Danger! Hydrogen Sulfide

foreign [Music] [Music] [Music] [Applause] so [Music] [Applause] [Music] danger h2s is a familiar sign posted in petroleum refineries and chemical plants throughout the country it is a warning to all that hydrogen sulfide or killer gas zap to be present that people unskilled in dealing with it should stay away this is the story of that invisible killer and of the vicious threat it poses to human life but it is also the story of how men in medicine and industry have learned to harness its beautiful power and safeguard the lives of thousands of workers through education rescue techniques and protective equipment [Music] although the action takes place in one refinery and petrochemical plant the information applies to any industrial plant where h2s has used the chemical agent or where it is produced as a manufacturing byproduct [Music] in a refinery much of the lethal hydrogen sulfide arrives in tanker shipments of sour crude oil or nafta the term sour is applied to those materials which contain high percentages of volatile sulfur compounds including h2s [Applause] [Music] tanka crew men and men handling cargo hoses must be ever alert to avoid breathing h2s when working with such shipments [Music] from tankers the sour crude oil napla is pumped through miles of pipelines to storage tanks where the h2s will again lie in wait for a careless human act [Music] minutes after a filling operation starts the atmosphere in a tank can contain enough h2s to kill a man in seconds and without warning measuring the contents of such tanks these gauges know that only wise men are live men so they take the proper precautions one of which quite often is to have a buddy standing by with his fresh air mask at the ready well-meaning but ill-prepared rescuers often become victims themselves on a processing unit where the prime purpose of the operation is to remove h2s from the feedstock dangerous amounts of h2s may leak from a faulty packing gland and a pump and set the trap for the unwary or careless worker or venting a pump may set the trap [Music] or inspecting a sewer or opening a pipeline many cases the manufacturing process itself generates large quantities of h2s depending on the pressures within the system the condition of the detection and alarm system and other equipment the normally safe area could at any time become a gas chamber for an innocent victim [Music] this operator uses a detector to determine the exact source of the h2s leak as h2s passes through the glass tube containing grains of the chemical the grains turn from gray to black but what about the question how and when is h2s fatal to the human system in a concentration of as little as one tenth of one part of h2s in the million parts of air a slight odor of rotten eggs can be detected by most people for others with a less acute sense of smell odor detection would start at slightly higher concentrations the odor becomes stronger as the concentration is increased but then due to a dangerous characteristic of h2s the sense of smell is soon fatigued or deadened and at a concentration of about 100 parts per million after a short period of exposure the average person might assume that the h2s had dissipated because he could no longer smell it this should be a warning sign at about 700 parts per million or seven hundredths of one percent of h2s in air breathing stops and unconsciousness occurs between five and sixty seconds after exposure this varies from individual to individual depending on a state of health [Music] for example if this 5 ounce glass were filled with h2s and dropped into a 55-gallon drum containing clean air the resulting mixture could knock a man out in less time than it takes to give this demonstration much of the information we have on h2s and its effect on the human system we owe to men like dr h.w gerard shown here addressing a group of refinery workers dr gerard a prominent toxicologist has done extensive work and control experiments to study the effects of h2s on white rats a safer life for countless industrial workers has resulted from such studies in this demonstration before this group of processed men dr gerard will show how a living being reacts to h2s poisoning and how artificial respiration applied in time can quickly restore the victim to normal he places a healthy specimen in a jar under room conditions he seals the jar next he starts a chemical reaction to generate h2s in the jar he adds a few drops of hydrochloric acid to a small amount of iron sulfide in the jar this will generate a high enough concentration of h2s to cause acute h2s poisoning as the h2s content rises a human being in the similar conditions might well be thinking i smell rotten eggs now i don't smell anything now my eyes are burning and it's hard to breathe [Music] dr gerard quickly removes the raft of fresh air a must in all h2s rescues he notes the usual symptoms generalized convulsions and the normally pink nose has a gray power the same symptoms displayed by a human victim except that with a human the entire face turns gray the heart is still beating as it will for five to ten minutes without respiration but artificial resuscitation must be applied immediately in order to get oxygen into the bloodstream and then to the respiratory nerve cells and brain [Music] accomplished point to remember get fresh air into the victim's lung immediately or his chance of survival is slim another detector of h2s is a disc of white paper soaked in lead acetate if it turns to a metallic gray the atmosphere is unsafe the darker the gray the more lethal the atmosphere it works on the same principle as this detector shown earlier we now know more about h2s and about how laboratory animals have been successfully revived but what can you or i do to revive a victim the simplest and most successful technique of applying artificial respiration to a human victim is mouth to mouth the rescuer literally breathes new life into the victim here a medical staff member demonstrates mouth-to-mouth resuscitation on a specially designed plastic dummy to a group of employees now why is mouth-to-mouth resuscitation only demonstrated [Music] the simple reason is shown on this chart that this technique is the surest method known when oxygen resuscitators are not available no method is foolproof however as this chart shows [Music] assuming that the victim has been removed to a safe area the first point is to assure that his breathing passage is open note as in this model that when the head is tilted back throat passage opens the tongue is moved to the front of the mouth and any loose stenches or foreign articles are removed with the forefinger the hand next to the victim's body is placed under his neck as a fulcrum the other hand placing the forehead tilts the head backwards with the throat passage clear the nostrils are firmly pinched closed with the thumb and forefinger the rescuer fits his open mouth over the victims and forces air into his lungs for about two seconds he removes his mouth for about two seconds he repeats this cycle for as long as needed note that when he withdraws his mouth he turns his head to watch the victim's chest he does this for several reasons first it puts his ear next to the victim's mouth in order to hear or feel the breath being expelled you can also see how much the chest contracts both indicate how much air has reached the lungs it also helps the rescuer time himself and to know when the victim starts breathing in h2s poisoning respiration will start when enough air has replaced the h2s and the nerve cells but now that we know more about h2s let's return to the poor fella who did the wrong thing at the start of this film can you survive let's take a close look the rescuer calls for help [Music] drags the victim to a safer spot and applies mouth to mouth immediately [Music] help arrive [Music] success the victim starts to revive training and quick action pay off [Music] foreign