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Subsections


Experiment policies

Beamtime shifts schedule

The beamtime starts at 3:00 pm of the first day allocated to the experiment and end at 11:00 am of the last day; exceptions: Accelerator Physics may move the end time to 6 am.

User responsibilities

Users collecting data on-site are responsible for the following:

  • If applicable, reading and complying with the policies regarding use of heavy metals, propane, compressed gases and liquid nitrogen use.
  • Knowing and following all applicable safety protocols.
  • Posting the proper safety protocols and signs required for their experiment.
  • Cleaning up the beamline and lab areas before their run has ended.

Both on-site and remote users are responsible for:

  • Insuring that one experimenter who has attended the beamline orientation participates in the experiment at all times.
  • Contacting SSRL staff in case of a problem.
  • Backing up data before their run has ended.
  • Reporting missing or malfunctioning equipment.

Users should not attempt:

  • Making repairs or realigning beamline optics.
  • Removing covers or unplugging detectors and other electrical equipment.
  • Rebooting computers.
  • Using SSRL computers other than those provided at the assigned beamline.

Off-line use of computer resources

  • Only run one job per blcpu machine during the user run.
  • There are no restrictions during machine physics and shutdown periods.

Use of the SAM robot for sorting samples between cassettes and/or unipucks

Blu-Ice provides an interface for moving samples between cassettes and/or uni-pucks. This facility is available to SSRL users during their scheduled beamtime. The following policies apply:

  • Sample sorting is considered to be part of the experiment and should be completed by the end of the scheduled beamtime.
  • This service is not available during beamline maintenance periods, accelerator physics or SPEAR shutdowns.
  • All the SSRL cassettes or unipucks used to move samples must be supplied by the user, and mounted on the beamline robot dewar at the start of the experiment or during normal working hours.
  • Staff may not be called at off hours or on weekends to load a cassette in the dewar for sample sorting.


Heavy metal use

The following protocol is required for on-site preparation of heavy atom solutions or crystal soaking. It does not apply to use of frozen pre-soaked crystals.

  • Post the "Caution: Heavy Metal Solutions" sign in the working area prior to usage.
  • Ensure that containers of solutions containing heavy atoms are clearly labeled, identifying contents, owner's name, contact telephone number and date.
  • Heavy metal solutions can only be made up in one of the Biotechnology Laboratories, and safety glasses and gloves shall be worn. Containers of volatile heavy metal solutions shall be opened in a working hood in one of these laboratories. The area in the hood must be lined with absorbent material.
  • Quantities of less than 1 ml of solution, containing less than 0.1 M of heavy metals, may be removed from the Biotechnology laboratory in labeled and tightly sealed containers and transported to the sample preparation area at the beamline for soaking crystals.
  • Soaking crystals at the beamline shall be performed in the Heavy Metal containment tray; absolutely no exceptions. The tray is located next to the computer table. Contact support staff if you can not locate the containment tray. The tray should be lined with absorbent material.
  • Spills outside the containment tray shall be wiped up immediately with absorbent material (present at the beamline toolborad). The SSRL Safety Office must be notified immediately of any heavy metal spill that escapes the containment tray. Please contact the Beamline Duty Operator for this to occur.
  • Any liquid or solid waste, including gloves, absorbent material and other contaminated material should be bagged, clearly labeled and disposed of as hazardous waste. The SSRL Safety Office should be contacted for proper disposal.
  • All heavy atom solutions shall be returned to the user's home laboratory at the finish of the experiment.


Propane and ethane use

The following protocol is required for bottles/canisters of propane or ethane gas used at SSRL for the purpose of flash-cooling samples. The use of prefrozen samples containing propane or ethane does not require any special protocol.

  • The "Caution Flammable Gas" sign must be posted at the work area prior to usage. Only small bottles/canisters are allowed at SSRL (lecture bottles). The propane/ethane bottle shall be set up for dispensing in a clear open space.

  • The bottle must be secured to the table.

  • No electrical appliances or ignition sources, such as a wax melter, microscope, etc. are allowed to be in this area.

  • The amount of liquid propane/ethane dispensed for flash cooling should not exceed 10 mL.

  • After dispensing the gas, ensure the bottle valve is firmly closed.

  • Empty gas bottles shall be returned to the experimenter's home institution.


Liquid nitrogen use

This section describes hazards and proper handling procedures for work with liquid nitrogen

Skin and eye frostbite burns

Direct contact with liquid nitrogen, metal or other material that is in contact with liquid nitrogen or cold nitrogen gas can cause freezing of exposed tissue.

  • Follow all documented procedures for a given task and any additional instructions that may be posted at the work site.

  • Wear the appropriate Personal Protection Equipment (PPE) appropriate for the task.


Table 1: Required PPE for handling Liquid Nitrogen
Safety Glasses Cryogenic Gloves Goggles or Face Shield Long Pants without cuffs or Apron Closed-toe shoes Insulated tool handles
Fill dewar with close-loop transfer line X X
Fill dewar with open flow delivery line X X X X
Dewar to dewar transfer X X X X
Removing/storing items in dewars X X X X
Transporting open dewars holding less than 0.5 L X X
Disposing of liquid nitrogen by pouring on ground X X X X
Disposing of liquid nitrogen by bubbling warm nitrogen gas X X
Manipulating protein crystals in dewars X X
Transporting dewars or tanks with lids or closed valves
Disposing of liquid nitrogen by evaporation

Asphyxiation

In confined areas, there is a risk of asphyxiation by displacement of oxygen. Do not use liquid nitrogen in a confined space unless the maximum allowable amount of liquid nitrogen has been posted by the SSRL Safety Officer or if the room is equipped with an oxygen deficiency (OD) alarm.

  • All experiment hutches are equipped with OD alarms. Immediately exit the hutch if the alarm sounds. If the OD alarm sounds when you are outside the hutch, do not enter the hutch.Do not open the door until the alarm has stopped.

  • The experimental floor is also equipped with oxygen alarms, which can activate if, e.g. a liquid nitrogen line ruptures or leaks. If the experimental floor OD alarm sounds, treat it like am emergency alarm: exit the building through the nearest exit and do not re-enter until the duty operator indicates that it is safe to do so.

  • Cold rooms in general are not equipped with OD alarms. Do not exceed the posted amount of liquid nitrogen allowable in the confined space. If there is no posting, do not bring liquid nitrogen into the confined space.

Instructions for liquid nitrogen disposal

  • Use a warm nitrogen bubbler to evaporate liquid nitrogen when possible.

  • Small amounts of liquid nitrogen (less than 0.5 Liters) can be poured carefully in an open area on the floor.

  • Larger amounts must be poured in an open area outside the building.


Compressed gas experiments

The following policies apply for work at the SSRL involving gases delivered in compressed gas cylinders (CGC):

  • Requests to work with CGC must be indicated the Beam Time Request Form (typically submitted three times per year). To make a request after the form has been submitted, contact the SSRL User Office.

  • Standard instructions and safety protocols are to be applied when using the SSRL pressurization cells:

    1. The SSRL pressure cells may only be used as specified in the instructions.

    2. The CGC must be secured at all times during the experiment.

    3. Only support staff are allowed to replace an empty CGC.

  • The following experiments require specific safety protocols to be developed by SSRL staff; this requires at least a 1 month lead time before the beam time:

    1. Experiments using CGC directly purchased and shipped by the user.

    2. Experiments involving flammable, toxic or corrosive gases (e.g. O2, CO).

    3. Experiments involving gases conducted in the cold room or other confined space.

    For case 2 and 3, complete the Hazards From available from the User Research Administration Database is required for cases 2 and 3.

  • Xenon and Krypton CGC are supplied by the SSRL SMB group. Other gases may be purchased through SSRL by filling the specialty gas purchase form. Setting up an SSRL account is required for purchasing items through the SSRL.