Report – Coal – Exposure to irrespirable atmospheres – September 2025 to April 2026

This report provides the findings of an assessment program at underground coal mines focussing on the ventilation control plan

Sector	Coal – underground
Principal control plan	Ventilation control plan
Material unwanted event	Exposure to irrespirable atmospheres
Topic	Coal-UG-exposure to irrespirable atmospheres

Operation type assessed

Operation type	Number of mines assessed
Underground	17
Total	17

Criteria assessed

Critical control	Criteria
Mine Design to manage contaminant generation and/or interaction with contaminants to within safe limits	Has the mine executed their design to minimise generation and interaction with irrespirable conditions, including: Blasting to design Underground areas executed to design Ventilation (type, volume and layout) executed to design
Workers restricted / removed from areas with irrespirable atmospheres	Are personnel aware of the techniques to restrict or remove personnel from areas with irrespirable atmospheres, including: Blast exclusion zones Underground exclusion zones Application of remote mining Ventilation control devices TARPs for the withdrawal of personnel Is there evidence these are being implemented effectively on site? Can personnel on site correctly identify irrespirable or unsafe atmospheric conditions?
Ventilation flow rates controlled to remove or minimise contaminants	Verify ventilation flowrates throughout the mine. Does it match the designed flowrates?
Pre-drainage and gas drainage (irrespirable gas reduction)	Is gas drainage being conducted as per design?

Findings with issues identified – underground mines

Critical control	Criteria	Findings of concern	Findings of contravention	Total findings with issues
Mine Design to manage contaminant generation and/or interaction with contaminants to within safe limits	Has the mine executed their design to minimise generation and interaction with irrespirable conditions, including: Blasting to design Underground areas executed to design Ventilation (type, volume and layout) executed to design	1	0	1
Workers restricted / removed from areas with irrespirable atmospheres	Are personnel aware of the techniques to restrict or remove personnel from areas with irrespirable atmospheres, including: Blast exclusion zones Underground exclusion zone Application of remote mining Ventilation control devices TARPs for the withdrawal of personnel Is there evidence these are being implemented effectively on site?	1	0	1
	Can personnel on site correctly identify irrespirable or unsafe atmospheric conditions?	1	0	1
Ventilation flow rates controlled to remove or minimise contaminants	Verify ventilation flowrates throughout the mine. Does it match the designed flowrates?	1	0	1
Pre-drainage and gas drainage (irrespirable gas reduction)	Is gas drainage being conducted as per design?	0	0	0
Total program findings with issues		4	0	4
Other topic findings – not related to Ventilation CP irrespirable atmospheres		9	4	13

Compliance notice type issued during the program

Notice type	Notices	Percentage of all notices issued
WHS(MPS)A s23 notice of concerns	11	73%
WHSA s191 improvement notice	4	27%
WHSA s195 prohibition notice	0	0%
Total	15	100%

A total of 15 compliance notices were issued to 8 UG coal mines

Note: This data represents all notices issued during the program and may include notices other than Ventilation CP-irrespirable atmosphere topics.

Recommendations

Operators of underground coal mines should review their site principal ventilation control plan and the critical controls assessed for the topic of exposure to irrespirable atmospheres.

Critical control	Criteria	Recommendations to industry
Mine Design to manage contaminant generation and/or interaction with contaminants to within safe limits	Has the mine executed their design to minimise generation and interaction with irrespirable conditions, including: Blasting to design Underground areas executed to design Ventilation (type, volume and layout) executed to design	Ensure blast generated atmospheres are effectively removed from working areas Ensure temporary ventilation devices (brattice bags, air fans) are installed, inspected regularly for effectiveness and replaced with permanent ventilation devices as soon as practicable
Workers restricted / removed from areas with irrespirable atmospheres	Are personnel aware of the techniques to restrict or remove personnel from areas with irrespirable atmospheres, including: Blast exclusion zones Underground exclusion zones Application of remote mining Ventilation control devices TARPs for the withdrawal of personnel Is there evidence these are being implemented effectively on site?	Ensure workers entering into return roadways are notified by signage and information for potential for blasting generated atmospheres being present Ensure workers are notified of exclusion zones and modifications to the exclusion zones Ensure workers and supervisors are trained and verified competent in TARP withdrawal conditions for contaminant gasses. Consider the type of gas monitoring in use and determining the time weighted average (TWA) exposure levels for workers
	Can personnel on site correctly identify irrespirable or unsafe atmospheric conditions?	Ensure workers and supervisors are trained and verified competent the in the site ventilation control plan for identification and management of irrespirable or unsafe atmospheric conditions
Ventilation flow rates controlled to remove or minimise contaminants	Verify ventilation flowrates throughout the mine. Does it match the designed flowrates?	Ensure ventilation flow rates are monitored by regular inspection and reporting systems to ensure flow rates align within the ventilation design range
Pre-drainage and gas drainage (irrespirable gas reduction)	Is gas drainage being conducted as per design?	Ensure gas drainage activities are designed and monitored for effective in-situ gas reduction strategies Ensure gas drainage stand pipes are installed and monitored to reduce potential for gas leakage into the roadway ventilation system