See also Cleanliness Core Facility Inspection Report Safety Inspection


Last updated March 1, 2018

Chemicals | Fire Safety and Emergencies | Fume Hood | Electron Microscope Settings | Liquid Nitrogen | Radiation | Examination of Infectious Materials


Within the facility there are a variety of chemicals available for the purpose of specimen preparation. Chemicals in the laboratory include organic solvents, acids, bases, and volatile/combustible substances. Individuals using any of the chemicals within the facility are expected to exercise general chemical safety.


  • Treat every chemical as if it were hazardous.
  • Use required safety equipment specific to any chemical being handled.
  • Make sure all chemical containers are appropriately labeled with their contents.
  • Do not create a waste chemical bottle or container.  Only lab staff are authorized to create such a container.
  • Do not mix nitric acid with solvents unless you have been specifically trained in that procedure.
  • Do not return chemicals to reagent bottles.
  • Comply with fire regulations concerning storage quantities, types of approved containers and cabinets, proper labeling, and so on. If uncertain about regulations, contact the facility coordinator.
  • Use volatile and flammable compounds only in a fume hood. Procedures that produce aerosols should also be performed in a hood to prevent inhalation of hazardous material.
  • Dispose of waste and broken glassware in proper containers.
  • Clean up spills immediately in the manner specified by the MSDS sheet corresponding to the spilled substance. If the substance is unknown, contact facility staff.
  • Do not store food in laboratories.

to top

Fire Safety and Emergencies

The Michigan Technological University emergency guide applies for all facilities on campus. In case of a fire or another emergency, refer to the University EMERGENCY GUIDE.

NOTE: The ACMAL facility has switched from a halon system to the use of water for fire suppression.

The emergency phone number is 911.

to top

Fume Hood

A fume hood is an enclosure designed for the handling of volatile and flammable chemicals. The primary function is creating a flow of air from the laboratory, through the adjustable face (sash) of the fume hood, and to the outside of the building. This air flow removes any volatile or toxic fumes away from the user’s breathing area, creating a safer working environment. The sash also gives added protection by separating the user from aerosols, spills, and small explosions.


  • Before using the fume hood for the containment of toxic or volatile substances, always checking whether the hood is functioning properly.
  • Determine where the sash should be positioned for optimum containment using the hood survey sticker.
  • Ensure that the fume hood vents are open and free from obstruction.
  • Place the chemical container deep enough within the hood to ensure that no toxic fumes escape.
  • Extend only hands and arms into the hood.
  • Do not lean on the sash.
  • Clean the fume hood after use.
  • Do not use the fume hood for storage.

to top

ELECTRON Microscope Settings

As a result of the sophistication of electron microscopes, the user interfaces of these machines are often complex. Many of the available controls are used for calibration or maintenance and do not usually require adjustment during regular use. For this reason, this facility expects that users do not attempt to make setting adjustments using controls with which they are unfamiliar.


  • If an irregular setting is required for imaging, contact facility staff for assistance.
  • After each use, return the instrument to its default settings.
  • If the user is unable to return an instrument to its regular settings, contact facility staff.


to top

Liquid Nitrogen

Properties of LN2

At atmospheric pressure, the temperature of liquid nitrogen is around 77.3 K = -196ºC = -320ºF. This relatively low temperature can result in damage to human skin or eyes upon contact. Also, LN2 can become oxygen enriched by condensing and dissolving oxygen, which may cause ordinarily noncombustible materials to burn rapidly.

Nitrogen gas is colorless and odorless. On vaporization, LN­2 expands by a factor of 700; one liter of liquid nitrogen becomes 24.6 cubic feet of nitrogen gas. This expansion can cause an inappropriately sealed or damaged container of LN2 to explode and/or displace the oxygen in the room. This may lead to suffocation without warning.


  • When handling liquid nitrogen, always wear eye protection, cryo-gloves, and appropriate leg and foot protection.
  • When transferring liquid nitrogen, use only approved unsealed containers, assure that the container lid is always loose, and carry the container with both hands.
  • Do not leave liquid nitrogen stored in an unsealed container unattended.
  • Never dip an open hollow vessel into liquid nitrogen; it may spurt liquid.
  • Never use in a small poorly ventilated room, and never dispose of liquid nitrogen by pouring it on the floor or down the sink.
  • When storing liquid nitrogen, use only approved sealed containers.

to top



ACMAL is equipped with a variety of x-ray analysis tools which create ionizing radiation. In itself ionizing radiation is dangerous; however the devices within the lab that produce radiation all have internal radiation shielding which allows for their operation without the need for personal radiation protection. These include all of the SEMs, TEMs, X-ray Diffraction (XRD) instruments, and the X-ray Fluorescence (XRF) unit. All such equipment must be registered with the State of Michigan, with provides periodic inspections to ensure no radiation is leaked from the instruments.

Nevertheless, users are expected to follow proper safety precautions at all times and to alert technical staff to any unusual instrument behavior.


SEMs can produce x-ray radiation as a result of high energy electrons interacting with the metal in the column. The amount of x-ray radiation produced depends largely upon the accelerating voltage applied to the electron beam. It will be greater for accelerating voltages attainable with the TEM (>100 kV). All facility SEMs have internal shielding and interlock systems, however, which protect the user from x-ray radiation. Michigan state law requires that these systems be inspected and maintained regularly, so that users need not take additional precautions during operation.


Both XRD and XRF utilize x-ray (ionizing) radiation for probing materials. For this reason these machines have extensive shielding and interlock systems in order to protect the user from possible radiation leaks. Since the x-ray source is present when the specimen is inserted–and as an added precaution–XRD and XRF users are required by law to wear x-ray badges. It is important to know that there have never been any exposures outside of safe limits within this facility.

Contact Ed Laitila to get an x-ray badge before entering the XRD or XRF facilities.


  • Wear your assigned x-ray badge during XRD and XRF while in the lab
  • Never bypass safety interlock circuits
  • Never remove auxiliary shielding
  • Be familiar with the procedure to be carried out. If you are unfamiliar, contact facility staff
  • Report any unusual instrument behavior to facility staff

to top

Examination of Infectious Materials

As a policy, infectious and potentially infectious materials cannot be brought into the EM facility. The specimens should be fixed with glutaraldehyde or other appropriate fixative that will inactivate the infectious material before the specimens are taken to the EM facility. In addition to inactivating the infectious material, the fixative also helps preserve the ultrastructure of the material for study. Depending on the feature of interest, specimens could be fixed in solution or directly on the grid after they have dried.

Osmium tetroxide is another common fixative used for TEM. It not only fixes and stabilizes the material, but also provides contrast so that the specimen is more easily seen. Osmium tetroxide is often used in combination with glutaraldehyde.


See also CICF safety.
to top