Safe maintenance industrial covers

Abstract

The Safety Manhole Industrial Cover (SMIC) is a lightweight temporary safety manhole cover with a hinged access door made with aluminium or a strong nonferrous composite used when sewerage, storm water, water maintenance or inspections are required. It is a temporary self-ventilating design manhole grate to be used whenever the manhole cover is removed when operations are in progress around the manhole. The slots allow for natural light and airflow and it allows workers below ground to see through to the persons above; and vice versa. The safety manhole cover is designed to eliminate the risk of falling from heights regulations requirement whilst works are carried out near or over sewer openings by allowing the operators to walk freely above ground without having a harness to secure themselves.

We claim: 
     
         1 . A lightweight temporary safety manhole cover comprising:
 (i) a plurality of ventilation slots in main body of the cover;   (ii) an underside bearing flat stiffening bars;   (iii) a load bearing hinged access door; and   (iv) the cover sits on top of a concrete lip of the manhole opening wherein the slots occupy a substantial portion of the cover to provide adequate ventilation and light to a worker undertaking maintenance below ground; and at least one of the slots is substantially rectangular in shape and this slot is continuous from centre to circumference of the cover,   wherein the manhole cover is substantially circular, spherical, or oval.   
     
     
         2 . The cover according to  claim 1  wherein the underside of the safety cover has three flat bars attached to a concentric flat bar ring for support. 
     
     
         3 . The cover according to any one of the  claim 2  when used for conducting maintenance below ground enabling a worker to be secured by means of a harness to be lowered down the cover. 
     
     
         4 . The cover according to  claim 3  wherein the harness is secured by a cable which is positioned in the slot which is continuous from the centre to the circumference of the cover as defined in  claim 1 . 
     
     
         5 . A lightweight temporary safety manhole cover comprising:
 (i) a plurality of ventilation slots in main body of the cover;   (ii) an underside bearing flat stiffening bars;   (iii) a load bearing hinged access door; and   (iv) the cover sits on top of a concrete lip of the manhole opening wherein the slots occupy a substantial portion of the cover to provide adequate ventilation and light to a worker undertaking maintenance below ground; and at least one of the slots is substantially rectangular in shape and this slot is continuous from centre to perimeter of the cover,   wherein the manhole cover is substantially rectangular or square.   
     
     
         6 . The cover according to  claim 5  wherein the underside of the safety cover has three flat bars attached to a concentric flat bar ring for support. 
     
     
         7 . The cover according to  claim 6  when used for conducting maintenance below ground enabling a worker to be secured by means of a harness to be lowered down the cover. 
     
     
         8 . The cover according to  claim 7  wherein the harness is secured by a cable which is positioned in the slot which is continuous from the centre to the perimeter of the cover as defined in  claim 5 .