Toxic Substance/Air Monitoring Services (Singapore)
Institute of Ergonomics and Hygiene (IEH) work with specialist laboratories to provide premier industrial/occupational hygiene sampling and monitoring for a safer working environment.
Requirement for Monitoring
Under Singapore WSH (General Provisions) Regulations 39, regular monitoring must be carried out if your workplace uses or generates toxic substances.
Frequency of Air Monitoring
The frequency of air monitoring depends on the exposure level:
| Exposure Level | Frequency of Air Monitoring |
|---|---|
| <10% of the PEL | Once every 3 years. A re-assessment should be carried out earlier if there is any change in the process. |
| 10% – 50% of the PEL | At least once a year |
| > 50% – 100% of the PEL | At least once every 6 months |
| > PEL | At least once every 3 months, until the exposure is reduced to below the PEL by appropriate control measures. |
Who can conduct the work?
Toxic substances monitoring must be done by competent person who have completed the WSQ course on ” Measure and Assess the Risk due to Hazardous Substances”. Samples should be collected based on validated method and analyzed by an accredited laboratory.
How many samples are required ?
Competent Person will study the workplace and its operations in order to classify workers into Similar Exposure Groups (SEGs). Sample size should be at least 3-4 samples from each SEGs or 25%-50% for SEGs of 10 or more employee.
How long is the sampling/monitoring ?
A minimum of 6 hours of sampling is required to evaluate exposure over a full 8-hour shift, or 8 hours of sampling for a full 12-hour shift. However, this is only applicable to work process with small concentration variations. Otherwise, a full shift sampling is required.
Will the employees’ task and operations be affected ?
Personal sampling equipment are designed in mind to reduce interference to the work.
What toxic substances that are required to be monitored ?
All chemicals used in the workplace that is listed with Permissible Exposure Levels values (refer to here) under the First Schedule of the WSH (General Provisions) Regulations should be monitored. Occupations with the highest expected exposure shall be monitored first.
What happen if full-shift sampling is not possible ?
If it is not possible to conduct a full-shift sampling, a series of “grab” or “spot” samples can be taken randomly throughout the workshift using detector-tubes or other appropriate instruments. The acceptable number of samples is 4 to 7.
Why choose Institute of Ergonomics and Hygiene ?
Simply put, we do this well. Our consultant will support you to develop the sampling strategy for you, helping you to decide the number of personal and area samples required to provide representative results. After monitoring, we do not stop there, we will provide recommendations and follow through to support the workplace with exposure control measures.