Prepare for your visit

Before starting work at CHESS, it must be determined whether Hazardous Materials are involved. If such materials are to be brought, specific information must be provided and internal procedures followed before beamtime is granted. These procedures involve two parts: (1) tasks that must be completed well in advance of arrival and (2) tasks to be completed once the hazardous material arrives at CHESS. Upon submission of your proposal, any hazardous or potentially hazardous, explosive, toxic, radioactive materials, or radiation-producing sources, must be declared and submitted in writing for review by the CHESS Safety Committee. The following information is required for EACH MATERIAL.

1. Name of material (one form for each material)
2. MSDS Sheet (MSDS CHESS inventory)
3. Description of substance (powder, liquid, solution, etc.)
4. Quantity (mass, concentration)
5. Means of containment (sealed in glass capillaries, flasks, encapsulated)
6. Toxicity routes (ingestion, subcutaneous, absorption, inhalation)
7. Procedures in case of emergency (clean-up, evacuation, emergency first-aid)

Include safety precautions your home institution requires or suggests in the proper handling of the material and what actions should be taken in the event of an emergency.

All proposals that are declared hazardous will be assigned a Safety Officer (a member of the CHESS Safety Committee) to check-in the group when they arrive at CHESS and check-out the group when they leave. The Safety Officer will ensure that all equipment is safe to use, will go over detailed safety information related to the experiment, and will arrange for the disposal of any hazardous waste. Contact the CHESS Safety Committee at chess-safety@cornell.edu with any questions regarding hazardous materials and safety concerns.

Users are encouraged to bring the smallest amounts possible of hazardous materials to CHESS.

Please do not bring the hazardous materials into the building before you meet with a member of our Safety Committee. The operator on duty will put you in contact with this person during check-in. In certain instances, a preliminary inspection will be required before the material is allowed into the building.

An experiment is non-hazardous if:

• The protein or other material being studied is not toxic (or infectious) for humans.
• No heavy atom compounds are used (intrinsic metals such as the iron in hemoglobin are not considered as heavy atoms, nor are metal foil reference samples).
• Heavy atom compounds are present only in pre-derivatized crystals.
• The crystals may be mounted in capillaries, frozen, or contained in solutions free of the heavy atom compound.
• As long as you stay within this category, CHESS does not need to be informed if you bring samples other than those listed on the proposal.

An experiment may be hazardous if:

• Heavy atom compounds are present outside of crystals. In this case, you must supply CHESS with a Heavy Atom Compounds Declaration, listing the type and amount of each compound. The Safety Committee will then classify the experiment as hazardous or not, using the following guidelines:
  • For solutions:
    The experiment is considered non-hazardous if the total quantity of each heavy atom compound is no more than 1/50 the LD-50 for a 50 kg animal or 0.01 mM if the LD-50 is not available. LD-50's, when known, are provided on Material Safety Data Sheets. If multiple values are given, the most appropriate one (in terms of method of administration and similarity of test animal to humans) is used. If the total quantity is above these values but below half the LD-50 for a 50 kg animal, or 0.25 mM if the LD-50 is not available, the experiment is hazardous but may be carried out at CHESS. Quantities greater than half the LD-50 or 0.25 mM may not be brought to CHESS.
  • For dry material:
    Reference samples for multi-wavelength anomalous diffraction (MAD) experiments are non-hazardous if they are well-sealed (e.g. between two layers of Kapton tape) before being brought to CHESS. For loose material, the same limits on total quantity as for solutions are used.

An experiment is hazardous if:

• The protein or other material is toxic or infectious to humans. In this case, you must supply CHESS with a Hazardous Materials Declaration, and Viral Materials Declaration, if appropriate. Extra time will be needed to review and process this documentation.

If in doubt, contact station scientists for clarification.

Procedures to be used with BL-2 viruses adhere to Cornell EH&S biosafety guidelines.

Specific procedures for working with crystals at CHESS are delineated below:

• Crystals of viruses must be brought to CHESS in a double-sealed, properly labeled container, as required by the DOT for transport of infectious materials.
  • Crystallization trays or sealed capillaries containing unfrozen crystals must be surrounded with absorbent material and sealed within a sturdy outer container.
  • Frozen crystals must be contained in vials enclosed in a Dewar or dry shipper.
• Virus crystals must be kept at the station, though they may be stored/mounted in another room if necessary (e.g., the cold room or the chemistry lab). The cognizant Safety Officer must verify the nature and amount of viral materials brought by the user.
• Biohazard warning signs must be placed on the doors of all rooms in which crystals will be stored or used. Access to areas in which crystals will be handled will be restricted to the investigators, the CHESS operators, and members of the CHESS and LNS Safety Committees. If other personnel require access to the area, the crystals must be first contained beforehand, unless already mounted on the oscillation camera.
• Table and bench tops in the storage and mounting area must be covered with plastic-backed absorbent paper, which is soft enough so that any dropped capillaries or crystals will not bounce off and absorbent enough to soak up any spills. When crystals are actually being manipulated, it is recommended to cover the immediate area with absorbent paper wetted with disinfectant, so that any dropped crystal will be inactivated.
• In the hutch, any surfaces on which a capillary or crystal might fall must be covered with plastic-backed absorbent paper. If frozen crystals are being used, any equipment which could be contaminated in case of cryosystem failure must be protected by a plastic shield which can be removed and decontaminated. Freezing of crystals directly into the cold stream is permitted, provided coverage of surfaces and equipment is adequate to catch any viral material that could be dropped in the mounting process. A germicidal lamp must be available in the hutch, in case decontamination is needed.
• Mounting of crystals into capillaries, or freezing of crystals into cryogens, must be performed in the room where the crystals are stored.
• Crystals frozen in the storage and mounting area must be transported to the hutch in a container of liquid nitrogen that is enclosed in an outer container to catch spills.
• Any spills or dropped samples must be limited to an absorbent paper-covered surface or the interior of a container. The users must clean up the spill using bleach or other suitable disinfectant to decontaminate any places where viral material might have landed. Broken capillaries are to be placed in a "sharps" container for later disposal. In the unlikely case of a spill that involves unprotected surfaces or equipment or in which an aerosol may have been produced, the cognizant Safety Officer must be consulted to determine appropriate decontamination procedures. A reminder of procedures to follow in case of spills must be posted in the crystal mounting and storage area and in the hutch.
• Used capillaries must be placed in a "sharps" container. Used frozen crystals must be either disposed of in a biohazard bag (if the loop is to be salvaged, use disinfectant solution to wash a crystal out of a cryoloop into a small container and put the container in the bag) or stored in a Dewar, still frozen, for later use.
• At the completion of their experiments, the users must roll up the absorbent paper and dispose of it in a biohazard bag. All surfaces which could have been contaminated by virus must be washed with a suitable disinfectant (e.g., bleach or alcohol). The materials used for this cleanup must also be disposed of in the biohazard bag. Biohazard bags and sharps containers of used capillaries must be placed in a biohazard container (provided by CHESS) for later pickup by Cornell EH&S. The cognizant Safety Officer must verify that no biohazardous materials have been left at CHESS, except in the biohazard container.

• General MX data collection strategy
• Tables of resolution and cell dimensions vs. crystal-detector distance
• HKL2000 Site Definition Files
• XDS Input Files
• Remote MX data collection

• Data collection tutorial

• Crystal centering video

• Puck loading video