1. PURPOSE This prcedure is designed t prevent flash fires r explsins frm unintentinal ignitin f an explsive mixture f flammable gas and air. 2. SCOPE This prcedure applies t Ontari Mining Operatins, where drilling is cnducted and the pssibility f encuntering flammable gas may ccur. 3. INTRODUCTION Flammable gas is nrmally encuntered during diamnd drilling, shaft dewatering and less frequently encuntered during develpment and prductin drilling. In the Sudbury mining area, many mre methane encunters appear t ccur when diamnd drilling in quartzites (a metasediment) than ther rck masses. Methane gas is the mst cmmn gas encuntered which is why gas detectin equipment is calibrated t measure methane. It is imprtant t nte that methane is much lighter than air and therefre tends t travel upward alng the back f a drift if there is nt enugh airflw fr mixing f gases and dilutin. Methane will burn r explde in cncentratins frm 5 15% vlume in atmsphere in the presence f a surce f ignitin. The lwest cncentratin f a gas r a vapur in air that is capable f prducing a flash f fire in presence f an ignitin surce is knwn as the lwer explsive limit (LEL). At a cncentratin lwer than the LEL, gas mixtures are "t lean" t burn. Methane gas has an LEL f 5% vlume. 4. LEGAL AND OTHER REQUIRMENTS 4.1 Occupatinal Health and Safety Act Occupatinal Health and Safety Act, R.S.O. 1990, c. O.1. 4.2 Mines and Mining Plants, Regulatin 854 Occupatinal Health and Safety Act - R.R.O. 1990, Reg. 854, Sectin 21(5,b) and 35. 5. DEFINITIONS Supervisr r Designate Supervisr r persn designated by the supervisr must be cmpetent and qualified thrugh knwledge, training and experience t crdinate the requirements utlined in this prcedure. Types f Flammable Gas Flammable gases encuntered undergrund are usually clurless and durless. Methane, prpane, butane, ethane, hydrgen sulfide and hydrgen are examples f sme f the flammable gases that may be detected undergrund. See the identificatin f flammable gas sectin fr mre details. Page 1 f 9
Measurable Flammable Gas Cncentratin: Fr the purpse f this prcedure and fr ntificatin t the Ministry f Labur (MOL), measureable gas cncentratins are cnsidered 5% LEL (0.25% by vlume) r greater when taken 1.5 t 3 ft (0.5 t 1 m) abve the surce. Ignitin Surces: Cmmn ignitin surces are sparks frm muck hitting muck r steel, sparks frm drilling hles r tightening blts, electrical sparks frm activating equipment, smking, diesel engines and exhausts, static electricity frm air blwing thrugh ductwrk r lading ANFO, and blasting. Fire Hazard Area: N smking, nn-flammable initiatin f blasting, n burning r pen flames. 6. IDENTIFICATION OF FLAMMABLE GAS 6.1 A flw f flammable gas may be detected by any f the fllwing: Alarm frm fixed mnitr n diamnd drill (mnitr may shut dwn pwer t drill) Gas bubbling in water frm drill hle Gas bubbling in standing water Sudden heavy flw f water frm drill hle Sudden back pressure n drill, blwing cuttings and water frm hle Hissing sund frm drill hle r rck face Any flash fire/flame Presence f ther gases r drs such as hydrgen sulfide (rtten egg dr), sulfur dixide (sharp & pungent dr) and hydrgen (clrless & drless, psitive interference with carbn mnxide sensr). 6.2 In mines where flammable gas is knwn t ccur, wrkers wh are undergrund r diamnd drillers wh are n the surface shall be advised f the prbability f encuntering a flw f the gas; and the measures and prcedures utlined in this dcument. 7. MATERIALS AND RESOURCES 7.1 The use f calibrated gas detectrs t measure methane (CH4) cncentratins: Fixed mnitr n diamnd drill Prtable gas detectr (e.g. Drager X-am 2000 r 5000 r equivalent) 7.2 Prtable gas detectrs (e.g. Drager X-am 2000 r 5000 r equivalent) will nt perate if it has nt been bump tested within a 24 hur perid. Page 2 f 9
7.3 Prtable gas detectrs (e.g. Drager X-am 2000 r 5000 r equivalent) are set-up t measure gas cncentratins as a percent f the Lwer Explsive Limit (% LEL). 7.4 Prtable gas detectrs (e.g. Drager X-am 2000 r 5000 r equivalent) can be equipped with a CO/H 2 sensr t prevent psitive interferences frm Hydrgen (H 2 ) during methane ccurrences. 7.5 Gas cncentratins at the surce referenced in this prcedure are taken apprximately 1.5 t 3 ft (0.5 t 1 m) abve a drill hle surce and shuld be recrded in percent f the LEL (% LEL). 7.6 Percent by vlume is als included fr reference t the regulatin. 7.7 Examples: 100 % LEL is equal t 5% vlume methane. 10 % LEL is equal t 0.5 % vlume methane. 5 % LEL is equal t 0.25 % vlume methane. 7.8 Additinal readings may be taken in the wrkers breathing zne, near the back where methane can accumulate and at the flr fr ther flammable gases but shuld nt be used t define required actins. 7.9 Training in the use, care and maintenance f prtable gas detectin equipment is required fr thse measuring gas cncentratins. Training can be prvided by Learning and Develpment r Occupatinal Health. 7.10 See Appendix A (Flammable Gas Decisin Tree), Appendix B (Flammable Gas Task Analysis) and Appendix C (Flammable Gas Occurrence Frm). 8. PROCEDURE REQUIREMENTS This prcedure fllws the requirements as per sectins 21(5) and 35 f Regulatin 854/90 regarding flammable gas in undergrund wrkings and defines actins t be taken at varius cncentratins f flammable gas. 8.1 Immediate Actins When flammable gas is suspected r encuntered, the fllwing immediate actins are required: 1. Stp all wrk in the immediate area. Shut ff and de-energize equipment immediately and investigate. 2. Eliminate all surces f ignitin (including pen flames, grinding, sparks, static electricity, blasting, smking etc.). 3. Open air headers. Blw cmpressed air at the hle cllar. Nte: each shift air must be available befre drilling cmmences. 4. Ensure ventilatin fans are perating and the area is prperly ventilated. Page 3 f 9
5. Exit the affected area immediately. Erect a duble barricade with apprpriate signage (e.g. DANGER-METHANE, DANGER KEEP OUT FOUL AIR ) t prevent entry t area. 6. Ntify supervisr. 8.2 Fllw-up Actins Once immediate actins have been taken and the supervisr has been ntified, the fllwing fllwup actins are required: 1. Supervisr r designate, shall investigate the area where flammable gas is suspected r encuntered and cnfirm the presence f flammable gas with the use f a prtable gas detectr (e.g. Drager X-am 2000 r 5000 r equivalent). 2. If the gas detectr identifies flammable gas cncentratins greater than 10% LEL (0.5% by vl.) in the general wrkplace atmsphere: Retreat frm the area. Reinstall barricade and sign. Ntify Supervisr. Cntinue t allw the area t ventilate. The supervisr r designate may cntinue t measure fr flammable gas at the entrance f the wrkplace where the barricade is installed and may peridically test the general wrkplace t determine if cncentratins have been reduced t less than 10% LEL (0.5% by vl.). 3. If the gas detectr identifies flammable gas cncentratins less than 10% LEL (0.5% by vl.) in the general wrkplace atmsphere, measurements shall then be taken 1.5 t 3 feet frm the cllar f the hle r flammable gas surce. 4. If cncentratin f methane is less than 5% LEL (0.25% by vl.) at the surce: Ntify supervisr. Surce must be tested peridically thrughut the shift. Wrk can prceed. Supervisr t cmplete Flammable Gas Occurrence Frm (see Appendix C) and submit t the plant Ventilatin Supervisr/Specialist and the Safety Supervisr. 5. If the cncentratin f methane is greater than 5% LEL (0.25% by vl.) but less than 10% LEL (0.5% by vl.) at the surce, the fllwing precautins are required prir t start f wrk: Exit the area and install duble barricade with apprpriate signs Ntify supervisr. The supervisr is t prvide written instructins (ex: SSA/JHA) f required precautins. The supervisr is t cmmunicate instructins t wrker(s) each shift. Page 4 f 9
The affected area is designated a fire hazard area (remve flammable r cmbustible materials). A prtable gas detectr is t remain in area fr testing the surce prir t the start f wrk and peridically thrughut the shift (nte any further release f gas and recrd the % LEL). Supervisr t cmplete Flammable Gas Occurrence Frm (see Appendix C) and submit t the plant Ventilatin Supervisr/Specialist and the Safety Supervisr. 6. If the cncentratin f methane is greater than 10% LEL (0.5% by vl.) at the surce, the fllwing precautins apply: Exit the area and install duble barricade with apprpriate signs Ntify Supervisr Wrk cannt resume. Affected area t remain under cnditins as per Immediate Actin (Sectin 7.1). Affected area may require time r increased airflw fr cncentratins t be diluted. During day shift, cntact Ventilatin Department t verify air vlume if methane gas cncentratins d nt decrease after 2 hurs r if resumptin f wrk is required in affected area t remedy the situatin. If levels greater than 10% LEL (0.5% by vl.) ccur after day shift hurs r n weekends, keep the auxiliary ventilatin system running and guardrail the area with apprpriate signage and remain ut f area until next regular day shift. All persns ther than thse testing the air and addressing the ventilatin are t be remved frm the area. Supervisr must cmplete a Flammable Gas Occurrence Frm (Appendix C) and submit t the plant Ventilatin Supervisr/Specialist and the Safety Supervisr. 8.3 Reprting 1. If flammable gas is detected r suspected, an SAP IM must be generated. 2. When flammable gas is suspected r encuntered this shall be recrded in the drilling reprt and shift lg bk. 3. Supervisr t cmplete Flammable Gas Occurrence Frm and send a cpy t the plant Ventilatin Supervisr/Specialist and plant Safety Supervisr. 4. The plant Safety Supervisr will reprt t the Ministry f Labur (MOL): When a mine has never encuntered methane befre; r; When a hle emits mre than a 5% LEL (0.25% by vl.) fr readings taken apprximately 1.5 t 3 ft (0.5 t 1 m) abve the surce. The reprt t the MOL shall include the fllwing infrmatin: lcatin (mine, level, heading, hle, depth) type f wrk being dne (Dia. Drilling, drifting, raising, etc.) identity f wrker and supervisr (this wuld prvide leads t fllw up if nec.) Page 5 f 9
means f initial recgnitin (bubbles, smell, pressure n drill string, flames). actual reading in % vlume in air, gas type, time f reading. 9. REVISIONS This SPI shuld be reviewed as required when the referenced standards, new standards arise, r regulatry requirements change; a frmal review shall be required within three years f the revisin date. REVISION TRACKING Page 6 f 9
Appendix A Flammable Gas Decisin Tree Flammable gas is detected r suspected. Stp all wrk in the immediate area Supervisr r designate shall investigate and cnfirm the presence f flammable gas with the use f a prtable gas detectr Is the general wrkplace cncentratin > 10% LEL (0.5% by vl). N Yes Shut ff and de-energize equipment. Eliminate all surces f ignitin. Blw cmpressed air at the cllar f hle r surce. Ensure area is prperly ventilated. Erect a duble barricade with apprpriate signage. Exit the area. Ntify supervisr Retreat frm the area Reinstall barricade and signs Ntify supervisr. Cntinue t allw the area t ventilate Measure flammable gas at the entrance f the wrkplace (duble guardrail and signs). Peridically test the general wrkplace t determine if cncentratins have been reduced t < 10% LEL (0.5% by vl.). Supervisr t cmplete flammable gas ccurrence frm Cnfirm the presence f flammable gas at 1.5 t 3 feet abve the surce (cllar f hle). Is the cncentratin at the surce < 5% LEL (0.25% vl.)? Yes Ntify supervisr Prceed with wrk if area is tested peridically Wrk can prceed Supervisr t cmplete flammable gas ccurrence frm N Reprt t the MOL when a hle emits >5% LEL (0.25% vl.), at 1.5 t 3 ft (0.5 t 1 m) abve the surce. Flammable gas ccurrence frm t be submitted t the plant ventilatin specialist and safety supervisr Safety supervisr t reprt t the MOL Is the cncentratin at the surce between 5% LEL (0.25% vl.) - 10% LEL (0.5% by vl.)? N Is the cncentratin at the surce > 10% LEL (0.5% by vl.)? Yes Exit the area and install duble barricade and signs. Ntify supervisr Supervisr t prvide written instructin via SSA/JHA f required precautins Supervisr t cmmunicate instructins each shift Remve cmbustible materials. Area tested befre wrk begins, thrughut the shift and again n release f any further flw f gas Gas detectr left in area fr testing. Supervisr t cmplete flammable gas ccurrence frm Yes Wrk cannt resume Exit the area and installed duble barricade and signs Ntify Supervisr Eliminate ignitin surces & de-energized electrical equipment Cntinue t ventilate the surce and general area. All persns ther than thse testing air and addressing ventilatin t be remved frm area. Supervisr t cmplete flammable gas ccurrence frm. Page 7 f 9
Appendix B Flammable Gas Task Analysis Pssible Flammable Gas Cnditin Actins t be Taken Flammable gas is detected r suspected. Area where flammable gas is suspected r encuntered, is the general wrkplace cncentratin > 10% LEL (0.5% by vl.)? Area where flammable gas is suspected r encuntered, is the general wrkplace cncentratin < 10% LEL (0.5% by vl.)? Is the cncentratin 1.5 t 3 feet abve the surce < 5% LEL (0.25% vl.)? Is the cncentratin 1.5 t 3 feet abve the surce between 5% LEL (0.25% vl.) and 10% LEL (0.5% by vl.)? Is the cncentratin 1.5 t 3 feet abve the surce > 10% LEL (0.5% by vl.)? Shut ff and de-energize equipment. Eliminate all surces f ignitin. Blw cmpressed air at the cllar f hle r surce. Ensure area is prperly ventilated. Exit the area. Erect a duble barricade with apprpriate signage. Ntify the supervisr. Supervisr r designate shall investigate and cnfirm the presence f flammable gas with the use f a prtable gas detectr. Retreat frm the area. Re-install duble barricade and signs Ntify Supervisr Cntinue t allw the area t ventilate. Measure flammable gas at the entrance f the wrkplace Peridically test the general wrkplace t determine if cncentratins have been reduced t < 10% LEL (0.5% by vl.). Ntify Supervisr Cnfirm the presence f flammable gas at 1.5 t 3 feet abve the surce (cllar f hle). Ntify Supervisr Prceed with wrk if area is tested peridically thrughut the shift. Exit the area and install duble barricade and signs. Ntify Supervisr Supervisr t prvide written instructin and cmmunicatin t wrker(s) via SSA/JHA each shift. Remve cmbustible materials. Gas detectr left in area fr testing, surce t be tested befre wrk begins, thrughut the shift and again n release f any further flw f gas. Safety Supervisr will reprt t MOL when > 5% LEL (0.25% vl.) has been detected at 1.5 t 3 ft (0.5 t 1 m) abve the surce. Exit the area and installed duble barricade with apprpriate signs Ntify Supervisr Wrk cannt resume Eliminate ignitin surces De-energized electrical equipment Cntinue t ventilate the hle and general area. All persns ther than thse testing air and addressing ventilatin t be remved frm area. Safety Supervisr will reprt t MOL when > 5% LEL (0.25% vl.) has been detected at 1.5 t 3 ft (0.5 t 1 m) abve the surce. Page 8 f 9
Appendix C Flammable Gas Occurrence Frm Flammable Gas Occurrence Frm Date f Occurance: Reprted by: Time f Occurance: Lcatin: Supervisr: Descriptin f Wrk: Descriptin f what ccurred: Supervisr ntified Equipment shut ff Sr Specialist Vent Ntified Hle ventilated Safety Supervisr Ntified Area guarded Wrker Rep Ntified Area Clear Methane Detectr Type Fans n and area ventilated Hle N: Hle Depth: Methane at the Surce (1½-3ft frm hle) Methane in General Wrkplace Atmsphere % Methane (% LEL) Time % Methane (% LEL) Time Nte: If methane cncentratin at the surce (1.5-3 ft abve the surce) is > 10% LEL (0.5% by vl.), wrk cannt cntinue. If methane cncentratin in general wrkplace atmsphere is > 10% LEL (0.5% by vl.) retreat frm the area and cntinue t ventilate. COMMENTS: Cmpleted frm t be sent t the Ventilatin Supervisr and Safety Supervisr. Page 9 f 9