Lessons Learned


Lessons Learned Archives

Phenol Chemical Burn
Phenol exposure from pipette		 Polyacrylamide Gel
Eye exposure to gel		 Nitric & Sulfuric Acid     Acid splash to face Hydrochloric Acid Spill
Acid bottle slipped from grip		 Mercury Spill
Broken thermometer
Thermal Burn
Burn from hotplate		 UV Exposure
Exposure from a UV lamp		 Microtome Cut
Injury from microtome blade		 Glass Bottle Burst
Laceration from shrapnel		 Cryogen Vial Explosion
Injury from Eppendorf tube
Waste Bottle Fire
Mixing solid and liquid waste		 Parr Bomb Explosion Overpressurized parr bomb

Phenol-Chloroform Chemical Burn

What happened?

A researcher was discarding an Eppendorf pipette tip filled with buffer solution containing phenol/chloroform/isoamyl alcohol (DNA extraction) when a drop of fell onto their leg. Absorption was felt through their pants and onto their skin. The researcher was wearing nitrile gloves but no lab coat or any form of eye protection. The researcher went to the restroom and removed their contaminated clothing. Another member of the lab provided the researcher with a nonionic detergent (Nonidet P40) for treatment to place directly on their skin. No additional medical attention was sought. The incident was called into the EH&S general line.

Phenol Hazards

  • Toxic and highly corrosive.
  • Causes severe skin burns and eye damage.
  • Rapidly absorbed through skin.
  • When combined with chloroform, penetration of skin, clothing, and most glove materials is enhanced.

Injury

No injuries were sustained. This incident is considered a “near miss” because the lack of proper PPE use resulted in a risk of injury to the skin or eyes.

Contributing Factors

  • Lack of proper PPE.

Corrective Actions

  • Phenol exposure should be treated with a liquid low molecular weight polyethylene glycol (PEG 300 or 400).
  • SOP for phenol must be reviewed annually by all applicable lab members.
  • Make EH&S’ Phenol Safety Fact Sheet and SDS available to personnel to read, review and understand.
  • Distribute EH&S’ Eye Protection Fact Sheet.
  • DPS shall be contacted in the event of an exposure.

Quick Tips

  • Use splash goggles in phenol-chloroform extraction procedures. Note: Safety glasses are NOT appropriate for splash hazards — chemical splash goggles must be worn.
  • Work with phenol should be performed in a fume hood, when possible. A fume hood must be employed if phenol is heated, sprayed, powdered, or used in more than very small quantities.

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Polyacrylamide Gel Eye Exposure

What happened?

A researcher was using Polyacrylamide gel electrophoresis (PAGE) to analyze DNA fractions. After running the gel, a procedure was used to extract the DNA into a liquid phase. The procedure called for a liquid/gel mixture to be forced through a filter using a 1 mL syringe. When the researcher attempted this, the filter blew off the end of the syringe and gel flew into their eye.

The researcher was wearing nitrile gloves but no eye protection or lab coat at the time of incident. They tried to use the eyewash stations at two different locations inside the lab but stated that the water started to flood the floor. They then rinsed their eyes in the restroom for 5 minutes and sought medical attention at the Engemann Student Health Center. Another member of the lab notified EH&S of the incident.

Corrective Actions

Quick Tips

  • Most safety shower/eyewash stations are designed without drains beneath them to ensure hazardous materials do not enter the sewage system. Thus, safety shower/eyewash stations should be used regardless of any possible flooding that may occur.

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Nitric & Sulfuric Acid Splash

What happened?

Researcher #1 was returning a bottle of concentrated nitric acid (16 Molar (M); ~70% by mass) and a bottle of diluted sulfuric acid, 3 M, to the stock room. The bottles were placed in a plastic tray along with other chemicals on the countertop next to the sink. Researcher #1 grabbed both bottles from the tray intending to return them to the shelf. Both bottles slipped from their hands, fell to the floor and broke splashing acid on their face. Researcher #1 tried to use the eye wash station located near the sink, however the water did not dispense due to the handle being lifted instead of depressed. They then ran out of the stock room to a nearby lab to use the safety shower/eyewash station. The researcher showered for approximately 2-3 minutes before rinsing their eyes for another 15 minutes.

Researcher #1 was wearing nitrile gloves and a flame-resistant lab coat during the chemical transfer. However, they were not wearing any form of eye protection and were wearing sandals exposing their ankles and feet. While Researcher #1 was using the safety shower/eyewash station, Researcher #2 reported the incident to the lab manager and the lab manager contacted DPS.

Acid Hazards

  • Concentrated nitric acid is highly oxidizing and corrosive.
  • Nitric acid vapor is an irritant and harmful to the respiratory system.
  • Diluted sulfuric acid is corrosive.

Injury

Researcher #1 sustained superficial burns to the face and scalp.

Contributing Factors

  • Lack of proper PPE.
  • Improper use of safety shower/eyewash station.

Corrective Actions

Quick Tips

  • Most eyewash stations require depressing the handle to operate as opposed to lifting it up.
  • Use a wheeled cart when substantial quantities of hazardous materials need to be moved.
  • When transferring bottles place one hand on bottle and one hand below to brace.

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Hydrochloric Acid Spill

What happened?

Researcher #1 was working on a lab bench transferring concentrated hydrochloric acid (HCl), 37%, into an empty glass bottle in an effort to make a 1M Tris-HCl buffer solution. Researcher #1 was holding the glass receiving bottle in their hand over the floor during the transfer. Following completion of the transfer, the receiving glass bottle slipped out of Researcher #1’s hand and shattered on the floor spilling its contents. Researcher #1 was wearing nitrile gloves and a fluid resistant barrier lab coat. No eye protection was worn and the researcher’s legs were not fully covered by clothing. No personal exposure occurred.

Researcher #1 and Researcher #2 evacuated the lab to call EH&S. Researcher #3 did not feel comfortable leaving the spilled HCl on the floor without doing anything to mitigate the hazards. Researcher #3 attempted to neutralize the spill with 4N sodium hydroxide. Upon contact with the HCl, there was a release of vapor followed by a strong odor. Researcher #3 then evacuated the lab. Researcher #3 was wearing nitrile gloves and a flame-resistant treated cotton lab coat, but no eye protection during the attempted cleanup. The EH&S Hazardous Materials team responded, neutralized the area and cleaned up the spill.

Hazards

  • Concentrated hydrochloric acid is corrosive to skin and eyes, an irritant to the respiratory system, and toxic if inhaled in significant quantity.
  • Sodium hydroxide is extremely corrosive to eyes.
  • Physical hazard from sharps produced from broken glass bottle.

Injury

This incident did not result in injury; it is considered a “near miss” because poor PPE practice resulted in definite risk of injury, especially to the eyes.

Contributing Factors

  • Receiving vessel was held over the floor instead of being placed on a counter inside of a fume hood.
  • Lab personnel were not aware of the proper procedures for spill cleanup.

Corrective Actions

Quick Tips

  • Lab personnel should not work directly out of large stock bottles. Personnel should decant a small working volume into a small bottle.
  • When diluting concentrated acid, you should add the acid to water, not the inverse.

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Mercury Spill

What happened?

A mercury thermometer broke when it fell out of an incubator onto the floor. Researcher #1 didn’t notice any contents in the thermometer and moved it to the benchtop within the lab. Researcher #1 left the broken thermometer on a desk near the incubator with the intention of notifying the Lab Manager. The Lab Manager was not immediately available and Researcher #1 eventually forgot to inform them.

No personal exposure occurred at time of incident. DPS and EH&S were not notified. The researcher was wearing a lab coat and nitrile gloves but no eye protection.

One week later, Researcher #2 noticed the broken thermometer on the benchtop in the lab. They were aware that this thermometer housed mercury when intact. Researcher #2 and the Lab Manager then visually inspected the floor in front of the incubator to locate any mercury droplets. The two Researchers then proceeded to use a glass plate to gather as many droplets as they could visibly identify.

During cleanup, both were wearing nitrile gloves and a lab coat but no eye protection. No personal exposure occurred at time of incident. Following cleanup, the Lab Manager contacted DPS to report the spill.

Mercury Hazards

Mercury rapidly emits highly toxic vapor at room temperature. Breathing the vapor for a prolonged time may result in cumulative chronic poising with severe health effects.

Injury

This incident did not result in injury.

Contributing Factors

All lab personnel were not aware of the significant hazards of mercury.

Corrective Actions

  • For mercury spills of any quantity, immediately restrict access to the area, evacuate, and notify DPS. Check all PPE that may have come in contact with a mercury spill, including shoes. If contaminated, items should be bagged and labelled as hazardous mercury waste.
  • Do NOT attempt to clean a mercury spill as this may result in breaking the mercury into smaller droplets, furthering its spread.
  • Use of elemental mercury thermometers is strongly discouraged in all instances. Replace with digital and/or ethanol-based products if possible.

Quick Tips

Do not wear metal hand and wrist jewelry when handling mercury metal, mercury compounds. Contact of mercury with metal jewelry may result in immediate adsorption of mercury to form an amalgam, resulting in the jewelry becoming a toxic health hazard.

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Thermal Burn

What happened?

A researcher was heating water in a glass vial using a hotplate in a fume hood. They observed the buildup of condensation in the vial due to evaporation, however, they felt that the hot plate was not heating enough. The researcher placed their gloved hand on the hot plate and did not feel the heat. They then removed their glove and placed their finger on it, which led to a burn.

The researcher immediately reported the burn to their supervisor and placed their affected finger under cold water. They sought medical attention at the Engemann Student Health Center and were told that the burn was superficial. They were not administered first aid or medication. The incident was not called in to DPS or the general EH&S line.

Injury

This incident did not result in serious injury.

Corrective Actions

  • Hot surfaces shall not be touched without the use of thermal gloves.
  • Report all injuries to DPS.

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UV Exposure

What happened?

Researcher #1 and #2 were analyzing their photos from a gel experiment using a Molecular Imager. Realizing that there was a problem with the images, they opened the instrument without turning off the UV lamps within. Researchers were exposed to UV radiation for several minutes while they were troubleshooting. Neither researcher was wearing PPE at the time of the incident.

No immediate affects from the UV radiation exposure were felt. However, both Researchers started feeling symptoms later that evening, including skin redness and peeling, severe pain and itchiness in the eyes, blurry vision, nasal discharge and discomfort. Researcher #1 went to the ER the same night, while Researcher #2 went to the ER the next day and both were informed that they were experiencing symptoms consistent with UV radiation exposure.

The researchers informed their PI of the incident the next day. The PI reported the incident to the general EH&S line.

UV Hazards

  • Eye exposure from UV in the actinic range (200-315 nm) may inflame or burn the cornea resulting in photokeratitis and/or conjunctivitis.
    • Photokeratitis is distinguished by a feeling of sand in the eyes.
    • Actinic conjunctivitis causes redness, swelling, and eye irritation.
  • Other eye effects of UV in the actinic range are a sever sensitivity to bright light or the production of tears, both can last for several days.
  • Skin exposure from UV in the actinic range can produce symptoms similar to a severe sunburn including redness (erythema), swelling, blistering, pain, and peeling of the skin.
  • Chronic exposure to UV may increase risk of skin cancer and cataracts.
  • The International Agency for Research of Cancer (IARC) has classified UV as a Group I human carcinogen.

Injury

Researcher #1 and #2 sustained temporary eye and skin irritation and burns.

Contributing Factors

  • Lack of proper PPE.
  • Lack of Molecular Imager SOP.
  • Lack of appropriate signage indicating hazards.

Corrective Actions

  • When working with UV radiation (both long and short wavelength), eye, face, and hand protection is required.
  • Label hazardous instruments with clear warning signs.

Quick Tips

  • Do not cut gels on instrument dock.
  • Ensure UV lamps are turned off prior to opening instrumentation.

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Microtome Cut

What happened?

A researcher was working with mouse tissue fixed with paraformaldehyde (PFA) in a frozen paraffin block prepped for slicing with a microtome. They placed the frozen block on the instrument and removed the microtome blade from the dispenser inserting it into the instrument. They found they needed to adjust the frozen block for accurate cutting of their sample but did not remove the blade nor set the lock on the rotary wheel while making the adjustments. The researcher’s finger slipped and was nicked on the edge of the blade.

They were not exposed to any additional hazardous material. All appropriate PPE was worn. DPS was not notified.

Microtome Hazard

A microtome has a sharp blade used to cut thin slices for histological analysis.

Injury

Researcher sustained a laceration to the proximal portion of the left middle finger.

Contributing Factor

Researcher did not follow proper procedure when adjusting the frozen paraffin block in the microtome.

Corrective Actions

  • Generate an SOP detailing the safe and proper use of a microtome.
  • Report all injuries to DPS.

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Pressurized Bottle Burst

What happened?

Researcher #1 was setting up a reaction in a pressurized Fischer-Porter bottle under nitrogen and demonstrating the experimental setup to Researcher #2. The experimental process involved addition of reactants to the pressure bottle, flush of in-house nitrogen gas, and heating in an oil bath. While setting up the experiment, Researcher #1 was adjusting the clamp on the manifold when the nitrogen pressure spiked to 120 psi. The bottle exploded downwards into the oil bath. The heat application step had not been started at the time of the explosion.

Researcher #1 informed their PI of the incident and subsequently visited the Engemann Student Health Center. Lab personnel did not call DPS or EH&S to report the incident, however a manager’s report was filed.

Researcher #1 was wearing safety glasses but no lab coat; there was not a blast shield in place. Researcher #2 was wearing a lab coat, and safety glasses.

High Pressure Hazards

  • Risk of explosion.
  • Glass pressure vessels may randomly fail below their rated pressure, especially if the glass surface is microscopically scratched or etched.

Injury

Researcher #1 sustained minor cuts on arm.

Contributing Factors

  • Lack of blast shield.
  • Lack of proper PPE.

Corrective Actions

  • Proper PPE must be worn, including lab coats, when working with hazardous materials.
  • Lab personnel shall post signage warning others of ongoing experiments with high pressure reactors.
  • Report all injuries to DPS.

Quick Tips

A fume hood sash does not provide the same level of protection as a blast shield and should not be used in lieu of one.

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Cryogen Vial Explosion

What happened?

A researcher was working alone in the lab when attempting to open a box containing cryovials and Eppendorf tubes stored in liquid nitrogen. The Eppendorf tubes began exploding and the researcher was hit in the jaw.

The researcher’s jaw started to bleed. They called DPS, rinsed the wound, and used the lab’s first aid kit. They then visited the Engemann Student Health Center and subsequently emailed their PI and lab personnel to inform them of the incident.

The researcher was not wearing any safety glasses and there was no face shield available in the lab.

Liquid Nitrogen Hazards

  • Direct contact with liquid nitrogen, cold vapor, or cold metal can freeze tissue and cause frostbite/cold burns.
  • Boiling of liquid nitrogen produces large volumes of inert gas which can asphyxiate by displacement of oxygen.
  •  Boiling of liquid nitrogen in a closed vessel creates high pressure which is likely to explosively burst the vessel.

Injury

Researcher sustained a minor flap wound on right jaw.

Contributing Factors

  • Another member of the lab used Eppendorf tubes instead of cryovials. Eppendorf tubes do not reliably seal when cold and may fill with liquid nitrogen, causing them to burst on warming.
  • Researcher did not use safety glasses/goggles plus face shield, which is the required PPE for removing cryovials from liquid nitrogen storage.

Corrective Actions

  • All lab personnel must be trained on the proper safety standards for working with liquid nitrogen.
  • All lab personnel must be trained to use correct vials for storage at liquid nitrogen temperatures, and to be aware of the explosion hazard when vials are removed from cold storage.
  • Cryogen gloves, eye protection, and lab coat are required when working with liquid nitrogen.
    • Please reference the Cryogens & Dry Ice Fact Sheet for more information.
    • Face shield is required when removing vials from liquid nitrogen storage.
  • Develop an SOP for working with cryogens.

Quick Tips

Eppendorf tubes are not suitable for storing samples in liquid nitrogen. Vials specifically rated by the manufacturer for liquid nitrogen temperatures shall be used. Vials should be stored in the gas phase and not under the surface of liquid nitrogen, to reduce the probability of liquid nitrogen leaking in to the vials. Be aware that even with these precautions, vials will occasionally explode after removal from liquid nitrogen freezers.

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Waste Bottle Fire

What happened?

Researcher #1 discovered a sealed glass globe labeled dry heptane that had been left by a previous lab member. They did not immediately notice the grey powder at the bottom of the clear, colorless liquid, and began pouring the liquid into the open safety funnel of a large waste container (mixed chlorinated and non-chlorinated liquid waste). The liquid almost immediately caught fire upon touching the waste funnel. Researcher #1 immediately closed the lid on the funnel, causing the flame to go out, and went to notify the lab’s safety officer. The waste container was not in a fume hood, but was on the floor in the open lab, standing in secondary containment.

Before Researcher #1 and the safety officer could return to the waste container, Researcher #2 opened the funnel lid and poured in two NMR tubes of waste solvent. One tube contained deuteroacetone (flammable) and one contained deuterochloroform (non-flammable). Researcher #2 reported seeing a “tiny red glow”, sparks, and a small flame, and immediately closed the lid of the funnel in response.

Researcher #2 was worried that the flame may travel down into the body of the waste container. In an effort to prevent that from happening, they unscrewed the funnel from the waste container while Researcher #3 got a fire extinguisher from a nearby wall. By the time the funnel was removed, the flame was out so the extinguisher was not used.

After the incident, Researcher #2’s throat was hurting and they became concerned that they may have been exposed to irritants potentially produced by the combustion (e.g. sodium oxide/hydroxide smoke, which can be produced by burning sodium). They were checked at the Engemann Student Health Center as a precaution but no injury was found.

Gloves, safety glasses, and FR lab coats were worn by all personnel in the lab at the time of incident. DPS and EH&S were not notified.

Hazards

  • Heptane is a flammable hydrocarbon liquid.
  • The powder, which contained some lumps, may have been a reactive metal hydride or an alkali metal.

Injury

This incident did not result in injury. Although no injuries were found, this incident is considered a “near miss” because it could have easily resulted in burn injuries.

Contributing Factors

  • Improperly labeled glass globe.
  • Improper chemical waste segregation.

Corrective Actions

  • Everything, except substances actively in use, should be labelled. Even vessels of minimal hazard materials require labelling with the identity of the contents, as this minimizes the difficulty of clean-up in case of spillage.
  • It is strongly recommended that PIs implement and enforce lab rules that students clean up their work space before leaving the university, including providing labelling and appropriate storage for all samples which the PI wishes to retain.

Quick Tips

  • Labeling improves housekeeping and lab efficiency by preventing an accumulation of unlabeled “orphan” containers.
  • Halogenated and non-halogenated waste should be segregated.

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Parr Bomb Explosion

What happened?

Researcher #1 set up an experiment with acetic acid, polyethylene, and a catalyst in a common type stainless steel pressure vessel known as a “Parr bomb”. The vessel was then pressurized with a moderate pressure of oxygen and heated in a thermostatically controlled oil bath. There was a magnetic stir bar inside the bomb and a stir plate underneath the oil bath. The experiment was set up behind a blast shield inside a fume hood. The Parr bomb was fitted with a pressure gauge and bursting disk, designed to pop out at a high pressure, but was set to be well below the pressure at which the body of the bomb would be in danger of failing. After setting up the experiment, Researcher #1 left the lab to let the experiment run. Later in the day Researcher #2 reported hearing a loud bang and reported it to Researcher #1. The lab was unoccupied at the time of the incident.

Researcher #1 returned to the lab to find the oil bath smoking and turned off the heat. They realized that the emergency pressure relief bursting disk had blown out, which had apparently shot upwards and cracked the roof panel of the fume hood into two pieces. The fume hood sash was also cracked and a removable access panel of the fume hood was dislodged. Silicone oil used for heating was splashed in the hood and on the blast shield. The bomb, oil bath, stir plate, and blast shield all remained in position. Researcher #1 cleaned up the debris and hazardous materials and contacted their PI to inform them of the incident. The PI emailed Lab Safety to report the incident and EH&S responded to investigate. DPS was not notified.

Hazards

If the chemical potential energy is sufficient to significantly increase the temperature of the Parr bomb plus contents, then there is potential for thermal runaway.

Injury

This incident did not result in injury.

Contributing Factors

Scale-up of experimental parameters without proper calculations to assess the possible degree of danger.

Corrective Actions

  • Parr bomb should be fitted with a bursting disk designed to open at a relatively low pressure (e.g. 50 atm).
  • A shield or cage should be provided to retain the disk if it pops out, so it does not become a projectile and cause damage.
  • Consider fitting an additional spring loaded pressure relief valve operating at lower pressure than the bursting disk.
  • To prevent overheating, use a second thermocouple in the oil bath connected to a cut-out circuit which cuts power to the system if the temperature rises past a setpoint that is suitably above the normal operating temperature.
  • Calculations should be performed to determine the chemical potential energy (enthalpy) contained in the oxygen-fuel mixture inside the bomb.
  • DPS should be contacted before contacting PIs or managers.

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