RCS (Respirable Crystalline Silica) is found at varying levels in all dust, especially within the Mining, Quarrying, Construction, Agriculture,Cement, Crushing and Earthmoving Industries.
However, compliance is not just about RCS. To provide the required protection one needs to also consider other types of Particulate and Fibre "nasties" that maybe within dust such as Asbestos, Nickel, Alumina, etc and TWA (Time- Weighted-Average) exposure limits are detailed in the current National Exposure Standards for Atmospheric Contaminants in the Occupational Environment [Worksafe- NOHSC: 1003(1995)
Here are some latest requirements for compliance to SafeWork Australia's Nationalised Standards for Workplace Exposure Standards for Airborne Contaminates:
- Respirable Silica (RCS): (present in all common "Dust" environments) with Australian Standards for OEL for a 12 hour shift less than 0.05 mg / M3 TWA with an arrestance of all particulate of >0.3 micron.
- Asbestos Fibre: has been reduced to virtually zero by the International Agency for Research on Cancer (IARC) but current exposure is set to the same as for RCS (TWA 0.05 mg Fibre / M3- 12 hours shift).
- Diesel Particulate Matter (DPM): in the way of engine exhaust, has been deemed a Class 1 Carcinogenic by the IARC / World Health Organisation (WHO) and Safe Work Australia.
- For other Airborne contaminants OEL / PEL (Occupational / Personal Exposure Limits) for both gaseous and particulate exposure then one needs to consult the Safework- NOSCH 1003- 1995 Exposure to Airborne Particulate.
Also one needs to consider:
- Sampling / 30 year Record Keeping: under the current Safe Work Australia Regulative Guidance on the Interpretation of Workplace Exposure Standards for Airborne Contaminates- April 2013, workplaces are to ensure that they sample each worker and maintain records of sampling for 30 years. This means that if sampling is not completed, if records are not maintained then respective employers will risk liability if Health issues arise - irrespective if the worker varies his workplace / employer over- time.
- PBCU (Person or Business Conducting an Undertaking): Under the Safe Work WHS Act those in the Chain of Accountable for ensuring Workers Safety and Health also now include, Suppliers, Importers, OEM's, Designers, Installers, etc and that severe penalties under Category 1,2 and 3 apply (see page 35- 40).
To achieve compliance then HVAC / PFP Filter Elements for both External Air and Recirculation Air supply to / within Operators Cabin must:
- Remove Respirable Dust / Particulate / Fibre sized between PM1 and PM10. Note that other Particulate such as Inspirable (upto 20.0 micron) and Inhalable (above 20.0 micron) are also to be removed by filtration as these cause other health issues.
- HEPA grade Filter Elements MUST be utilised. This provide extraction / filtration of all particles sizes >0.3 micron @ 99.995 arrestance efficiency and so will comply to all particulate size extraction.
For more information or assistance, please contact us at LSM Technologies via email or contact us.