Establishing an organized operational structure for all phases of response and remediation efforts is critical to manage resources, maintain clear lines of technical responsibilities, and accurately segregate on-site activity among funding sources. Additionally, on-site monitoring ensures that efforts remain cost-effective and aligned with expectations. Regular communications with the insured and remedial contractors should encourage efficiencies – such as utilization of alternative methodologies for waste management, treatment, and disposal.

Cost Allocation

Cost and expense allocation is another critical component in the claim management process. Typically, not all activity taking place on-site is considered applicable to a single policy. For example, decommissioning mechanical components, de-inventory of unaffected products, and demolition of structures may not be covered by an environmental policy. Therefore, daily activity reports and other documentation are necessary for the defensible allocation of applicable costs.

Contractors should be required to submit detailed invoices that can be clearly correlated with daily activity reports, field notes, and waste inventory. The assessment of charges should also include verifying their necessity, reasonableness, and adherence to industry standards.

Proper cost allocation and accurate documentation often yields significant cost reductions by parsing reasonable and necessary costs associated with activity applicable to the policy. An Invoice Evaluation Report is an invaluable tool to illustrate the effectiveness of on-site monitoring, documentation and collaboration throughout the process, and present costs that have been determined to be reasonable, necessary and applicable to the policy.

By employing these strategies, organizations can effectively manage environmental claims, control costs, and minimize liabilities – ensuring a balanced approach to environmental emergency response and remediation claims.

Services from HETI

HETI’s staff possesses extensive experience in responding to and managing environmental incident response and remediation projects on behalf of dozens of insurance carriers – representing their interests and, indirectly, those of their clients. HETI has subsequently helped its customers in significantly reducing overall risk, both short-term and long-term, as well as assisted in significant cost savings throughout the life of environmental/pollution claims.

To find out more about HETI’s emergency response, remediation,
and claim support services, please contact us.
James Rothrock
Senior Geologist/Senior Environmental Scientist
Phone: 978.263.4044
development@hetiservices.com

With the first generation of photovoltaic cells nearing their useful life (typically 25 to 30 years), the volume of solar panel (photovoltaic cell) waste has increased in the last few years. This trend will continue. Because of the construction of solar panels, a certain amount of processing is required before the panel components can be recycled. With the projected growth of solar technologies, raw material availability could be constrained. So, solar panel recycling will be increasingly important.

Solar Panel Technologies

A typical solar panel uses silicon crystals as a semi-conductor which converts light into electricity. The surface of each crystalline photovoltaic module – often a silicon crystal – is crisscrossed by thin strips of metal (silver and others) which move electricity into the panel’s copper wiring. The solar cells are encapsulated in a protective transparent barrier called EVA (ethylene-vinyl acetate) which is inexpensive and has good optical properties. A layer of glass is placed on top and a plastic backsheet – commonly polyethylene terephthalate (PET) – goes on the bottom. These encapsulating layers provide protection for the solar cells from harsh environments. The entire assembly is contained in an aluminum frame. Separation of the solar panel components can be a challenging process – contributing to the difficulties and costs in their recycling.

Of the three types of solar panels commonly found today: monocrystalline is the most efficient; polycrystalline the cheapest; and thin-film panels the most portable.

First-generation solar panels are crystalline silicon (c-Si) panels, which account for approximately 95% of all solar panels produced to date. Because silicon is readily available, c-Si panels are more affordable and highly efficient. The two types of c-Si panels are: monocrystalline, which can reach efficiencies of more than 20%; and polycrystalline, which tends to be below 20% efficient.

A monocrystalline solar panel is made from single crystal solar cells or “wafers.” Monocrystalline wafers are created from a single silicon crystal formed into a cylindrical silicon ingot. A monocrystalline cell’s composition provides more room for the electrons to move – making it more efficient. However, during the manufacturing of monocrystalline panels, the process of solidification of silicon must be controlled very carefully – increasing production costs. So, while monocrystalline solar cells tend to be more efficient than polycrystalline cells, their costs are higher.

Polycrystalline silicon solar panels – also known as “multi-crystalline” or many-crystals – consist of wafers constructed by melting many silicon fragments together into square molds. The resulting wafers are then cut into individual cells. Because the manufacturing process is much simpler, compared to monocrystalline panels, these panels tend to be less expensive.

Thin-film solar cell (TFSC) panels consist of a single or multiple layers of photovoltaic elements on top of a surface comprised of a variety of glass, plastic, or metal. Compared to first-generation c-Si panels, TFSCs require less semiconductor material. TFSCs use strongly light-absorbing materials – such as cadmium telluride, copper indium gallium selenide, amorphous silicon, and gallium arsenide. Because they are less affected by higher temperatures, TFSCs have lower thermal photovoltaic losses than c-Si panels; but they tend to be more expensive. Currently, TFSC panels have a small share of the solar panel market and are primarily used in mobile applications.

Regulatory Environment

When discarded, solar panels are classified as solid waste and fall under existing federal solid and hazardous waste regulations.

Some solar panels may contain enough metals (e.g., lead) to meet the definition of hazardous waste under the Resource Conservation and Recovery Act (RCRA). In such cases, the generator may use their own knowledge or may determine if the solar panels are hazardous waste by performing appropriate testing, such as toxicity characteristic leaching procedure (TCLP).

Solar panels can be recycled using the transfer-based exclusion if the state in which the solar panel waste is generated and recycled has adopted the 2015 or 2018 Definition of Solid Waste Rule. However, the requirements found in Environmental Protection Agency (EPA) Regulation 40 CFR, Section 261.4(a)(24) must be followed.

Solar panels are not a federal universal waste and cannot be managed as such. However, some states, such as California and Hawaii, have added solar panels as state-only universal waste. In part in response to a petition submitted by a broad coalition of industry associations to regulate solar panels as universal waste and to improve management and recycling of solar panels, EPA is drafting streamlined solar panel end-of-life management requirements – likely to be published in the summer of 2025 – by adding hazardous waste solar panels to the universal waste regulations (CFR 40 Part 273). This should improve management of all solar panel waste and encourage recycling.

Services from HETI

HETI’s staff continually reviews new and proposed changes to regulations and standards to make sure we have current knowledge of compliance and environmental health & safety (EHS) issues. We have extensive experience in supporting our clients though a comprehensive range of regulatory and other services. So, whether there is a need for waste management evaluation, permitting, or other regulatory support, HETI’s professionals are ready to help.

To find out more about HETI’s EHS and regulatory support services, please contact us.
Carmelo Blazekovic
Senior Geologist/Senior Environmental Scientist

In the little town of West, Texas, people’s lives were changed forever on April 17, 2013, when a catastrophic explosion ripped through a small fertilizer manufacturing facility. This plant had not followed the Risk Management Plan (RMP), as required by the Environmental Protection Agency (EPA) under the 1990 Clean Air Act; and responders did not know what chemicals were at the plant and the hazards they presented to appropriately contain the fire and protect themselves and the community. And if the plant had followed the RMP procedures, they would have had basic steps in place to prevent this hazardous outcome.

In this incident, the fertilizer facility had 40-60 tons of bulk ammonium nitrate in open bins, which exploded after a fire erupted in the building. Twelve firefighters and three members of the public died, and 260 people were injured. The explosion was felt up to 30 miles away and businesses, apartments, houses, a nursing home, and a school were damaged or destroyed. The plant had been built in 1961 and homes and businesses were allowed to be constructed close to the facility.

In another catastrophic event in November 2019 in Port Neches, Texas, a dangerous chemical in a 16-inch pipe was not moving, which caused a polymer to build up for more than 100 days. This led to an explosion – leaving a fire that burned for two months due to the presence of high-purity butadiene. About 50,00 people needed to be evacuated. After a comprehensive investigation of these explosions and several other severe chemical plant accidents, Executive Order 13650 directed the federal government to carry out several tasks – including modification of the RMP rule, intended to prevent chemical incidents.

Changes to the RMP Rule

The ensuing changes to the RMP rule – known as the Safer Communities by Chemical Accident Prevention (SCCAP) rule – were finalized on February 27, 2024, and went into effect May 10, 2024. The new modifications aim to protect the community, chemical plant owners/operators/workers, and emergency responders from chemical accidents. The amendments are intended to:

• Address and improve accident prevention program elements
• Enhance emergency preparedness requirements
• Ensure Local Emergency Planning Committees (LEPCs), local emergency response officials, and the public can
  access information in a user-friendly format to help them understand the risks at RMP facilities and better prepare
  for emergencies

EPA’s RMP Rule applies to approximately 11,470 U. S. facilities that use extremely hazardous substances.
Approximately 131 million people live within three miles of an RMP facility.

The final RMP Rule includes several changes – including:
     Safer Technologies
Facilities in high-accident industries must evaluate safer technologies and alternatives and implement reliable safeguards in industry sectors with high accident rates.
     Employee Participation
Facilities must improve employee participation training and decision-making in accident prevention. Employees can anonymously report unaddressed hazards.
     Third-party Audits
Facilities that have reported accidents must undergo third-party compliance audits and root-cause analyses.
     Information Sharing
Improved information sharing between facilities, communities, and emergency responders.
     Public Disclosure
Facilities must provide chemical hazard information to the public within 45 days of a request. EPA has also released an online tool that allows users to search for RMP facilities in their locality. Controls are in place to protect trade secrets.

What is the Risk Management Program

The EPA RMP is a guidance for chemical accident prevention for facilities that meet certain risk criteria. It consists of five parts:

1. Identify the Risk. The initial step is identifying the risks that the business has in its daily operations. The Rule includes a List of Regulated Substances under section 112 (r) of the Clean Air Act. These regulated substances are also subject to the requirements of the General Duty Clause promulgated by the Occupational Safety & Health Administration (OSHA). In addition to the federal list of chemicals, where the Clean Air Act Section 112 (r) has been delegated to a state, that state may have additional requirements.
2. Determine the Program Level of 1, 2 or 3. Program Level 1 covers processes that would not affect the public in the worst-case scenario. Level 2 covers operations that do not fit in Level 1 – often having relatively simple processes and may be located at small businesses. They have basic prevention practices but with less documentation and recordkeeping than Level 3. Program Level 3 covers operations that have the most hazardous processes and require the most hazard assessments and hazard prevention plans.
3. Evaluate the Risk by a Risk Assessment. This can include: a Hazard Assessment or a Process Hazard Analysis (PHA) that details the potential effects of an accidental release, an accident history of the last five years, and an evaluation of worst-case and alternative accidental releases; a Prevention Program that includes safety precautions and maintenance, monitoring, and employee training; and an Emergency Response Program that spells out emergency health care, employee training measures and procedures for informing the public and response agencies (such as the fire department, LEPCs, etc.) should an accident occur.
4. Train Employees about the risks.
5. Maintain, Monitor and Review the Risk. A RMP should be updated at complex organizations once a year, unless a major change in the process or chemicals present triggers a review. EPA requires that a Risk Management Plan be revised and resubmitted to EPA every five years.

HETI Risk Management Services

HETI has extensive expertise and experience in the implementation and management of facility-specific safety operations and procedures, including requirements needed for ensuring and maintaining compliance with EPA’s RMP. Our staff can provide a wide range of RMP services – including developing/reviewing Risk Management Plans, Risk Assessments, Hazard Assessments, Facility Audits, Emergency Response Programs, Training for Onsite Risks, and Root Cause Analyses.

To find out more about HETI’s risk management program and
regulatory support services, please contact us.
Jacqueline Armstrong
Senior Industrial Risk Manager
Phone: 978.263.4044
development@hetiservices.com

Chromium is a naturally occurring metal that can be found in many metal alloys and salts. It is even used as a dietary supplement in over-the-counter preparations. Occupational exposures to chromium can occur in the form of dusts, fumes and mists – including total chromium, trivalent chromium (III), hexavalent chromium (VI), chromic acid, chromates and dichromates. In 1976 the National Institutes of Occupational Safety and Health (NIOSH) published its Criteria for Recommended Standard for Occupational Exposure to Chromium VI based on its carcinogenicity. The International Agency for Research on Cancer has listed Chromium VI as a carcinogen based on an association with lung cancer. Following their rulemaking process in 2006, the Occupational Safety and Health Administration (OSHA) issued their comprehensive standards for Chromium VI. It is one of a handful of standards for health hazards issued by OSHA that have many requirements for employers beyond just establishing eight-hour time-weighted-average (8Hr-TWA) permissible exposure limits (PELs).

Uses of Chrome VI

Chrome VI is used as a pigment in paints and in various applications for its resistance to
corrosion. Spray painting of planes and ships was a common use of Chrome VI being
applied as a mist. It is also applied to bridges and structures exposed to saltwater.
Cutting or grinding on these surfaces can release airborne dust and fumes. Stainless
steel commonly contains Chrome VI; so hot work will generate Chrome VI fumes, and
grinding or cutting can produce airborne dust. Chrome VI is also used in the plating
industry for coating metal parts with chromic acid as well as many other applications.

What Are the Steps for OSHA Compliance

The first step for employers is to review the Safety Data Sheets for chemicals, products and base materials used in their facilities for the presence of Chrome VI. If present, then an industrial hygiene air sampling plan will need to be developed and implemented with samples analyzed by an AIHA-accredited laboratory – following the strict rules for rapid handling and analysis. The results will then be compared to the OSHA action level of 2.5 micrograms per cubic meter of air (ug/m3) and PEL of 5.0 ug/m3 for 8Hr-TWA exposures.

If the results are at or over the action level, the air monitoring will need to be repeated every six months until such time that two rounds of testing have results below the action level. Employees that are exposed will require training on the health hazards (lung cancer, cancer, and damages to the nose and nasal passageways) of Chrome VI, results of the air testing, steps they can take to reduce exposures, proper use of personal protective equipment (PPE), and the need to employ good hygiene practices. If employees are exposed above the action level for more than 30 days per year, the OSHA standard also calls for a medical surveillance program for those employees.

If the results are at or over the PEL, the air monitoring will need to be repeated every three months until such time that two rounds of testing have results below the PEL. In addition to the steps listed above, the use of respiratory protection, medical evaluations, and using change rooms and showers to minimize skin contact will be required. The employer will also have to document steps being taken to reduce exposures to Chrome VI. These may include substitution of materials with no or less Chrome VI content, engineering controls (such as localized or general ventilation) and proper housekeeping efforts. Many welding and brazing systems can be equipped with close-capture ventilation. Work surfaces will need to be maintained as free as practical from the accumulation of Chrome VI. Work areas with potential exposures at or over the PEL will need to be demarcated as “regulated areas” – which indicates PPE is required and decontamination is a must when leaving the regulated area before putting on street clothing, eating, drinking, smoking or applying cosmetics.

Other OSHA standards may also be applicable to Chrome Vi exposures – including Hazard Communication; Dipping and Coating Operations; and Ventilation in Welding, Cutting and Heating (hot work) Operations.

Conclusion

Compliance with OSHA’s comprehensive standard for occupational exposure to Chrome VI is critical in protecting long-term worker health. Training is a vital component, so that workers understand the health effects of overexposure to Chrome VI, proper use of engineering controls to reduce exposures, personal hygiene requirements, and the proper use of selected PPE. Based on exposure levels, medical surveillance by trained occupational health professionals may be required. Employers will also need to rely on an industrial hygienist
to assist with the proper evaluation of airborne exposures to Chrome VI, as well as the design and evaluation of engineering controls such as localized exhaust systems. Exposure evaluations are required initially and depending on exposure levels repeated every three or six months.

HETI…Here to Help

HETI can help businesses comply with OSHA requirements, ensure safe workplaces, and avoid costly penalties. By offering customized training programs, employing expert trainers, ensuring comprehensive compliance documentation, and providing continuous support, HETI serves as an essential partner for businesses aiming to meet regulatory requirements and create safe working environments.

References:
Small Compliance Guide for Hexavalent Chromium OSHA 3320-10N
NIOSH Criteria for a Recommended Standard for Occupational Exposure to Chromium VI, 1975
SGS Galson Sampling Guide Hexavalent Chromium updated OSHA ID 125 for Hexavalent Chromium, 2006
OSHA 29 CFR 1910.1026 for General Industry, 1926.1126 for Construction and 1915.1026 for Maritime Industries

To find out more about this and other HETI industrial hygiene services, please contact us.
Dennis Francoeur, Jr., CIH, CSP, CMI
Senior Industrial Hygienist
Phone: 978.263.4044
development@hetiservices.com

The Toxic Substances Control Act (TSCA) was enacted in 1976 and provides the Environmental Protection Agency (EPA) with “authority to require reporting, recordkeeping and testing requirements, and restrictions relating to chemical substances and/or mixtures. Certain substances are generally excluded from TSCA, including, among others, food, drugs, cosmetics and pesticides”.1

TSCA provides EPA with the authority to regulate entities – including distributors; manufacturers (including importers) and processors (e.g., formulators); commercial users (workplaces and workers); and entities disposing of chemicals for commercial purposes.

Background/History

Under TSCA, EPA has authority to regulate at the manufacturing, processing and distribution levels in the supply chain to eliminate or restrict the availability of chemicals and chemical-containing products for consumer use. These authorities allow EPA to regulate at key points in the supply chain to effectively address unreasonable risks to consumers. However, EPA cannot directly regulate consumer users. 2

In June 2016, Congress amended TSCA with the Frank R. Lautenberg Chemical Safety for the 21st Century Act. This law required EPA to evaluate and address unreasonable risks from chemicals currently in commerce to protect the public while outlining a predictable and comprehensive path for the regulated community. Later that year, methylene chloride, along with nine other chemicals, was identified for risk evaluation. These chemicals are commonly referred to as the “First 10”; and methylene chloride was the first of those to publish a proposed rulemaking under TSCA – with EPA determining that it presents an unreasonable risk under its conditions of use. 2

In March 2019, EPA issued a final rule to prohibit the manufacture (including import), processing, and distribution of methylene chloride for consumer paint and coating removal – requiring manufacturers, processors, and distributors to notify retailers and others in their supply chains of the prohibitions and to maintain records.1

To further protect human health, on July 8, 2024, EPA issued a new rule for methylene chloride 3, expanding workplace protections under TSCA that would:

• Prohibit the manufacturing (including import), processing, and distribution in commerce of methylene chloride for all consumer use and most industrial and commercial uses.
• Require a Workplace Chemical Protection Program (WCPP) for 13 methylene chloride conditions of use.
• Identify a de minimis threshold of 0.1% for products containing methylene chloride for the prohibitions and restrictions on methylene chloride.
• Require recordkeeping and downstream notification requirements for manufacturing (including import), processing, and distribution in commerce of methylene chloride.
• Provide a 10-year time-limited exemption under TSCA section 6(g) for emergency use of methylene chloride in furtherance of the National Aeronautics and Space Administration’s (NASA) mission. 3

Why Methylene Chloride?

Methylene chloride is an acutely lethal neurotoxicant, and chronic exposure can affect liver function and cause cancer. According to a 35-year study published by EPA in June 2021, acute methylene chloride exposure resulted in at least 85 occupational deaths in the U.S. between 1985-2018 – with the most recent in June 2020. EPA found that unreasonable risk from methylene chloride is driven by risks to workers, consumers, and bystanders for 52 of the 53 conditions of use. 3 [TSCA defines “condition of use” as “the circumstances…under which a chemical substance is intended, known, or reasonably foreseen to be manufactured, processed, distributed in commerce, used or disposed of”.]

EPA’s Workplace Chemical Protection Program

EPA determined that the WCPP will protect people from unreasonable risk posed by occupational exposures from certain conditions of use and that workers are one of the potentially exposed or susceptible subpopulations (PESS) under TSCA. EPA consulted with the Occupational Safety & Health Administration (OSHA) and the National Institute for Occupational Safety & Health (NIOSH), who coordinated on WCPP development and aligned
requirements where possible.

According to the EPA, multiple factors were considered in deciding risk management for industrial and commercial conditions of use. Uncertainty regarding ability to comply with an exposure limit or preventing direct dermal contact can influence whether a condition of use is considered to be a candidate for WCPP or whether prohibition is more appropriate.4 Requirements of a methylene chloride WCPP – and key compliance dates, as appropriate –include:

• Exposure limits – Inhalation exposure limits of methylene chloride, called the EPA existing chemical exposure limit (ECEL) and EPA short term exposure limit (EPA STEL) must be met by August 1, 2025. [The ECEL is two parts per million (ppm), or 8 mg/m3, as an eight-hour time-weighted average (TWA); the EPA STEL is 16 ppm, or 57 mg/m3, as a 15-minute TWA.]
• Initial and periodic exposure monitoring – Workplace air concentrations of methylene chloride must be determined through personal breathing zone samples by May 5, 2025.
• Establishment of a regulated area – Owner/operator must mark areas where airborne concentrations of methylene chloride exceed, or there is a reasonable possibility they may exceed, the inhalation exposure limits.
• Development and communication of an exposure control plan – with the following components completed by October 30, 2025:
  • Identification of exposure controls
  • Description of exposure control implementation,
  • Description of the regulated area(s) and authorized entry
  • Description of measures to ensure effective controls
  • Procedures for responding to any potential changes that may introduce additional methylene chloride exposure
• Respirator selection criteria – If respiratory protection is needed, supplied-air respirators must be used for methylene chloride. This rule does NOT permit the use of air-purifying respirators due to the short service life of chemical cartridges when used for methylene chloride exposure.
• Recordkeeping and downstream notification – This includes recordkeeping and notification to persons potentially exposed to methylene chloride of the results of workplace exposure monitoring activities, exposure incidents, and the steps taken or to be taken to protect them from exposure.5

According to EPA, the methylene chloride WCPP applies to Owners or Operators and Potentially Exposed Persons which is a broader definition than “employers”.3

Conclusion

Under the final rule, EPA’s regulation of methylene chloride is far-reaching and includes a significant impact on regulating the workplace. The new regulation provides lower exposure limits and stricter monitoring of the workplace for those commercial uses that will not be “banned”. The rule also puts into place the prohibition of many uses of methylene chloride effective July 8, 2024.

Additional Resources from HETI

HETI’s industrial hygiene and safety professionals are available to assist clients with a variety of services to help develop and implement a Methylene Chloride Workplace Chemical Protection Program in accordance with the new TSCA rule. Whether the need is for written programs and/or industrial hygiene assessments, we are here to help.

For further information on HETI’s environmental health & safety services, please contact us.

Mark Ostapczuk, CIH, CSP
Director – Life Sciences Practice

Phone: 978.263.4044
development@hetiservices.com

Resources:

1Risk Management for Methylene Chloride | US EPA
2Summary of the Toxic Substances Control Act | US EPA
3The Methylene Chloride Rule | US EPA
4U.S. EPA Webinar on Proposed Regulation of Methylene Chloride under the Toxic Substance Control Act (TSCA)
5A Guide To Complying with the 2024 Methylene Chloride Regulation under the Toxic Substances Control Act (TSCA)
[RIN 2070-AK70, mecl-compliance-guide.pdf (epa.gov)]

Effective training is a cornerstone of this mission: providing workers with the knowledge and skills to perform their jobs safely and to understand the hazards they might face. In this edition of HETI Horizons, we will explore the key aspects of the Occupational Safety & Health Administration (OSHA) training requirements – including who needs training, what topics are covered, and how training should be conducted and documented.
OSHA continuously updates and refines its training requirements to address emerging workplace hazards and improve safety standards. Here are some of the recent updates and trends in those requirements:

• OSHA introduced Emergency Temporary Standards to address the COVID-19 pandemic, particularly focusing on healthcare settings. These standards require employers to implement a COVID-19 plan, screen employees, and provide proper personal protective equipment (PPE) and training on infection control practices.
•  OSHA has been focusing on workplace violence, particularly in healthcare and social services. The agency is considering new standards that would require employers to develop and implement violence prevention plans, including training for workers on recognizing and de-escalating potentially violent situations.
• OSHA refers to the NFPA 70 Standard for electrical safety in the workplace. Recent updates to this standard require more comprehensive training on electrical safety practices, arc flash hazards, and the proper use of electrical PPE.

Who Needs OSHA Training?

OSHA training requirements are designed to cover a wide range of industries and job
functions. Virtually every worker in the United States could benefit from some form of OSHA
training, but specific requirements vary depending on the nature of the job and the
associated risks. Key groups that typically require OSHA training include:

• General Industry Workers: This broad category includes workers in sectors such as
  manufacturing, healthcare, and warehousing. OSHA’s General Industry Standards (29 CFR 1910) specify the training needed for various hazards these workers might encounter.
• Construction Workers: Given the high-risk nature of construction work, OSHA has developed specific standards (29 CFR 1926) that mandate training on hazards unique to this field – such as fall protection, scaffolding, and trenching.
• Maritime Workers: Maritime industry workers must be trained according to OSHA’s Maritime Standards (29 CFR 1915, 1917, and 1918), which address risks related to shipyard employment, marine terminals, and longshoring.
• Agricultural Workers: OSHA’s Agriculture Standards (29 CFR 1928) require training for hazards like machinery, pesticides, and grain handling.

What Topics Are Covered?

The topics covered in OSHA training programs are extensive and tailored to the specific hazards of different industries. Some of the key areas include:

• Hazard Communication: Workers must be trained to understand and identify chemical
  hazards, read labels and safety data sheets, and know the procedures for handling hazardous
  substances safely.
• Personal Protective Equipment: Training on the correct selection, use, maintenance, and
  disposal of PPE is crucial to protect workers from physical, chemical, and biological hazards.
  The employer must ensure that each employee can demonstrate knowledge of their respirator’s
  proper fit, usage, or maintenance.
• Emergency Action Plans: Employees must be trained on how to respond to various emergencies – including fires, chemical spills, and natural disasters. This includes evacuation procedures and the use of emergency equipment.
• Lockout/Tagout Procedures: For workers involved in the maintenance and servicing of machinery, training on lockout/tagout procedures is essential to prevent accidental machine start-up and ensure energy sources are safely controlled.
• Fall Protection: In industries such as construction, training on fall protection systems and the correct use of harnesses, guardrails, and nets is vital to prevent fall-related injuries and fatalities.

How Should Training Be Conducted?

Effective OSHA training should be comprehensive, engaging, and tailored to the specific needs of the
workforce. Here are some key principles for conducting training:

• Qualified Trainers: Training should be conducted by individuals who have the necessary knowledge,
  experience, and teaching skills to effectively communicate safety concepts and practices.
• Interactive and Practical: Training sessions should include interactive elements such as hands-on
  demonstrations, real-life scenarios, and practical exercises – to ensure workers can apply what they have learned in their daily tasks.
• Language and Literacy Considerations: To be effective, training must be understandable to all
  workers. This means providing instruction in the workers’ primary languages and considering literacy levels.
• Regular and Ongoing: Initial training should be followed by regular refresher courses to reinforce safety concepts and keep up with any changes in regulations or workplace conditions.

Documentation and Compliance

Proper documentation of OSHA training is essential for demonstrating compliance with regulations and for keeping track of workers’ training history. Key documentation practices include:

• Training Records: Maintain detailed records of all training sessions – including dates, topics covered, trainer information, and participant names.
• Certificates of Completion: Provide certificates or other proof of training completion to employees, which can be useful for compliance verification and employee records.
• Regular Audits: Conduct regular audits of training programs and records to ensure ongoing compliance with OSHA standards and to identify any areas for improvement.

HETI…Here to Help

In conclusion, OSHA training is a vital component of workplace safety – equipping workers with the
knowledge and skills they need to protect themselves and their colleagues from hazards. By adhering to OSHA’s training requirements, employers can create a safer work environment, reduce the risk of accidents and injuries, comply with federal regulations, and demonstrate their ongoing commitment to workplace health and safety.
HETI can help businesses comply with OSHA training requirements, ensure safe workplaces, and avoid costly penalties. By offering customized training programs, employing expert trainers, ensuring
comprehensive compliance documentation, and providing continuous support, HETI serves as an essential partner for businesses aiming to meet regulatory requirements and create safe working environments.

1,4-Dioxane, a highly mobile compound found in various manufacturing processes and consumer products, has drawn significant attention recently. Classified by the United States Environmental Protection Agency (USEPA) as “likely to be carcinogenic to humans” by all routes of exposure, its properties present challenges for characterization and treatment – sparking concerns about its potential impact on human health and the environment.

What is 1,4-Dioxane?

A volatile, flammable liquid, 1,4-dioxane is a man-made organic compound. Its high mobility in soils and rapid migration in groundwater, coupled with its resistance to subsurface biodegradation, pose environmental challenges. While it shares similarities with “forever chemicals” like PFAS, 1,4-dioxane does not bioaccumulate in plants or animals over time, distinguishing it from true “forever chemicals.”

Industrial Applications and Consumer Products

Since the 1950s, 1,4-dioxane has primarily been used as a stabilizer in industrial solvents. While restrictions in drinking water, groundwater, and other environmental regulations have impacted industrial reliance on 1,4-dioxane, it is currently still in use in certain manufacturing processes – including:

• Solvent for paper, cotton, and textile processing
• Chemical manufacturing and stabilizing in chlorinated solvents
• Solvent for paints, dyes, greases, antifreeze, and aircraft deicing fluids
• Pesticide solvent or inert ingredient
• Additive in adhesives
• Solvent in the manufacture of pharmaceuticals, veterinary drugs, and natural health products
• Carrier for biocides; to analyze vegetable matter, dehydrate biological samples prior to slide preparation, and isolate DNA elements
• Byproduct in the manufacture of polyethylene terephthalate (PET) plastic

However, 1,4-dioxane’s presence is not confined to industrial settings. It has been detected as an impurity or trace contaminant in various consumer products – primarily cosmetics and detergents. But many companies have been actively working to reduce this impurity in recent years.

Exposure

The primary exposure pathways for 1,4-dioxane are inhalation, ingestion, and dermal exposure.
Occupational contact and exposure are most likely to occur at manufacturing facilities. People can
be exposed following ingestion or contact with water containing 1,4-dioxane and with cosmetics/
personal hygiene products that contain ingredients in which it may be a contaminant.

Short-term exposure may cause eye, nose, and throat irritation; large quantity short-term exposure may lead to kidney and liver damage. Acute exposure to large amounts of 1,4-dioxane has been associated with adverse nervous system effects and can result in death.

Chronic exposure has shown liver and kidney damage in animals. Laboratory animal studies have also shown that oral exposure over a lifetime causes cancer, while skin exposure can also increase the cancer-causing properties of other chemicals.

Health and Environmental Concerns

Due to its high solubility in water and mobility in soils, one concern associated with 1,4-dioxane is its potential to be a contaminant in groundwater and drinking water. The compound has been identified in water supplies in various regions, leading to worries about its potential effects on public health. Prolonged exposure to elevated levels of 1,4-dioxane in drinking water may pose health risks – making it a subject of close scrutiny by regulatory agencies worldwide. USEPA has set guidelines for acceptable levels in drinking water to ensure public safety.

Regulatory agencies and environmental organizations – such as USEPA, the Occupational Safety & Health Administration (OSHA), and the Food and Drug Administration (FDA) – closely monitor and regulate the levels of 1,4-dioxane in water supplies; work environments; and food, cosmetics, and household products to ensure public safety. In order to limit the inadvertent release of this chemical into the environment, it’s important for industries to implement proper waste disposal practices – including proper wastewater treatment and containment measures to prevent its migration into groundwater.

The Environmental Working Group, the Centers for Disease Control, and the FDA emphasize the importance of raising awareness about 1,4-dioxane and advocating for responsible manufacturing practices. By encouraging the reduction or elimination of this compound in industrial processes, companies can contribute to a healthier and more sustainable environment.

The EPA, OSHA, and other state environmental agencies can also encourage limiting the use of this compound by enforcing more stringent actionable levels in air, water, and soil. For example, USEPA performed a Risk Evaluation in 2020 and drafted a supplement in July 2023 as part of the amended Toxic Substances Control Act (TSCA).

Consumer Awareness and Product Choices

Consumers can also play a crucial role in mitigating the impact of 1,4-dioxane. By being
informed about product ingredients and choosing items with lower or no levels of this compound,
individuals can make choices that align with their health and environmental values. Many
companies are now recognizing the importance of transparency in labeling and are working to
reduce or eliminate 1,4-dioxane from their products.

Treatment Technologies

Since being identified as an emerging contaminant of concern, several technologies have been utilized to remediate 1,4-dioxane with varying results. The removal of 1,4-dioxane by conventional water and wastewater treatment plants has proven to be ineffective due to its unique physicochemical properties. 1,4-dioxane dissolves completely and does not evaporate readily, making it difficult to remove from water.

Wastewater and drinking water treatment plants across the U.S. have needed to implement new techniques to meet the increasingly strict standards as new information about the effects of this compound are discovered. Common treatment technologies include advanced oxidation processes (AOPs) and bioremediation. In situ and ex situ bioremediation processes are being explored as more cost-effective, but time-consuming, remediation techniques.

Ongoing Research and Future Outlook

As the scientific community continues to study 1,4-dioxane, ongoing research aims to deepen our understanding of its behavior in different environments and its potential long-term effects. This knowledge will be instrumental in shaping regulations and industry practices to minimize the risks associated with this compound.

In conclusion, while 1,4-dioxane has widespread industrial applications, its presence in consumer products and potential impact on water supplies have raised valid concerns. Regulatory measures, responsible manufacturing practices, and informed consumer choices are essential in addressing these concerns and working towards a safer, healthier future.

How HETI Can Help

HETI’s staff of environmental scientists, geologists, industrial hygienists and remediation professionals have extensive experience in evaluating sites for potential 1,4-dioxane contamination. We coordinate/conduct soil and groundwater sampling and assess specific needs to bring sites to federal/state regulatory compliance – working with our clients in the development of various remedial approaches. Whatever the issue, HETI is here to help.