Laserfiche WebLink
Site Specific Health, Safety and Environmental Plan <br /> 18 <br /> <br />Task <br />Monitoring <br />Instrument <br />Monitoring <br />Frequency <br />Action Levels 1 Required Action <br />Usually performed <br />during intrusive <br />work activities <br />where oxygen <br />deficient <br />atmospheres or <br />toxic gases may be <br />encountered (e.g., <br />sewers, excavations, <br />and other confined <br />spaces, and around <br />operating <br />equipment). <br />LEL/O2/H2S/ <br />CO Meter (or <br />similar <br />combination <br />as needed) <br /> <br /> <br />Monitor whenever <br />intrusive activities <br />are being performed <br />or when working in <br />excavations or other <br />low-lying areas. <br />NOTE: Take O2 <br />readings first. If they <br />are not within <br />acceptable ranges <br />the measurements <br />for LEL, H2S and CO <br />will not be accurate. <br /> <br /> <br />O2 ~ 20.9% <br />LEL < 10% <br />H2S < 1 ppm <br />CO < 25 ppm <br /> <br />Acceptable conditions; continue <br />work. <br />NOTE: Still need to be cautious if <br />LEL concentrations are > 0 but less <br />than 10% as some type of <br />flammable chemical is present. <br />Potential for such chemicals to be <br />toxic at low concentrations. <br />Contact HSE Management for <br />assistance in these circumstances. <br />O2 < 19.5% or > <br />22% <br /> <br />LEL > 10% <br />H2S > 1 ppm <br />CO > 25 ppm <br />Stop work; Evacuate area; <br />determine source of readings and <br />take corrective actions such as <br />installing general ventilation and <br />working upwind. <br />Contact HSE Management for <br />assistance. <br />Conducting work <br />that produces <br />airborne visible dust <br />(e.g., drilling, test <br />pitting, excavation, <br />etc.) <br />Dust Monitor <br />(respirable <br />fraction) <br />Conduct monitoring <br />when dusty <br />conditions are <br />encountered in areas <br />with potentially <br />contaminated soils. <br />Monitor in the <br />employees BZ and <br />general areas. <br />Monitor initially and <br />every 15 minutes <br />while dusty <br />conditions persist. <br />< 0.5 mg/m3 in <br />the employee’s <br />BZ <br />Continue work <br />Monitor <br />continuously <br />0.5 to 5 mg/m3 <br />in the <br />employee’s BZ <br />Upgrade to Level C respiratory <br />protection or evacuate the work <br />area until BZ concentrations are < <br />0.5 mg/m3 <br />Monitor <br />continuously <br />> 5 mg/m3 in the <br />employee’s BZ <br />or general area <br />Stop dust producing activities if <br />levels cannot be maintained < 5 <br />mg/m3. Move support zone to <br />upwind location. <br />Contact HSE Management for <br />assistance. <br />O2 – Oxygen LEL – Lower Explosive Limit H2S – Hydrogen Sulfide CO – Carbon Monoxide <br />1Five excursions above the action level in any 15 minute period or a sustained reading in excess of the action levels for five <br />minutes will trigger a response. <br />2 For example, the OSHA permissible exposure limit (PEL) for gasoline is 300 ppm, therefore the action level for upgrading to <br />Level C could be adjusted (to 1/2 of the PEL - 150 ppm) if you are certain that gasoline is the only contributor to the VOC <br />measurement. Contact HSE Management for details concerning compound-specific sampling options. <br />Note: LEL readings should be taken at the point of operation (top of drill stem, well head, etc.). PID, O2, and H2S readings <br />should be taken in the worker’s breathing zone (BZ).