HANDLING OF X-RAY TUBES IN RELATION TO THE HAZARDS OF BERYLLIUM.
 
 

(beryllium: beware and be aware)




INTRODUCTION.

Be advised that beryllium as present in X-ray tubes is recognized as a hazardous substance and may create hazards to persons when not handled and disposed of properly.
To avoid any such hazards the material must be handled with great care and always in accordance with the instructions below in connection with the installation, operation and servicing of the equipment.
Disposal of beryllium should further be handled in accordance with local laws, regulations and requirements.
 

OCCURRENCE, PROPERTIES AND USE.

Beryllium is a lightweight, strong metal and, compared with other metals, hardly absorbs X-rays.
It is present in X-ray tubes only in "massive" form: the windows.
This guarantees minimal absorption of the radiation generated inside the tube.
 

HAZARDS.

National and international health organisations have classified beryllium and its compounds (with the exception of aluminium beryllium silicates) as follows:
 

Classification Description

R49  Carcinogen cat. 2. May cause cancer by inhalation

R26  Very toxic by inhalation

R25  Toxic if swallowed

R48/23  Toxic: danger of serious damage to health by prolonged exposure through inhalation.

R36/37/38  Irritating to eyes, respiratory system and skin.

R43  May cause sensitisation by skin contact.

The dangers to health which can arise from beryllium are mainly due to inhaling the substance.
Inhaling dust or fumes containing beryllium may cause serious, chronic lung disease called Chronic Beryllium Disease (CBD). Soluble salts of beryllium may present additional ingestive, eye and skin hazards
So, when working with beryllium metal, compounds and alloys it is important to distinguish between the massive form and dust or fumes: if beryllium can enter the body as dust, fume or soluble salt it can damage your health.
Beryllium metal (in massive form) is not easily absorbed by the human digestive system and there is no evidence that it is poisonous when swallowed.
The hazard "Toxic if swallowed" applies to certain soluble beryllium salts and is therefore added to the classification. Large pieces of beryllium are unlikely to cause any ill effects.
Normal handling of beryllium does not cause skin effects. Cuts should be properly cleaned and dressed; embedded material (swarf, splinters) should be removed.
 

RISKS.

Beryllium and beryllium containing materials present health hazards by the inhalation route only.
Soluble salts of beryllium may present additional ingestive, eye and skin hazards.
Normal use of an X-ray tube does not present danger to the health as it will not generate beryllium dust or fumes.
As no indications have been found that corrosion products (which could be soluble beryllium salts) spread there will be no danger when standard industrial hygiene rules are applied when handling tubes.
 
 

The presence of Be in X-ray tubes does not present any danger to the operator whatsoever, providing standard industrial hygiene is applied during installation, operation, service and removal. 

REFERENCES.

Brush Wellman: Material Safety Data Sheet (no. M10) Beryllium Solid
H.S.E./COSHH: Health & Safety Executive, Control of Substances Hazardous to Health (Regulations)
Guidance Note EH13: Beryllium, health and safety precautions.
If you need any additional information on handling X-ray tubes with respect to the hazards of beryllium please contact your supplier.



INSTRUCTIONS FOR HANDLING TUBES

When handling tubes observe the following rules:

A. General.

  1. Do not manipulate (machine, weld, grind, saw, polish etc.) the beryllium window(s) in any way that may cause dust or fumes.
  2. Check the beryllium window(s) whenever possible for corrosion (corrosion usually indicates incorrect circumstances under which the tube has been operated). Correct the circumstances that have caused the corrosion, but do not remove the corrosion.
  3. Put the window protection on the tube whenever possible.
  4. Do not touch the beryllium window(s) at all.
  5. Do not eat, drink or smoke while handling tubes.
  6. Wash hands afterwards.
B. Installation.
  1. Unpack the tube without touching the window(s). Keep the plastic bag and the window protection at hand, you may need them later.
  2. Do not remove the window protection until really necessary.
  3. If there is dust on the window(s) remove it with a soft brush or with a flow of dry air.

  4. Do NOT use human breath as this contains moisture.
  5. Ensure that the windows do not become contaminated with water, dirt, grease and dust etc.

  6. Besides the possible formation of dangerous soluble Be-salts it will most likely cause corrosion that will decrease the life time of the tube.
  7. Check, and if necessary clean and dry, the environment in which the tube will be put into operation.
C. Operation.
  1. Check the beryllium window(s) whenever possible for corrosion, but do not remove the corrosion.
  2. Verify the functional performance of the tube regularly.
  3. Ensure that both tube and environment stay clean and dry.
D: Service.
  1. Remove the tube without touching the window(s).
  2. Take care not to spill water on the window(s). If this occurs remove the water by absorbing it with a soft tissue.
  3. Check the beryllium window(s) for corrosion (corrosion usually indicates incorrect circumstances under which the tube has been operated). Find and correct the circumstances that have caused the corrosion, but do not remove the corrosion.
  4. Check whether the deposit on the window(s) could have been caused by sample rests spilled on the window.
  5. When no other cause for deposits can be established it should be assumed that white (light brownish) spots on the window consist of BeO. Avoid contact.
  6. White deposit around the window(s) does not usually consist of BeO. However, to be on the safe side, avoid contact.
  7. If there is deposit on the window(s) but there are no indications

  8. - that the performance of the tube has become unacceptable
    - that the performance will become unacceptable in the near future
    - that the deposit will cause a bad vacuum inside the tube
    - that the deposit will spread around
    put the window protection back into place (if this is no objection to further activities) and perform all necessary service activities but do not violate the "general" rules.
  9. Put the tube back into operation taking into account all relevant "installation" rules.
E. Removal / storage.
  1. Remove the tube from the system in accordance with rules D1/D7.
  2. When the tube is not put back into operation all the water should be removed from the cooling circuit(s) of the tube. Please use pressurized air (reversed flow direction) long enough to ensure complete removal.
  3. Ensure that the outside of the tube is dry.
  4. Put the window protection device back into place, put the tube into its original plastic bag and close the bag.


In case the tube is returned to the supplier "FOR DISPOSAL ONLY" the window area may be covered with adhesive tape to prevent the deposit from spreading.
This should not be done with tubes that will be returned as a warranty claim or for investigation and repair.