Chemical Health Risk Assessment (CHRA) at the Workplace

Chemical Health Risk Assessment (CHRA) is a critical and mandated assessment that employers must undertake to manage the use, handling, storage, and transportation of chemicals hazardous to health within the workplace, as prescribed by Regulation 9 of the Occupational Safety and Health (Use and Standard of Exposure of Chemicals Hazardous to Health) Regulations 2000 (USECHH).

In accordance with these regulations, employers are strictly prohibited from commencing any activities involving chemicals hazardous to health (CHTH) without first completing a thorough chemical health risk assessment (CHRA).

Consequently, this process involves systematically identifying, evaluating, and implementing control measures to mitigate any health risks posed by these substances.

Moreover, the obligation extends beyond mere usage and encompasses all facets of chemical management, including production, processing, handling, storage, transport, removal, disposal, and treatment of CHTH within the workplace.

By conducting exhaustive assessments, employers ensure that every aspect of chemical management is scrutinized to identify potential hazards. Furthermore, by adhering to this structured approach, employers not only ensure compliance with statutory requirements but also foster a safer working environment.

What is Chemical Health Risk Assessment (CHRA)?

Chemical Health Risk Assessment (CHRA) is a systematic process aimed at identifying, evaluating, and controlling health risks associated with the use of chemicals hazardous to health (CHTH) in the workplace. It is usually serves as starting point in the larger industrial industrial hygiene management umbrella which includes chemical exposure monitoring (CEM), chemical health risk assessment .

This comprehensive evaluation encompasses the potential hazards posed by chemicals, the degree of exposure workers may face, and the effectiveness of existing control measures.

Specifically, the chemical health risk assessment (CHRA) meticulously assesses the ways in which CHTH are employed, thereby identifying associated health risks and determining the necessary control measures.

Consequently, the outcome of the assessment informs the development of strategies to effectively manage and minimize workers’ exposure to these hazardous chemicals. These strategies are tailored to the specific degree of risk inherent in various work activities, ensuring a targeted and effective approach to risk management.

You also may be interested in…

How is Chemical Health Risk Assessment (CHRA) Conducted?

The assessment is conducted in accordance with the principles outlined in the guidelines established by the Department of Occupational Safety and Health (DOSH), specifically the “Manual of Recommended Practice on Assessment of the Health Risks Arising from the Use of Chemicals Hazardous to Health at the Workplace.”

Below are the steps or methodologies taken during the assessment.

To conduct a thorough Chemical Health Risk Assessment (CHRA), we must gather detailed information on the chemicals used or released in the workplace, including their hazards, exposure levels, and recommended control measures.

This involves creating an inventory of all hazardous chemicals, obtaining layout plans and process flowcharts of work areas, and compiling records of workers at risk. Additionally, we need to collect information on the design and maintenance of control equipment, as well as records of occupational incidents and personal exposure monitoring.

Health surveillance data, training program records, and details on PPE usage and standard operating procedures also form a crucial part of the assessment.

Sources for this information include the chemical register maintained by the employer, Safety Data Sheets (SDS), and recognized hazard databases. Further data can be obtained from internal departments such as Human Resources, Maintenance, Medical, and Production.

By systematically collecting and analyzing this information, we can identify potential health risks and develop strategies to manage and mitigate these risks, ensuring a safer workplace and compliance with regulatory requirements.

Ideally, all the information should be provided prior to the actual on-site assessment as more preparation can be made properly.

To identify work units, we start by conducting a walk-through inspection to identify all individuals potentially exposed to CHTH. This includes those working directly with chemicals, near areas where chemicals are used or stored, or in confined spaces.

We then gather lists of jobs, tasks, and processes for each department or work area, identify the CHTH used or released, and interview supervisors and workers to gather practical information on work practices.

Based on this information, work units are assigned according to the criteria mentioned earlier. Similar tasks involving the same chemicals can be grouped together as a single work unit.

Identification of Hazard
Then, we start by identifying each Chemical Hazardous to Health (CHTH) used or released in each work unit. Typically, this information can be obtained from Safety Data Sheets (SDS), labels of the CHTH, or waste cards for scheduled waste. We refer to Section 2 (Hazard Identification) and Section 11 (Toxicological Information) of the SDS for hazard classification and toxicological data.

If the SDS is unavailable, hazard statements from the chemical’s label can be used, or we contact the supplier for additional information. For chemicals released due to reactions or degradation, we may need specialist advice.

Degree of Hazard
Then the degree of hazard is determined based on the hazard classification, acute toxicity, or health effects of the CHTH, considering the route of exposure. For inhalation exposure, a hazard rating (HR) scale from 1 to 5 is assigned. The HR helps prioritize hazards based on potential health effects.

For processes involving mixtures of CHTH, the mixture will be classified based on the hazard classification or LC50 data of each chemical as per Part 2.5 of the ICOP CHC. This classification applies to the mixture, not individual chemicals, and does not apply to scheduled waste.

For dermal exposure, the hazard is categorized based on the chemicals’ effects on the skin and eyes, considering properties like irritation, corrosion, sensitization, or skin absorption.

Lastly, the HR is documented and we select the highest HR for each CHTH to ensure comprehensive hazard assessment. For more detailed examples, refer to the manual.

The purpose of assessing exposure is to evaluate the potential of Chemicals Hazardous to Health (CHTH) entering the body through various routes and to determine the degree of exposure causing adverse health effects to workers in each identified work unit.

The exposure will be evaluated by using either qualitative or quantitative methods. The quantitative method in this manual is specifically for inhalation, while the qualitative method applies to both inhalation and dermal routes.

Additionally, other contributing factors should be considered. If significant, the findings are recorded in Forms A and D and suggest appropriate actions.

To evaluate exposure to CHTH during normal operations, we review work procedures, observe various tasks performed, and interview members of the work unit. Important considerations in assessing workplace exposure include:

Degree of Exposure

  1. Who is exposed
  2. How and under what circumstances exposure occurs
  3. Possible routes of exposure
  4. Frequency of exposure
  5. Duration of exposure
  6. Intensity or magnitude of exposure


Other Factors

  1. Existing control measures
  2. Training and information provided to workers
  3. Monitoring of exposure
  4. Medical surveillance


We also consider the possibility of abnormal exposure, such as spillage, leaks, accidental entry into the body (e.g., through injection), increased workload, and malfunctioning of control equipment.

Special consideration may be required for susceptible groups of workers or individuals who may be at increased risk, such as pregnant women, individuals with medical conditions like bronchitis or asthma, untrained or inexperienced workers, and smokers who may be at higher risk of additive or synergistic effects.

The level of risk for inhalation exposure is determined using a risk rating (RR), which is calculated based on the hazard rating (HR) and exposure rating (ER). Chapters 4 and 5 describe the steps to determine the HR and the procedures to estimate the ER, respectively. The risk rating is determined using the following equation:

RR=HR×ER

Where:

  • RR is the risk rating (ranging from 1 to 25), indicating the likelihood of injury or illness.
  • HR is the hazard rating (ranging from 1 to 5), indicating the severity of adverse effects.
  • ER is the exposure rating (ranging from 1 to 5), indicating the chance of overexposure to the CHTH.
  • Use the equation above or refer to Table 16 to determine the RR.
table 16 of chemical health risk assessment (chra) manual

Control measures are implemented to prevent or minimize risks, specifically those associated with the use of Chemicals Hazardous to Health (CHTH).

There is a range of applicable chemical risk control measures that can typically be exercised simultaneously in the workplace.

Assessing the adequacy of these multiple control measures can be potentially tedious and confusing. To facilitate this assessment, the numerous controls are categorized as follows:

  • Technical Controls
  • Organizational Controls
  • Emergency Response Preparedness

We will evaluate the adequacy of the existing control measures, particularly the Technical Controls, as this assessment will determine further actions required to control exposure. It should be noted that the applicable control measures implemented by the employer must conform to the regulatory requirements of the USECHH Regulations.

The assessment is concluded by indicating the level of risk and the adequacy of existing control measures. Based on the findings, the assessor identifies the necessary actions to control or minimize exposure to CHTH.

An action priority (AP) is assigned to prioritize the actions to be taken by the employer based on the assessment conclusions.

The employer must establish an action plan to implement these recommended actions, prioritizing control measures according to the assigned action priority. The assessment conclusion can be categorized as follows:

  • High Risk and Adequately Controlled
  • High Risk and Inadequately Controlled
  • Moderate Risk and Adequately Controlled
  • Moderate Risk and Inadequately Controlled
  • Low Risk and Adequately Controlled
  • Low Risk and Inadequately Controlled

The assessment conclusion helps prioritize the actions required to control exposure to CHTH.

Based on the findings of the assessment, we will identify and recommend the following actions for the employer:

1. Control Measures and Procedures

  • Determine and recommend measures and procedures to control exposure to CHTH.
  • Emphasize technical controls as primary measures, complemented by organizational controls.
  • Ensure recommendations are specific, referring to industry guidelines, SDS, or other references where available (e.g., specifying the type of gloves needed).

2. Accidental Emission Control

  • Identify and recommend measures, procedures, and equipment to control accidental emissions of CHTH due to leaks, spills, or equipment failures.
  • Address inadequacies in existing measures and suggest improvements.

3. Exposure Monitoring Program

  • Assess the necessity of an exposure monitoring program for each work unit.
  • Consider factors such as inhalation exposure, likelihood of airborne chemicals, availability of PEL or OEL, and validated sampling and analysis methods.
  • Recommend specific parameters and associated exposure limits for air and biological monitoring.
  • Suggest follow-up actions, including the frequency of monitoring and reviewing control measures if exposure exceeds limits.

4. Medical Surveillance Program

  • Determine the necessity of a medical surveillance program for each work unit.
  • Consider the availability of valid techniques to detect disease or health conditions related to CHTH exposure.
  • Recommend follow-up actions if medical surveillance shows abnormal results, including reviewing existing control measures.

5. Training and Retraining

  • Recommend further training and retraining for work units handling or exposed to CHTH.
  • Identify gaps in existing training programs and suggest improvements (e.g., including worker risk communication or emergency procedures).

We will assign an action priority to each identified action. The employer should use these priorities to prepare an action plan for implementing the identified control measures. There are three levels of action priority based on the risk rating:

  • Action Priority 1 (AP-1) – Immediate action required where the risk rating (RR) is at or above 15 (RR ≥ 15) and control measures are inadequate, or where the hazard rating (HR) or exposure rating (ER) could not be determined.
  • Action Priority 2 (AP-2) – Action required where the RR is less than 15 (RR < 15) and control measures are inadequate.
  • Action Priority 3 (AP-3) – Maintain existing control measures where they are adequate, irrespective of the RR.

On the assessment day, after completing the assessment, we will debrief the client on all activities carried out. This includes the number of personnel involved, the number of work units assessed (compared to the initial information), and the number of chemicals assessed (or discovered during the assessment) and etc.

The first draft report will be completed within 30 working days. This will be followed by a presentation to the stakeholders of the assessment.

Upon agreement of the final version, a soft copy of the final report will be emailed to the client, and a hard copy will be couriered for their records and any further action as needed.

an image of a chemical health risk assessment is being carried out
An illustration of a chemical health risk assessment being conducted.

What are Included in the CHRA Report?

The chemical health risk assessment (CHRA) report will be divided into several main sections, each containing core elements essential to the assessment as per outlined by Chapter 11 – Report Writing of the manual. While the layout of the report may vary slightly between consultants and practitioners, this variation can be attributed to factors such as personal preferences, industry-specific best practices, and client requirements.

The front page of the report should serve as the title page and contain the following information:

  1. The title of the report, e.g., “CHEMICAL HEALTH RISK ASSESSMENT REPORT“
  2. Assigned report reference number, including assessor registration number, year of assessment, and serial number. Example: “Report Reference Number: HQ/17/ASS/00/00002-2017/001”
  3. Date of submission to the employer
  4. Assessor’s Name and Competency Registration Number
  5. Company’s Name, Registration of Company Number (ROC), and DOSH Registration Number (where applicable)
  6. Premise address where CHRA is conducted

The executive summary should provide a brief overview of the CHRA conducted, including the location and date of the assessment, the main objective, the key activities such as the work units selected and the total number of chemicals assessed, a summary of the findings including the total level of risk and action priorities, and the main recommendations to the employer.

The introduction provides the necessary background information to make the rest of the report easily understandable, setting the context and providing sufficient background details. It includes an introduction to the company and work site, the objectives and scope of the assessment, and a summary of previous assessments and findings if applicable.

Introduction to the Company and Work Site
This section introduces the company’s operations where the assessment was conducted.

Objective and Scope of Assessment
Describe the objectives of the assessment, specifically referring to the intent of the CHRA, such as reassessing the effectiveness of newly implemented control measures. State the scope of the assessment, including any boundaries or limitations. If the assessment is a reassessment due to significant changes or new/improved control measures, detail these changes.

Summary of Previous Assessment and Findings
If a previous assessment was conducted, include a brief summary of the findings and recommendations. If a previous assessment was done but the report is not accessible, the assessor should note this in the report.

This section describes the processes carried out at the workplace, including process flow charts or descriptions to visually explain the processes. It indicates which processes have potential exposures to CHTH and are included in the assessment scope.

Additionally, it explains how the work units were selected and categorized as similar exposure groups, detailing routine and non-routine work patterns, shift patterns, job rotation, and the category and number of workers involved, if applicable.

This section of the report describes the assessment methodology used. If the methodology is based on the established manual, it briefly explains how it was applied in the assessment.

For other assessment methods, it provides details of the methodology and describes the procedures involved based on the adopted approach.

This section correlates the findings on the level of risk and adequacy of existing control measures for each assessed work unit. The findings are best presented through labeled tables and graphs where feasible, organized by work units against the level of risk and control measure adequacy.

It highlights significant results, describes the results presented in the tables, and mentions the key findings that will be discussed in the discussion section.

This section discusses all factors that may contribute to the significant risks of the work unit mentioned in the findings section. It relates these factors to the level of risk and the adequacy of control measures. The discussion includes the adequacy and effectiveness of any implemented control measures, such as substitution, elimination, or installation of local exhaust ventilation (LEV).

It addresses positive or negative observations on work practices, procedures, and control measures that may influence the assessment results. If there are any worker health feedbacks, it explores any association with their exposure at the work unit.

This section outlines areas for improvement in controlling health risks from the assessed chemicals and compliance with regulatory requirements. The assessor should make recommendations to the employer that are Specific, Measurable, Achievable, Realistic, and Time-Bound (SMART).

The recommendations should be based on the interpretation of the findings and include the following proposed actions:

  1. Technical control measures
  2. Organizational controls with an emphasis on training and retraining
  3. Emergency response preparedness
  4. Exposure monitoring
  5. Medical surveillance

Lastly, all references will be listed in the References section while the appendices shall contain:

  1. Forms A, B, C, and D
  2. Layout plan and the location of the workers selected for assessment (where applicable)
  3. Process flowchart
  4. Valid assessor’s competency slip
  5. Other relevant information (such as laboratory analytical results)

What are the Benefits of CHRA to the Organization

Conducting a Chemical Health Risk Assessment (CHRA) at the workplace offers numerous advantages. It has been reported that comprehensive CHRA can significantly enhance workplace safety and health standards, leading to better compliance with regulations and improved overall productivity. Among the benefits of conducting CHRA at the workplace are:

1. Enhanced Workplace Safety
Identifying and mitigating chemical hazards by means of chemical health risk assessment (CHRA) helps prevent workplace accidents and health issues, ensuring a safer environment for employees.

2. Regulatory Compliance
Conducting chemical health risk assessment (CHRA) ensures that the organization complies with occupational safety and health regulations, avoiding potential legal penalties and enhancing the company’s reputation.

3. Improved Risk Management
Systematic assessment and management of chemical hazards enable the organization to prioritize and implement effective control measures, reducing risks associated with chemical exposures.

4. Health Protection for Employees
Chemical health risk assessment (CHRA) helps in monitoring and controlling workers’ exposure to hazardous chemicals, thereby protecting their health and well-being.

5. Cost Savings
By preventing chemical-related incidents and illnesses, the organization can save on medical costs, compensation claims, and potential downtime.

6. Increased Employee Morale and Productivity
A safer work environment boosts employee morale and productivity, as workers feel valued and protected.

7. Proactive Approach to Safety
Recommended actions from the chemical health risk assessment (CHRA) report may promote a proactive approach to chemical safety, encouraging continuous improvement and fostering a culture of safety within the organization.

CHRA Frequently Asked Questions (FAQ)

A work unit is a group of workers who perform similar tasks and are exposed to the same chemicals hazardous to health (CHTH). This grouping allows for a more efficient assessment of health risks associated with chemical exposure in the workplace.

There are two basic requirements for forming a work unit:

  • Workers in the work unit must perform similar tasks, meaning they have similar potential for exposure to hazardous chemicals.
  • Workers must use or be exposed to the same CHTH, indicating potential exposure to the same hazard.

The work unit definition will only apply to the routine entry of persons into the workplace. These are applicable to workers and in-house contract workers.

Routine work refers to regular, scheduled activities that occur consistently within the workplace. This includes tasks such as production, maintenance, laboratory work, and housekeeping. These activities are part of the day-to-day operations and are performed by workers and in-house contract workers.

Non-routine work, on the other hand, encompasses periodic but intensive tasks that do not occur on a regular schedule. Examples include periodic maintenance, repairs, delivery, administrative work, management tasks, safety inspections, and internal audits.

Non-routine entries also cover sporadic visits by vendors, contractors, customers, external auditors, and inspectors. These activities are not part of the regular workflow and typically require special attention to safety measures.

An assessment is not required for non-routine entry and general control measures may be applied at the discretion of the employer.

As a general guide, where respiratory protection and eye protection is required for the workers in the work area, the visitor shall also wear respiratory and eye protection that affords a similar level of protection.

If direct skin contact is not expected, then the provision of skin protection is at the discretion of the employer.

References

  1. Occupational Safety and Health Act (OSHA) 1994.
  2. Occupational Safety and Health (Use and Standards of Exposure of Chemicals Hazardous to Health) Regulations, 2000.
  3. Occupational Safety and Health (Classification, Labelling and Safety Data Sheet of Hazardous Chemicals) Regulations, 2013.
  4. A Manual of Recommended Practice on Assessment of the Health Risks Arising from the Use of Chemicals Hazardous to Health at the Workplace, Third Edition 2018.