Safety Engineering
the name given to the study of methods and apgiven to the study of methods and apin industry. Of recent years the matter has received much attention and has produced a nation-wide "Safety first" campaign. Its purpose is to reduce injury and loss of life caused by preventible accidents and it seeks first to introduce SAFETY LAMP various safety devices, and secondly to educate the workers and the public to a and thoughtfulness in a world in which the use of mechanical devices is continually on the increase. Contrary to general belief the education of the worker realization of the need for greater care is found to be far more important than the use of mechanical safety devices. In sion of Wisconsin the statement is made: "We must conclude that the great majority of accidents are not preventible by guards. a report made by the Industrial Commismaking accidents upon them impossible, one-fourth of all accidents." In other accidents. words, carelessness is the chief cause of one-fourth of all accidents." In other then we would have eliminated just about on every machine were perfectly guarded, If every danger-point then we would have eliminated just about accidents. ly being introduced and are, already, countless in number. They vary from ing machinery to automatic devices which Mechanical safety devices are constantprevent, for instance, the moving of an simple metal guards placed around movcrossing to elaborate automatic signaling devices. Safety engineering also concerns itself with the prevention and extinguishelevator until its doors have been closed; ing of fires, the provision of fire escapes, and from simple gates across a level itself with the prevention and extinguish- devices. Safety engineering also concerns crossing to elaborate automatic signaling and from simple gates across a level ing of fires, the provision of fire escapes, and tunnels, and with many other matters far too numerous to mention. ters far too numerous to mention. light carbureted hydrogen, which is frequently disengaged in large quantities from coal seams, is mixed with 10 times SAFETY LAMP. It has been long its volume of atmospheric air, it becomes ders 10 times its bulk of atmospheric air unfit for respiration, and the choke damp thus produced is often as fatal to miners highly explosive. Moreover, this gasfrom coal seams, is mixed with 10 times of discovering some means of preventing these dangerous results, Davy instituted those important observations on flame as the primary explosion. With the view safety lamp. He found that when two vessels filled with a gaseous explosive mixture are connected by a narrow tube, and which led him to the invention the diameter of the tube, its length, and the conducting power for heat of its material bear certain proportions to each the contents of one fired, the flame is other; the flame being extinguished by which led him to the invention of the those important observations on flame these dangerous results, Davy instituted cooling, and its transmission rendered impossible. In this experiment high conducting power and diminished diameter compensate for diminution in length; and to such an extent may this shortening of other; the flame being extinguished by SAFETY AT SEA length be carried that metallic gauze, which may be looked on as a series of very short square tubes arranged side by side, completely arrests the passage of flame in explosive mixtures.
The first lamp which would safely burn in an explosive mixture of gas and air was contrived in 1813 by Dr. W. Reid Clanny of Sunderland. Into this lamp DAVY SAFETY LAMP fresh air was blown through water, and heated air escaped through water by means of a recurved tube. Such a lamp was unfit for ordinary use. George Stephenson invented a safety lamp which was tried at the Killingworth pits in 1815. Both Clanny and Stephenson applied wire gauze cylinders to their lamps after Davy's came into use, or at least after a communication about it had been made to the Royal Society in 1815. Portable electric lamps are now in general favor, but they give no warning of gas, and in mines much affected by gases the oil-safety lamp is in use.
SAFETY AT SEA. The principal dangers to life at sea are connected with stranding, foundering, collision and fire.
These dangers are being reduced year by year through improvements in the design, construction and equipment of SAFETY AT SEA ships and through inventions and improvements in the conditions of navigation, many of which are revolutionary in their nature. Radio telegraphy is finding what is perhaps its most beneficent application, in communication at sea, where a ship in distress can now give notice of its danger to other ships and to shore stations hundreds of miles away; and a very recent development makes it possible for a ship hastening to her assistance, to locate her not only by reports of her latitude and longitude but by the direction from which her signals are coming. The same invention which makes this possible, the "Radio-direction Finder" makes it possible also for shore stations to guide a ship at sea and in a fog as accurately toward the entrance of the harbor she is seeking as if the lights and buoys of the entrance were plainly visible.
A similar device for determining accurately the direction of sound, makes it possible for ships in a fog to locate and avoid each other, thus enormously reducing what is perhaps the most serious of all dangers at sea, collision in a fog.
It is even proposed today to lay a wire along the bottom of a channel and, by sending through it a current of electricity, to enable a ship to follow the channel perfectly, no matter how tortuous it may be; and this in the thickest fog and with the helmsman blindfolded.
The service of weather observation and report is improving steadily and both its sources of information and the area covered by its warnings are being greatly extended. Dangerous storms are located almost at their origin and tracked not only day by day but hour by hour, notices being sent broadcast through the air predicting their future movements with such accuracy that they are easily avoided by ships which can afford the time to give them a wide berth. The latest plan of the United States weather service is to maintain a number of small vessels during the hurricane season, in the Caribbean Sea, where most of the Atlantic tropical storms have their origin, to study these storms by actually seeking them and accompanying them on their course. In spite of all that has been done and all that can be done to reduce the dangers of the sea, disasters still occur and will continue to occur; and the problem of minimizing their effects is receiving more attention than was ever devoted to it in days when the dangers were far greater than at present and disasters far more frequent.
The details of construction of ships and especially of ships carrying passengers, are prescribed by laws enforced by careful inspection which begins with the building of the ship and follows it SAFETY AT SEA throughout its whole career. The ship having been completed in accordance with requirements, the law looks next to the officers and crew and to the equipment of life-boats and other safety appliances.
Rules cover the nature and stowage of the cargo and the depth to which the ship may be loaded. A limit is set to the number of passengers that may be carried, and these must never exceed those for whom accommodation is provided in lifeboats and life-rafts of approved type. Rules for the avoidance of collision have been drawn up through international agreement, covering as fully as possible every situation that can arise when vessels are meeting or crossing each other's courses.
Among the most important features involved in the prescribed designs of ships, is the requirement uirement for a thorough subdivision of the ship into water-tight compartments of such size that the flooding of one or even two of these compartments through collision or stranding will leave the ship with sufficient buoyancy to remain afloat. Where communication is necessary between adjoining compartments, water-tight doors must be fitted with arrangements for closing quickly, and in certain cases, automatically.
Other requirements as to the ship itself have to do with boilers and machinery, with steering gear, with pumps and firefighting apparatus. The rules governing life-boats are especially strict and include methods of stowing and launching, -features which were too often neglected until made the subject of special rules in recent years.
The laws which have been mentioned as covering the construction of ships have reduced to a minimum the chances of foundering in the open sea. Disasters of this nature, formerly among the most common of disasters at sea, are now extremely rare and should be practically unknown except when a small ship is contending with a hurricane of great violence. A vessel of size sufficient to be rated as a passenger carrier, constructed in accordance with present-day laws, with water-tight compartments that are in fact water-tight, with cargo properly limited and properly stowed, and handled in accordance with the dictates of sound seamanship, should be able to ride out any gale so long as she has plenty of searoom. It is near the shore that gales and fog are most to be feared; for there conditions may prevent the manœuvers that would insure safety.
Danger from fire, once the most dreaded of all sea dangers, has been robbed of most of its terrors by the substitution of steel for wood in the interior fittings of steamers as well as in construction of SAFETY AT SEA the hulls; and it is only when a cargo of explosives or inflammable material is carried that the danger from this source becomes great. Here, again, modern law steps in to protect passengers, by limiting the conditions under which inflammable cargo, and especially explosives, may be carried. As a rule, they are not permitted at all on ships designed primarily for passenger traffic.
No degree of perfection in the equipment of a ship can insure the safety of the ship or the passengers and crew unless the use of the equipment is thoroughly understood. On a well-ordered ship, drills are frequent, especially in fighting fire and handling boats, and these drills are doubly useful if they include participation, necessarily superficial, -by the passengers. Every passenger should understand the significance of danger si signals and what his part is to be in co-operation with the officers and crew. Every passenger should be furnished a list of all signals which concern him, together with information as to the location and fitting of life-belts, and, most important of all, the number and location of the life-boat to which he is assigned.
A preliminary drill at lowering boats should always be held before leaving port and the boats inspected as to their fittings and equipment; and as soon as convenient after leaving port, a drill at "Stations for Emergency" should be held, and each passenger required to go to the life-boat which he is to enter in case it becomes necessary to abandon the ship. boats, In addition to the normal equipment of the boats, each one should be provided with provisions and water sufficient for all occupants for at least a week. Other important items to be insisted upon are: compass, lead-line, lantern, rockets and other fire-works for signaling, buckets for bailing and other necessary purposes, mast and sails (may be useful for "seaanchor"), navigational books and instruments. Information should be given to all boats, of the course and distance to the nearest land or steamship lane.
Boats should be instructed to keep together if possible under authority of the senior officer of the group.
The rules regulating all of the matters that have been described are for United States vessels established by Congress and by regulations ons of the "Steam Boat Inspection Service" of the Department of Commerce, and are published in a pamphlet entitled "General Rules and Regulations prescribed by the Board of Supervising Inspectors."
For many years before the matter of safety at sea was taken up seriously by various maritime governments, many of SAFETY VALVE SAGA the questions involved were efficiently it is used in lieu of the more expensive controlled by private companies interested in marine insurance. These companies based their rates for insurance upon requirements of their own making which covered primarily matters involved in the safety of the ship and cargo, but which at the same time covered, necessarily, safety of life, though omitting many details now covered by laws which make safety of life their first concern. The principal companies of this kind are the following: The Bureau Veritas, French (1828); Lloyd's Register, British (1834); The German Lloyd, German (1867); and The American Bureau of Shipping (1867). These companies will doubtless continue their existence and activities, which are purely commercial, not humanitarian, although their work is to a great extent duplicated by the governmental agencies above described.