Cap lamps

Downhole repair cap lamp Methane explosion, Methane combustion 13... 

I recall the case of a miner who was working in an underground area where there was no illumination. The only source of light was from his cap lamp. The walking surface was full of mud and covered with a layer of muddy water. One day, while walking down this drift, he stepped into an 18-inch hole hidden by the muddy water, twisted his ankle, and fell to the ground in pain. Despite his immense pain, he continued to work for the next 6 hours until he collapsed in agony and called for help. 

Lamp The electric cap lamp worn for visibility also, the flame safety lamp used in coal mines to detect methane gas concentrations and oxygen deficiency. 

A large underground mine had a write-on board erected in the area where the miners collected their cap lamps at the beginning of their shift. The board listed all the underground near miss incident reports and a separate column on the board showed what action had been taken for each reported event as well as the completed dates. Miners could follow the progress of their reports each day because of this system. 

Each employee undergrovmd shall have an acceptable portable hand lamp or cap lamp in his or her work area for emergency use, unless natural light or an emergency lighting system provides adequate illumination for escape. 

A small fan is mounted in the rear of the helmet to draw dust-laden air through a filtering system the resulting cleaned air is directed behind a full-face visor and over the wearer s face. Seals are provided along both sides of the visor so that exhaled air and excess clean air are allowed to exit the helmet at the bottom of the visor. Also, these face seals and additional seals inside the helmet limit contamination from unfiltered air. The fan is externally powered by a rechargeable battery smaller than a conventional cap-lamp battery to be worn on the miner s belt. 

The extent of the restricted vision often meant that a man from the heading team had to be deployed as a spotter for the driver, positioning himself in front of the machine and signalling by arm and cap lamp movements to direct the driver s positioning of the drill booms. Given that such machines are tracked (and therefore difficult to manoeuvre accurately in limited space) and that there was often less than a metre clearance on each side of the machine, it is clear that any error on the part of the driver could create considerable risk forthe spotter . Equally, errors in drilling the required firing pattern holes could result in subsequent risks. 

In a study of the retrofit improvements to the ergonomics of urrderground locomotive cabs (Rushworth et al., 1993 orRushworth, 1996forsirmmary)itwas noticed that there was no illrrmination provided on the instrument panel of several of the then commonly used locomotives. The problem was exacerbated on those fitted with windscreerts as the driver could not use his cap-lamp as this created back reflectiorrs partially obsctrring his view ahead. 

Misreading of loco displays Some locos are fitted with glass windscreens which cause reflections when cap lamps are used. The driver s displays are not illuminated and cannot be read without a cap lamp. Drivers use the less bright setting on their cap lamp but it is an unsatisfactory compromise and drivers acknowledge that errors are made. 

Illumination would be provided by intrinsically safe cap lamps (attached to helmets). 

At present, a fraction of the generated end-of-life FLs are being collected by the informal sector (kabadiwalas), largely from the large-scale consumers (industries and corporate sectors). The lamps are then disassembled by crude methods into useful components such as glass tubes (glass and phosphor powder), aluminum end caps, polypropylene caps, and electronic ballasts (electronic components which contain metal). The major processing hubs for the various components exist as follows ... 

Coal Mines, Determination of Firedamp and of Coal Dust In Atmospheres of. Although many instruments have been designed to detect the presence of firedamp (or rather methane) in mine atmospheres, the principles of the flame safety lamp (Davy-type lamp) still form the basis of many detectors. The Davy lamp invented in 1815 is briefly described under COAL MINE EXPLOSIONS AND FIRES and it is stated that each US mine should have at least two Davy-type lamps to serve as detectors of firedamp or of lack of oxygen. If firedamp is present in small quantity, the flame of Davy lamp elongates and if the gas is present in considerable quantity, the lamp becomes filled with blue flame. For more definite detection of gas, the flame of the lamp is lowered until the yel part is at a minimum. Then the gas will be discernible as a small blue cap over the flame. This method is described in Refs 1, 9, 12 25. Some investigators consider that the safety lamp method of detection of firedamp is not very reliable (Ref 7)... 

A benzene (2 ml) solution of selenide (0.33 mmol) and 1-octene (1 mmol) in a screw-cap pyrex test tube was bubbled with argon gas for 30 min., then the mixture was irradiated with a 450 W mercury lamp (Hanovia lamp) under an argon atmosphere (48 72 h). After the reaction, the solvent was removed and the residue was chromatographed on silica gel (eluent acetonitrile/ethyl acetate = 1/5) to give 1,2-adduct in 83% yield [65]. 

A curious experiment has been described by Price 1 in which a flame is obtained very similar to the inner flame of the Smithells separator. The experiment consists m fixing a glass chimney over the base of a Bunsen burner, and a horizontal wire an inch or two above its upper end (fig. 11). If the height of A above the burner and the rate of flow of gas are correctly adjusted, upon applying a light at C the gas bums with a pale blue flame, and bears a resemblance to the gas cap of a miner s lamp. 

For application in increased safety - e tubular fluorescent lamps shall be of the cold starting type fitted with single-pin caps (type Fa 6 according to IEC 60061-1). These lamps do not need a starter... 

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