1.1 How is Air Monitoring conducted?

Recruiting the services of a specialist in the field such as a qualified occupational hygienist is highly recommended to carry out air monitoring effectively because it involves complicated tasks such as analysing the results of the air monitoring and deciding whether or not it is complying with the exposure standards. Air monitoring should ideally be conducted on a normal working day when all the processing activities are happening. It usually takes 1 day to complete an air monitoring program however if there is a range of processes that need examining, additional time may be required to complete the monitoring program.

1.2 Consultant at work

Exposure measurements should be random and representative of actual worker exposure. A consultant will devise an air monitoring strategy and will finalise the number of workers, the areas and the lapse of time to be assessed. A sampling device such as a special meter or a collection tube should be fastened to the apparel of the worker to conduct “personal monitoring” which is within the breathing zone of the worker. Static samples taken at fixed locations in the workplace do not provide accurate exposure information of a worker. They should only be used to examine the efficacy of process hazard control measures. To be able to detect certain leaks or sources that can potentially increase workers exposure above the exposure standard in advance, fixed continuous monitors can be used. It is always advisable to get the samples analysed by laboratories accredited to National Association of Testing Authorities  (NATA) to perform such analysis. To check the list of accredited laboratories, please visit the website for the National Association of Australian Authorities (NATA).

Figure 1: Key steps in assessing compliance

1.3 Assessing compliance

Application of exposure controls is the primary step to attain compliance with the exposure standard. Exposure monitoring can only proceed after the exposure controls have been installed. When the exposure standard is suspected to have been surpassed and the efficacy of the controls are being questioned, air monitoring should be conducted to ensure legal compliance is still being met.

1.4 Tools and methods to assess exposure

Variables such as the source of chemical generation, rates of airflow ventilation, systems of extractions and limitations of the mathematical model to be used for air contaminant level estimation should be considered.

The functioning of the ventilation systems can be investigated by measuring the air flow and using smoke tubes while dust lamps can identity invisible particles cloud in normal lighting conditions.

Figure 2: Visualising air movement using smoke in a fume cupboard

1.5 Air Monitoring Report

A full written report should be provided and should be inclusive of the following information:

• The objective and background of the air monitoring program
• The processes investigated including details on the work patterns, workers and hazards
• The effectiveness of the control measures in the workplace
• Diagrams, illustrations and pictures where required
• The methods of sampling employed and the types of measurement recorded
• The points where samples were collected, the methods the samples were studied and the test results achieved
• Interpretation of the test results and their compliance with the exposure standard
• A concluding opinion on the results with respect to the exposure standard as to whether it is still within the standard or the standard has been exceeded
• Another opinion on the impact of the health and safety of the workers
• Advice on contemporary business practices and effective control measures
• Recommendations for improvement of the controls at the workplace

1.6 Monitoring the Health of workers

Sometimes, health monitoring may be crucial to determine risks for workers who are exposed to hazardous substances. This may include biological monitoring that investigates all pathways of exposure and is not limited to just inhalation of airborne contaminants.

Find out how Anitech can help your business with Measurement of Hazardous Substances.

Read Related Articles:

• How to Measure Hazardous Substances
• Adjusting Exposure Standards for Prolonged Work Shifts when Measuring Hazardous Substances