Safety

Anyone wishing to make use of any of the EPR spectrometers MUST undergo the appropriate training session with a member of the EPR staff before using the instruments. 

Samples 

•  Be extremely careful when you handle sealed glass samples that are rapidly heated or cooled. The rapid cooling of some samples may result in the formation of a solid bolus in the sample tube that may make the tube prone to explosive rupture. 
•  Educate yourself about the temperature at which chemicals evaporate. When a sample gets close to the temperature at which it evaporates, it may quickly become volatile. 
•  In general, the safety threat posed by flying glass and violently escaping gases and liquids should not be underestimated. 
• Wear safety glasses, face masks, and other protective clothing whenever there is any risk of spillage, breakage, or explosion. Protective shields should also be employed when there is any risk of explosion. 
• Never leave unlabeled equipment and EPR tubes in the EPR laboratory. 

Oxygen Depletion

• A Dräger oxygen depletion alarm system is in place in CÆSR to alert users to unsafe conditions. Alarms begin at 19.0 % O2(g) and increase intensity as depletion increase.

• Liquid Helium and liquid Nitrogen expand more than 700 times in volume and lead to depletion of oxygen. 
• Local gas flows from pressurize vessels or from drying tubes, or in close proximity to liquid N2 dewars may result in undetectable local depletion, be aware of your surroundings. 
• Room venting systems, such as windows may be used to refresh the laboratory room air, but never enter a room if the O2(g) percentage drops below 16% -- close-off N2 lines to CÆSR and wait. 
• A usage-specific Risk Assessment is required for N2 gas in CÆSR. 

Magnetic fields 

There are specific safety hazards associated with use of the EPR instruments that relate primarily to the presence of intense stray magnetic fields in the vicinity of the instruments which may affect or interfere with: 

•  heart pacemakers 
•  medical implants 
•  magnetic bank or ID cards 
•  watches (non-LCD) 

As a consequence, specific rules exist regarding access to the EPR laboratories: 

•  Anyone with a heart pacemaker must not go beyond the magnetic field hazard warning signs posted in the CRL and will not be allowed access to any EPR laboratory.
•  Anyone with a medical implant must seek approval from the Director of EPR Spectroscopy before entering any EPR laboratory or making direct use of any EPR spectrometer. 
•  No laboratory coats are to be worn in the EPR laboratories. 
•  No metal objects are to be taken into EPR laboratories. 

Microwaves 

• Do not have an open waveguide when the microwave power is on. 
• Switch the bridge to standby when you remove or change EPR cavities. 
• Never look down an open waveguide when there is microwave power. The eyes are very susceptible to damage from microwaves. 

Lasers 

For Information regarding the Laser facilities, you must read the LS1 form and sign the LS4 form including some evidence of having completed training for Prof. Chris Timmel or Dr. Will Myers to sign.  You should have a discussion with Dr. Kevin Henbest.  (To access LS1 and LS4 forms you must be on computer connected to the Oxford network, right-click on link and choose Save Link As.)  Here is a link for the LASER safety video, requiring Single Sign-On (link).