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on the extent of cigarette smoking among the young persons, some acknowledging that they commenced this habit at 9 or 10 years of age... Sir Thomas Flitcroft, Certifying Surgeon for Leigh, refers to the physical condition of young persons who come before him, and expresses the opinion that this is steadily improving. Dr. Stacey, Certifying Surgeon for Sheffield, comments on the value of conditional certificates as saving much hardship by rejection, and as a means of directing treatment beneficial to the young person, which he has found is largely carried out. Dr Badger, Certifying Surgeon for Penicuik, at the request of one firm, examined the vision of 114 female workers, their ages varying from 18 to 60, the average being about 30. The request from the firm was made on account of complaints about flaws in the work. Dr. Badger stated that the work was carried out in a very well lit airy compartment. Of the 114 workers, 25 had defective sight to such an extent as to make their work inefficient; the rest of the workers had normal vision. All the workers found with defective vision were subsequently fitted with glasses. Dr. Badger reports that the glasses improved the vision of every one of the 25 workers from 5 per cent. to 40 per cent. Some of the workers, seen after they obtained their glasses, stated that their work was now easier and more efficient and did not cause so much strain on the eyes. The value of such an examination, with the necessary correction of the vision, cannot be over-estimated for any occupation where good sight is required. The economic loss, both to employer and to employed, where defective vision is allowed to continue uncorrected, is very great.



G. Scott Ram, O.B.E., M.I.E.E.

The year under review has been abnormal, mainly on account of the prolonged coal strike, the results of which have been apparent in various ways. The precise effect on the output of electricity from the public supply generating stations will not be generally known until the annual returns are published. These will doubtless show a falling off in the districts serving shipbuilding, iron and steel, and other heavy engineering works, many of which were practically shut down for six months or more, whilst in other districts there may even be an abnormal growth due to increased factory motor load and domestic heating and cooking demands. Difficulty in obtaining fuel caused many works having their own power plants to shut down, and to realize the advantages of a public supply, which they have since adopted. Although public lighting was reduced and restrictions were placed upon lighting of shop windows and advertisements, etc., and private consumers were enjoined to exercise economy, the increased adoption and use of electrical heating by the latter must in many districts have more than counterbalanced any economies effected in the use for lighting. The remarkable feature of the whole affair was that the public electricity supplies were maintained all through—with the help, of course, of imported coal and oil.

The passing of the Electricity Supply Act at the end of the year marks the beginning of a new era in the electricity supply industry, the intention being that there shall be established a cheap and abundant supply wherever it may be needed. Although certain large schemes have been in abeyance pending the passing of the Act, and others have been delayed owing to manufacturing difficulties due to the coal strike, there was nevertheless marked activity in the electrical supply industry during the year. Several large new generating stations were placed in commission and important additions were made to others.

The number of reportable electrical accidents notified was 338, including 17 fatal cases, as against 414 and 24 fatal in the previous year. This reduction of about 18 per cent. is mainly attributable to the coal strike, as it has occurred almost entirely in the districts comprising the heavy iron and steel works and shipyards.

Thirty-two of the accidents occurred on high-tension systems, 22 of them, 4 fatal, being in generating stations or sub-stations of authorised public supply undertakings. As usual, most of these accidents-16, including 3 fatal-occurred to persons cleaning or

otherwise working on or adjacent to live switchgear or other apparatus. This class of accident, even when not fatal, is apt to be extremely serious, the victims in several cases losing a limb or being otherwise crippled for life. In most cases the work was in charge of an authorised skilled person, who in several was himself the victim. Mistakes, little distinguishable from carelessness, non-compliance with the standing rules of the station, or momentary inadvertence, are usually the cause.


The first of the three fatal cases was in a sub-station where the 11,000-volt switchboard was in three sections. These sections were inter-connected and also fed from the power house. section was about to be cleaned and had been made dead with the exception of the oil switch on the incoming connector from one of the other sections. It had been overlooked that this should have been isolated at the other section. In the second case work had to be done in an oil switch cubicle of a sub-station

switchboard (33,000 volts). The necessary isolating had been done by the victim himself, an authorised person. After completing the work he got into the isolating cubicle above and made contact with the live side of an isolator. It is thought that he intended dusting the insulators, having forgotten that one side would be live. In the third fatality, extensions were in progress to a 6,600-volt switchboard. A contractor's electrical fitter who had been employed on this work opened a cell of a part of the old switchboard which was live, apparently with the object of tightening the isolating switch contacts, a similar operation to that which he had just been engaged upon on the new portion. His action was inexplicable, as he could not have mistaken the cell for one of the new ones, as it was the fourth away from the new portion, and he had deliberately opened the lock by means of a file.

Of the similar accidents not ending fatally, one occurred to a highly qualified engineer. He obtained the keys of a certain switchboard cell in order to examine a bolt which was no longer required. Momentarily forgetting that the conductors were live he reached into the cell. His injuries were very severe, including the loss of an arm. In another case a man working in a dead cubicle went away for a few minutes, and on his return inadvertently went into an adjoining cubicle which was live (6,600 volts), and made contact with a live terminal.

Whilst highly skilled persons are thus liable to make disastrous mistakes in moments of inadvertence or otherwise, it is hardly to be wondered at that persons competent only to work under immediate supervision of authorised persons should meet with accidents. Such accidents occur every year in the course of cleaning operations. Cleaning of high-tension switchgear is a very necessary operation, and is constantly being undertaken. Usually it is carried out by workmen who may have but little technical knowledge, but who, working under the immediate supervision of an "authorised person," may be trusted as

competent for what they have to do, and particularly to do nothing more than they are instructed to do. In the case of switchgear completely enclosed, as in locked cubicles of which one or more at a time can be opened and made entirely dead, no harm can come to unskilled labourers engaged upon the work. Where, however, the live gear is in any way accessible, as by the cell doors not being locked and readily opened, trained cleaners with a certain amount of technical knowledge must be employed, even though under close supervision. Considering the large amount of this work which is constantly going on the accidents are very few, and are usually due to the cleaner being too keen on his work, thus, having finished the work in one cubicle of a switchboard, he may proceed to another without waiting for instruction from the authorised man in charge, who may be otherwise momentarily engaged, and meet with disaster. Six accidents of this nature occurred during the year. In one case the cleaner was engaged at an oil switch cubicle at ground level. The isolators above were in open fronted cells, out of reach from the floor. Having finished in the oil switch chamber he climbed up and started to clean the isolators (11,000 volts), the man in charge having gone to the other end of the room to answer the telephone. received severe burns to hand and feet.


In another case where cleaning was in progress in one cell the authorised man in charge opened the door of a live cell (also 11,000 volts) to refresh his memory as to what it contained. The cleaner having completed the one cell and seeing the door of the other open, assumed that it had been opened for him, and reached in before the superintendent, who was momentarily looking the other way, could stop him. His injuries were very severe and involved the loss of an arm.

In a somewhat similar case an apprentice, after sweeping up the floor of a sub-station, entered a truck-type cubicle from which the truck had been withdrawn, and which he had been specially warned not to do, and started to clean the insulators. Although he got a shock between his hand and head on a 6,600-volt system, he was not seriously injured.

In another case a truck-type cubicle in a sub-station was being overhauled by an electrical fitter and his mate under the supervision of a mains engineer. The latter was called away for a short time and instructed the two men to do nothing further until he returned, all live parts being left protected in the meantime. Soon tiring of waiting the fitter decided to carry on, and in order to examine the back contacts, shoved the truck into position and removed a part of the side panelling, in order to see inside. He then got his mate to hold a candle in the opening, in doing which he touched a live conductor, 6,600 volts. Whilst the fitter's desire to carry on rather than to remain idle may have been praiseworthy from one point of view, his disobedience to orders, besides nearly causing the death of his mate, constituted

a breach of the Electricity Regulations, for which he rendered himself liable to prosecution. This aspect of such conduct is not generally realised by subordinate employees in electrical stations.

In another case, through the combined carelessness of employees in a municipal power station and a contractor's foreman, in not definitely informing themselves of the connections of some new switchgear put into use for the first time, a labourer received a shock and severe burns, through his head coming into contact with a live conductor at 6,600 volts. It is not always realised by engineers of such stations that so soon as new switchgear has been put into use for the purposes of the undertaking they are responsible for the safety of any contractor's workmen who may still be engaged upon it.

Two accidents occurred in the course of earthing high tension switchgear preparatory to working upon it due to mistakes in isolating. Both could have been prevented if a test had first been made by a suitable indicator.

A fatal accident of an unusual kind happened in a large traction substation. A motor generator (6,600 volts) after being under repair had been running on load for a couple of hours when a short circuit occurred in the stator of the motor with a violent explosion. One of the attendants who was passing at the time was killed, apparently by the shock of the explosion. He was severely burned and his clothes were set on fire. Although the explosive energy released on a short circuit on a large system is often demonstrated by the destruction of switch cells or other apparatus, it is not often that anyone is caught in this way. A somewhat parallel case, however, occurred in a generating station where an attendant was passing the back of a switchboard when a short circuit occurred on one of the feeders, causing the isolating switches to blow out, and an arc to spread across the contacts, short-circuiting the bus-bars. He received burns, but not very severe. In both cases the arc was cleared within a second or so by the main circuit breaker operating.

Two fatal accidents occurred to "skilled" persons deliberately taking unnecessary risks. In one case an engineer surveyor of an Insurance Company who were negotiating for the insurance of the electrical plant in a works' substation, was taking notes of the plant, and wished to read the particulars given on a nameplate on the main incoming oil switch. For this purpose he leaned through the door of the cubicle, and presumably slipped and made contact with the bare conductors at 22,000 volts. It would have been quite feasible to have had the current cut off by the Power Company at a point outside the Works, but it would have involved some delay. In the other case, in a wireless transmitting station, a certain danger area was enclosed by a screen fence 5 ft. high, with a door normally kept locked and with a "danger" notice thereon. The door was interlocked with a main control switch and an earthing switch so that, should

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