Factory safety teams often have an up-to-date chemical register and a folder of Safety Data Sheets (SDS), yet still struggle to explain whether worker exposure is controlled. The missing link may be a task-specific assessment of how chemicals are used, and where relevant, a Chemical Health Risk Assessment (CHRA).
Three chemical management concepts that must not be confused
Safety Data Sheet (SDS)
An SDS provides hazard information from the chemical supplier, including identification, classification, exposure controls, handling and emergency guidance. A useful SDS does not establish what concentration an individual worker inhales in your particular process.
CLASS Regulations 2013
The Malaysian CLASS Regulations regulate supplier responsibilities for classification, packaging, labelling, SDS and related chemical inventory information. Suppliers must provide hazard communication in accordance with the applicable regulations.
USECHH Regulations 2000 and CHRA
The USECHH Regulations concern workplace use and exposure to chemicals hazardous to health. They address assessment of health risks and the controls, instruction, monitoring and health surveillance that may be relevant in specific circumstances. A CHRA is a specialised assessment under this framework; a generic HIRARC worksheet is not automatically equivalent to one conducted in accordance with USECHH requirements.
What should employers examine before a CHRA?
- Identify every relevant chemical and the tasks in which it is used.
- Confirm current SDS and hazardous ingredients where applicable.
- Review quantity, frequency, duration and route of exposure.
- Inspect engineering controls such as local exhaust ventilation and enclosure.
- Identify who may be exposed, including cleaning and maintenance workers.
- Check previous exposure measurements, incidents and worker feedback.
Worked example: solvent cleaning at a workbench
The SDS identifies potential inhalation and skin hazards. The site uses solvent for brief cleaning tasks, but daily frequency has increased after a production change. Management should reassess the exposure scenario, ventilation effectiveness, handling procedure and chemical health risk assessment obligations rather than assuming the original SDS resolves the new risk.
Why PPE alone is insufficient
Gloves, goggles and respirators can have a place in a control strategy, but selection depends on the substance, concentration, task and approved protection level. Where practicable, reduce exposure by substitution, enclosure, ventilation or process modification. Verify controls in operation and review when circumstances change.
Competence and management follow-through
Workers should know how to obtain current hazard information and apply approved handling controls. Managers must ensure resulting assessment recommendations are translated into funded actions with owners, dates and verification. Specialist CHRA work should be performed by appropriately qualified or registered personnel where required by current rules.
Training and support
See Chemical Management (USECHH Awareness) and Safe Chemical Handling programmes for practical worker awareness. A training course is not a replacement for the statutory CHRA service. Discuss your needs and determine the appropriate specialist scope.
Official references
DOSH Chemical Management: USECHH Regulations 2000, CLASS Regulations 2013 and CHRA guidance. Consult current regulatory texts and approved competency arrangements.



