deflated between shifts strongly recommended if blasting operations are ongoing nearby All noise generating activities must be stopped while installing the headcover and while working under the headcover The headcover to be used must be the correct size for the raise The diameter range that is suitable for the installation of the headcover is from the rated diameter down to two feet less than the rated diameter Under no circumstance is the headcover to be used in a openings that are larger than the rated diameter of the headcover Procedure 1 Check scale and clear site area The area around the top of the raise and all access ways to the raise must be well scaled and blown clean The brow area around the raise breakthrough must be well scaled and ground support installed as required All remaining cuttings and loose rock must be removed from the breakthrough area 2 Place lighting at the bottom of raise if possible Adequate to create good visibility for all further work to be performed 3 Determine the lifting method to be used Using a tugger winch from the top of the raise or an access point in the raise Using a drilled hole from the breakthrough area and a cable passed through it This hole must be drilled at a 45 degree angle to the horizontal and on azimuth that will intersect the center line of the raise Depending on the circumstance the drilled hole will intersect the raise at least 60 feet up it If passing a cable through a drilled hole it must be at least inch in diameter or larger to protect from abrasion at the intersection of the drilled hole and the raise 4 Lower the cable to the raise bottom Lower an extra 30 feet of cable 5 Using a long hook retrieve the cable from under the raise Do not enter the area under the raise 6 Move the inflatable headcover into position near to the bottom of the raise Not under the raise Removing all ropes and shipping binding 7 Attach a 50 foot one inch air line to the headcover 8 Connect the lifting cable to the lifting attachment on the inflatable headcover Ensure that the lifting straps will not foul when lifting commences 9 Lift the bulkhead into place in the raise As per drawing Care must be taken not to damage the headcover on screen or any other sharp edges The bulkhead must be installed a suitable distance up the raise to allow the headcover to slide while absorbing an impact 10 Connect the regulator to the mine air and to the air line on the headcover 11 Inflate the headcover The regulator pressure gauge must indicate 1 psimin ROCVENT INC MINE TUNNEL VENTILATION 36 wwwrocventcom