Learning by accident edited By Teresa Robertson And



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LEARNING BY ACCIDENT

Edited By



Teresa Robertson

And
James A. Kaufman

Volume # 3
The Laboratory Safety Institute

192 Worcester Road

Natick, MA 01760

Copyright 2003; Revised 2005



The Laboratory Safety Institute


192 Worcester Road, Natick, MA 01760

      1. Fax: 508-647-0062

Email: info@labsafety.org

Website: http://www.labsafety.org

TABLE OF CONTENTS




Table of Contents I




Acknowledgements II




Introduction III




Accident Activity Form IV




Accident Summaries 1


Index 92

Appendices:

I. About the Editors 102

II. About the Laboratory Safety Institute 103

III. How you can help 104





ACKNOWLEDGEMENTS

We wish to thank the many science teachers who contributed the anecdotes, stories, newspaper articles, and accident reports that are the heart of this book. Thanks to Barbara Jerome for her help with the manuscript typing. And, thanks to Don Dix for introducing me (JAK) to the importance of laboratory safety.



INTRODUCTION
Since the founding of the Laboratory Safety Institute in 1978 as the Laboratory Safety Workshop, I've been involved in offering lab safety training programs for science teachers. One of our activities during these training programs is the sharing of accident experiences. Teachers spend a few minutes writing an accident summary and then describe and discuss these accidents with each other.
Several things invariably happen. Teachers are amazed by both the number and seriousness of the accidents. Many teachers have had similar experiences. Teachers realize that they have been "lucky not to have had a particular accident”. And, teachers are glad to have heard these examples to share with their colleagues and students.
That's what this book is all about. A sharing of anecdotal accounts of laboratory accidents. Hopefully, it will be a valuable resource for you to experience vicariously the many ways that people got into trouble in the lab. Hopefully, it will give you real life examples to share with your students.
I should point out that although these accident accounts have been edited for general technical correctness and consistency of style, no attempt has been made to verify the descriptions. Some accidents may, in fact, be described more than once by different teachers.
Somewhere in Tom Peters' In Search of Excellence, I read a story about a computer scientist who asked his computer: "when will you learn to reason like a human being?" The computer spun its tape drives and flashed its lights for a few moments and then spat out a piece of paper. On the paper was the answer, "That reminds me of a story."

That's how we learn best. We remember stories and we extrapolate from them easily. Perhaps, that's why Peters is so successful. It's been said that whenever data competes with folk lore, folk lore wins 21 0!

That's the incredible power and value of these accounts of laboratory accidents. Use them in your science teaching to help you identify potential problems. Use them to help get the message across to your "invincible" students. They'll remember these true stories. Use them so that "Learning is no Accident".

On the next page is a copy of the "Accidents" handout that we use in our science training programs. Please feel free to photocopy this page and use it in your science department for a group activity. And naturally, we would be delighted to receive contributions from you and your colleagues for the next edition of LEARNING BY ACCIDENT.




ACCIDENTS

How often have you heard someone say, "I don't have to worry about that. I've never had an accident." You can see the person's bad habits and the increased probability of disaster striking.


For many people, the "remoteness" of accidents makes them seem unlikely. Yet, each of us is probably familiar with one or more serious accidents with which we have had either direct involvement or intimate knowledge.
The sharing of these experiences heightens our awareness of the dangers in the lab.
Please spend about twenty minutes writing a summary one, two, or three of the most serious laboratory accidents with which you are familiar. Who? What? When? Where? Why?
What were the errors that were made? What might have been done to prevent such an event from occurring?
Then, please take turns reading some of the descriptions of the incidents and allow the others to identify what they believe to have been the errors and what might have been done to prevent the accident.
I would like to collect these written descriptions to include them in a permanent collection for distribution to other science teachers. Please indicate if you wish to place any restriction on use or distribution.

Acetic Acid

1001. During a high school biology class a student teacher spilled glacial acetic acid on the floor. He attempted to wipe it up with some paper towels. He severely burned his lungs and ended up in the hospital. He should have neutralized the acid with base then mopped up the residue. (1341)
Other cases include: 1012

Acetone
1002. A serious accident I witnessed took place in a university organic chemistry lab when a lab demonstrator lit a burner down the desk from a student drying glassware with acetone. A very interesting river of flame formed flowing back to the surprised student holding the acetone bottle. He dropped it and it remained burning until someone had the presence of mind to throw a fire blanket on it. The student was burned quite badly and cut on broken glassware in the process of jumping away from the flame. (1240)
Other cases include: 1031, 1095, 1450

Alcohol Burners
1003. A science teacher in a middle school was using alcohol burners in a non-science room. An explosion occurred when the open burner dropped. Four students were burned. A law suit is still in litigation. The teacher quit because of questioning during investigation. She had complained in writing about safety concern but the department chair said it was part of the state curriculum that that experiment should be done. (1023)

1004. In the early days of IPS when one school was in the midst of a population explosion the program was selected because of adaptability of non-laboratory rooms for a lab centered course. Alcohol lamps, for example, replaced the need for gas service.

A former social studies teacher was "pushed" into teaching the course, which he hated, in an ordinary jr. high class room.

Near the end of a period when students were replacing their hot alcohol lamps on the supply table, one of the students upset an open alcohol supply beaker. The spilled alcohol ignited and cascaded to the floor at the feet of several students who were gathered around the table. They panicked and began to run. Although there was a fire extinguisher in the room, the teacher did not know how to operate it. Finally one of the students figured it out and extinguished the flames. (1045)

1005. In 1982 in an eighth grade IPS class students were using alcohol burners with a rusty top, spilled alcohol on the lab table by turning the burner over. The entire table flamed up. I moved everyone back and let it burn out since the table was flame proof. (1103)
1006. After explaining the proper use of alcohol burner one team of two junior high students decided to relight their burner. While one student was lighting the burner the other was pulling on the wick with a tweezers. In doing this he also pulled up the cork a bit. The fumes ignited and blew the cork off the burner splattering fluid on one of the students shirt. I happened to be standing with my back to them but when I turned around I was able to put out the flames with my hands. (1268)
1007. The students were sitting four to a table while doing a lab experiment. The alcohol lamp was used to heat up some water. At one table one lamp fell over and dropped to the floor. The alcohol spilled out and caught fire spreading along the floor.

The students knew were the bucket of baking soda was and how to use it. The fire was put out quickly with no injury.

I always start the term with the alcohol lamp lit and then take some alcohol and spread it on a table top. I then light a match and set it on fire. It is quite dramatic. I then take a handful of baking soda from the red bucket and throw it on the fire. The fire is out. I have one student do it again. The point is then remembered. (1317)
1008. While working with alcohol burners a student poured some on a wooden table that was the lab area. It caused the student next to him to get his fingers burned. The table was old and probably had many different substances on it. The flame did not go out easily. (1395)

1009. A team of seventh graders was using an alcohol burner in an experiment. When one student attempted to burn the burner off by the knob the lamp was over turned. There were flames all over the table. This happened about fifteen years ago. (1416)

1010. This occurred many years ago in our junior high. A teacher asked a student to move an alcohol burner during a lab. The alcohol somehow got spilled and caught fire. The student was seriously burned. (1484)
Other cases include: 1065

Allergic Reaction
1011. My next-door neighbors were in the process of adding a second floor to their home. One Saturday the father was taking care of the children. During the day the father brought up rolls of insulation to the new addition. The children were in the room as the father worked.

That evening the youngest child, aged three, woke from a sound sleep crying and screaming with pain. The baby sitter was alerted and watched the child for several hours trying to soothe him back to sleep. After the parents finally came home they took him to the hospital when they noticed he was having difficulty breathing.

It was determined the child experienced an allergic reaction to the insulation which the baby sitter never would have anticipated. (1234)
1012. One student was washing a beaker over a sink. Another student emptied some acetic acid from another beaker into the same sink. Some drops from the acetic acid spilled on the first student's hand. The second student immediately informed the teacher who put the student's hand under the tap water and washed the hand thoroughly.

That night the girls father phoned and blasted the teacher. His daughters hand had swollen. She was allergic to acetic acid (vinegar). (1499)


Other cases include: 1145

Ammonia / Ammonium Hydroxide

1013. During the summer we did a program with kids developing blue prints by taking Diazo paper with designs shadowing areas of the paper. When exposed to light the yellow paper turned white, then by exposing the paper to Ammonium Hydroxide it turned blue and the kids could see the designs left by the shadowing. The kids loved it, our staff did not. When traveling with the container of ammonia in a hot car, the fumes often became too much to bear. Our solution was to carry the ammonia in an iced down cooler. (1133)

1014. When I was in high school our chemistry teacher opened a bottle of ammonia and asked a student to put his nose over the bottle and inhale. The student passed out. (1143)
1015. I became ill while making ammonia gas due to a lack of ventilation. This occurred in a chemistry class in 1966. (1384)
Other cases include: 1272, 1336, 1494

Ammonium Dichromate Volcano
1016. This happened at a college during a chemistry department open house in the early 1970's.

A showy, pyrotechnics display of an ammonium dichromate volcano was set up on a bench top with no access barriers to visitors who were circulating freely among several "live" chemistry displays. Without warning the four-inch diameter, two-and-one-half inch high volcano exploded well into the normally smooth pyrotechnic phase of the display. Burning embers struck a woman on the arm causing a second degree burn. The lady was very agreeable, graciously accepting first aid and apologies. She did not charge the college.

The college's authorities were notified and were predictably nervous. No similar experiments were performed as a result. The explanation of the explosion was never satisfactorily reached. I have since run the same demonstration behind proper shields. (1152)

1017. The teacher was demonstrating a volcano eruption using ammonium dichromate. The teacher thought the chemical would not ignite so he poured alcohol on the ammonia dichromate. He relit the chemicals. The volcano exploded with the burning alcohol splattering the students standing around the demonstration table. A number of the students were rather seriously burned. The teacher and the school were sued. The case was settled out of court. (1356)

1018. In an elementary class a teacher was demonstrating how volcanoes explode using ammonium dichromate. Sparks flew up and landed on the dress of a girl sitting in the front row catching the dress on fire. The girl was seriously burned. (1374)

Animals
1019. A child brought a pet squirrel to class. Someone opened the cage, and the squirrel bit a student. Very fortunately no infection. Classes should have no live animals in cages that students have access to. (1127)
1020. In 1954 a college junior was doing research on the life cycle of rattlesnakes. He had a mother and some young snakes in the locked area in the laboratory. One Saturday he wanted to show his girlfriend how the mother snake reacted to movement. He put his hand into the cage toward the mother but a safe distance. He did not notice one of the very young snakes was close to the back of his hand. The young snake bit him.

At the time I was the only student lab assistant in the building. I place a tourniquet on the arm and got him to the hospital. He was there for a week. (1148)


1021. We had a nice piece of undisturbed woods behind the high school on school property. It was ideal for ecological studies. We could take a class out for one or two periods of field work without the hassle of trip permits and buses. One time we were conducting plot assays - counting every plant and its size within a measured area. Suddenly we found ourselves being attacked by yellow jackets who had a ground hive right within one plot. Everyone was stung, one girl had to receive medical attention.

Moral: Carefully check the ground before taking a class out for field study. (1156)

1022. In a rural school in Montana a twelfth grade student brought a live rattlesnake to school for biology class. Rattlesnakes are very common in that area. The teacher put the snake into an empty aquarium, put a lid on the tank and a rock on the lid. After telling all the students to look but not to touch he went to the back of the room to work with a student needing help. A student in the front of the room opened the case, grabbed the snake and was using it to scare some girls.

The snake, which was being held just in back of the head, wiggled free far enough to reach around and strike the thumb of the student holding him. The boy was hospitalized in critical condition for several days. Anti-venom was administered several times. The boy was able to return to school several weeks later.

This was settled out of court with the teacher paying all medical bills. (1159)

1023. During the 1987-88 school year I had a student bitten by gerbils kept in the room. The parent wanted me to pay for the tetanus shot. I had instructed the class as a whole not to touch the gerbils. I have good control of my class all year. Four months after being instructed not to touch the gerbils during the five minutes of switching class the student asked if she could pet the gerbil. I was busy half listening and said yes. She was bitten. I sent her straight to the nurse. No shots were given, not problem from the bite. (1325)


Benzene
1024. In 1983 in West High School, Manchester, NH a chemistry teacher was working in the stock room standing on a stool. Apparently someone had left a container of benzene open. Water leaked through the ceiling from the roof, contacted a light socket producing a spark. The benzene vapor ignited. The teacher was knocked off the stool and rendered unconscious. He came to, crawled out of the room and was found by two other teachers. The fire destroyed the stock room. (1063)
1025. In our college organic lab, a student caused a benzene flash (with a Bunsen burner), leaving blackened strings of organic material floating around the classroom. Personally, I left the room. (1088)
1026. A student heated benzene and hit the flash point. A ball of flame shot up to the ceiling. No injury. (1145)
1027. During my undergraduate days I recall an accident that happened in an organic chemistry laboratory. A female student was cleaning a reaction vessel with benzene. The round bottom flask had a small opening. She was in a hurry to dry the flask in order to go on with the next step of the lab. She inverted the flask over a lit Bunsen burner. The benzene vapor ignited and the flask had the appearance of a rocket engine with flames shooting out. Fortunately the amount of benzene was very small; the fire burned it self out and no one was hurt. (1211)
1028. A college student was carrying a pan of benzene. A burner several feet away set the vapor on fire. His hands were seriously burned. (1445)

Bicycle

1029. A number of years ago the Canadian Youth Hostels Association had an accident occur on one of their cycling trips. Apparently the brakes on a young girls' bicycle had failed. She ran into a tree while negotiating a curve in a road.

She was paralyzed and in the ensuing law suit the Association was found guilty on the grounds that they were negligent in checking her bicycle for mechanical conditions. They did not check that she was fully informed on how to ride a bicycle. (1492)


Blender
1030. A twelfth grade male student in an Advanced Placement Biology lab was preparing a chlorophyll extract using spinach and a Waring Blender. The blender had clogged. The student removed the top of the container, reached in with his hand to stir the contents without turning off the blender. In so doing, the student freed the blades and lost a chunk of his index finger. His lab partners had tried to stop him but he had moved too quickly for them to physically prevent him from putting his hand into the container. (1302)

1031. The instructor was beginning to prepare a spinach extract for a student paper chromatography experiment. This is accomplished by grinding spinach in a blender using acetone to suspend the chloroplasts, then vacuum filtered to obtain the extract.

There were three factors contributing to this accident:

One, the blender in use was the common household "Waring" type with a glass container and a loose fitting, hard plastic lid.

Two, an excessive amount of acetone was added to the blender container at the start of the process.

Three, the high speed switch was pressed. The acetone surged up the inside of the container, splashed out the lid and ran down the outside of the container to the table top.

The acetone vapor traveled under the blender motor base where it was ignited by sparks produced by the rotating electric motor. The flash ignited the liquid on the outside of the container which ignited the acetone inside the container which in turn propelled the lid into the air.

A fire extinguisher was close at hand and the fire was put out quickly, the equipment cleaned up and the experiment was continued without further incident. Needless to say a stainless steel container with a screw top was put on order the next day. (1454)


Bromine
1032. One of my eleventh grade chemistry students wanted to see the vapors from bromine. I told him to take the bottle to the hood and open it. He did, wasn't impressed and put the ground glass stopper back in the bottle. Then he decided to look at the liquid so he rolled the bottle on its side. The stopper came out of the bottle, bromine splashed on his hand and he dropped the bottle in front of the hood. He got scared and someone yelled for me. I told him to wash it off and then I realized I didn't know what else to do so I had to get the poison control number and call them and the fire department.

The bromine caused burns on his hand that left a scar. I am now overly sensitive to students handling any chemical out of curiosity. (1104)


1033. In my college organic lab, bromine was being added to a flask on a hot plate. The bromine was being added from a one-pint bottle which slipped out of the students hand and fell on the hot plate. The room turned orange but luckily all the students escaped safely. When an instructor went to open the windows, I noticed he was quite seriously burned. (1200)

1034. Samples of chemicals were set up in a display in my sophomore high school class. The students were directed to examine the materials but not to open the containers. I specifically indicated that the bromine sample was not to be opened, particularly due to its high vapor pressure. Of course one student opened the container and got some bromine on his leg.

God was on our side because just prior to that week I had read about how quickly bromine can be absorbed from skin by glycerin. The student was directed to rub glycerin into the spot, following it with water. No burns resulted!

I have since removed bromine from my element demonstration. The thought of bromine in a student's eyes was too frightening.

I have also learned that a solution of sodium thiosulfate would also have absorbed the bromine. (1219)

1035. I was a college junior taking Organic Chemistry and the lab for the day was the bromination of an alkaline. Liquid bromine was being added using a dropping funnel to a flask containing cyclohexene. The student working just to my left had failed to grease the stopcock on his dropping funnel before adding the 25 ml of liquid bromine to it.

The experiment was well in progress when this student noticed that liquid bromine was dripping outside the stem of the dropping funnel. He reached up to tighten or adjust the stop cock and the whole glass piece came out in his hand. Apparently the guard was either missing (if metal) or dissolved (if tubing) by the Bromine.

Bromine vapors quickly filled the air as liquid bromine spilled along the bench top and down onto the floor. Realizing the severity of the accident both lab instructors immediately evacuated the lab of all the students, opened all windows and sponged the liquid bromine into the nearby sink.

Both professors were out of work for the next two weeks with severe burns to their hands and nasal passages. None of the students were hurt. (1229)


1036. In a college organic chemistry lab in Hillsdale college I was working on a bromine lab. I was using standard organic chemistry glassware. Red bromine gas escaped from the glassware and burned several of us. (1321)
Other cases include: 1477

Bunsen Burner

1037. In a high school lab a student was "drying" his beaker with gas from the gas jet. He had observed the advanced chemistry students drying glassware with an air jet and gas and air were all the same to him. The gas build up was ignited by a flame from another burner in the room. (1089)

1038. A student was going about lighting a Bunsen burner. Her partner turned on the gas after the match was lit. As she lit the burner flames occurred at the bottom of the burner. (Tubing at the bottom of the burner had been loosened.) She immediately turned off the gas.

Our class motto: "When in doubt, turn off the gas!" This could have been very dangerous. The students should have only lab materials at the lab stations; no pocketbooks, lunches, unnecessary papers. (1117)

1039. In 1980 I was a first year graduate student employed as a teaching assistant, instructing a freshman biology lab. The very first class required the students to use a Bunsen burner in practicing aseptic techniques (sterilizing needles/loops, etc.) and making various slides of micro organisms.

I asked the students to light their Bunsen burners. I had previously placed one burner at each station. I was suddenly made aware of a roaring sound and a stream of fire. One student had ignited the gas outlet valve. He did not know what a burner was. This taught me not to take anything for granted when explaining to students. I now try to be very specific and explain the steps in great detail. (1216)


1040. In a high school chemistry I class around 1980 an experiment of chromatography of chlorophyll pigments was being conducted. One pair of students were working on the chromatography lab and were heating a solution of methanol in which leaf material is placed. They were working near a slightly opened window using a Bunsen burner, ring stand and ring support and water bath set up. Both were wearing goggles and aprons.

About six feet away another pair of students, not wearing goggles, were working on the same lab but were further along in the experiment. Their procedure required the use of several solvents including petroleum ether. They were preparing the solvent chamber and the TLC plate. Apparently the ether was left open. Suddenly a fireball erupted severely burning the students. The ether container and the solvent chamber both burned.

Since this accident Bunsen burners are no longer used to heat alcohol and ether is not used. (1226)

1041. Students were heating a chemical when the gas tube to the Bunsen burner came off. The flame transferred to the gas supply. It happened during a practical exam so everyone was in silence. From the stir this caused the girl in the front row turned, saw what was happening and turned off the gas at the source. (1313)

1042. A student in a chemistry lab was entering data in a lab book. A Bunsen burner was on the lab table burning. The student reached across the table to pick up a piece of equipment and burned his arm in the flame from the burner. (1381)
1043. A student was attempting to light a Bunsen burner in a high school chemistry class. As the gas ignited the flame shot higher than he thought it would and burned his eyebrows and the front of his hair. The student had neglected to regulate the gas flow at the Bunsen burner prior to lightening it. Since the gas flow was at a maximum the resulting flame was dangerously high.

Students should be taught proper lab techniques. (1420)


1044. A Bunsen burner was left on all night. The next day a person turned on the light switch. From it a tiny spark ignited the gas which has built up in the room. (1451)
1045. A student turned on the gas jet and properly lit a Bunsen burner. The gas jet fell off the wall connection (loosened by another student the previous period) and a flame shot out of the wall. The gas shut-off valve was located behind a panel under a desk. A Phillips screwdriver was needed to open the panel. (1455)
1046. While demonstrating a lab that required lighting a Bunsen burner. I adjusted the burner as per safety instructions. I continued to talk to the class as I opened the gas tap and held the lit match to the burner. However, I had opened the wrong tap. Eventually the gas lit and the ball of fire singed my hair. They called me "flash" for the rest of that year. (1491)
Other cases include: 1076, 1102, 1121, 1164, 1169, 1170, 1171, 1211, 1219, 1228, 1233, 1234, 1261, 1264, 1339, 1340, 1395, 1412, 1490




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