March 18, 1997

APS TECHNICAL UPDATE - No. 12

Subject: Installing Equipment on the Roof of a Radiation Enclosure and/or Installing a Ladder to Reach Such Equipment

For additional information contact:

 

Julie Cross - User Technical Interface
jox@aps.anl.gov
Telephone - 630.252.0592

Updated: October 4, 2007

Installing Equipment on the Roof of a Radiation Enclosure
and/or Installing a Ladder to Reach Such Equipment

Some CATs are considering the installation of equipment on the roofs of radiation enclosures on their beamlines. These CATs may also be considering the installation of a ladder to enable personnel to reach the equipment. Many questions have recently been asked on this topic. Before these questions can be addressed, the CAT's requirements must be understood in detail. It is very important to recognize that each CAT's situation is different and specific data are needed to analyze the programmatic and safety requirements for each installation.

The questions listed below are designed to generate the data required for the analysis. They were compiled with the following considerations in mind:

Use of ladders: There are significant hazards associated with the use of vertical ladders to access the roofs of enclosures; in general, vertical ladders are inappropriate if the climber is carrying anything, including notebooks, tools, or equipment. Alternatives include scissor lifts and movable stairs that become fixed when loaded with the weight of a person.

Working at elevations: Fall protection needs to be provided for any person working on the roof of an enclosure.

ALARA practices: In the standard specifications of the shielding for the enclosures, a low rate of occupancy on the enclosure roofs was assumed, and the thickness of the lead in the roof panels was reduced accordingly.

Loads on station roofs: Designs for ladders, gangways, railings, etc., must meet applicable safety standards. Also, the floor space around the enclosure must be adequate for the installation.

Please submit answers to the following questions to Kevin Randall before developing plans for the installation of equipment on the roof of an enclosure on your beamline and/or the attachment of a ladder to an enclosure.

  1. Is there a definite justification for the need to install the equipment on the roof of the radiation enclosure? If so, provide a one-page written justification.
  2. If the equipment cannot be installed on the roof of the enclosure, what are the alternatives?
  3. What is the weight of the equipment to be installed?
  4. What is the electric power requirement to operate the equipment?
  5. What other utilities (DI water, chilled water, pressurized air, etc.) are required to operate the equipment?
  6. Does an exhaust vent need to be connected to the equipment?
  7. Where will the discharge from the exhaust go?
  8. Does the exhaust contain gases that are considered noxious?
  9. Is the equipment connected to the beamline EPS?
  10. What degree of vibration and/or noise will be generated when the equipment is in operation?
  11. How often will access to the equipment be needed?
  12. What is the typical duration of each access period?
  13. How many persons will be on the roof of the enclosure simultaneously to use/maintain the equipment?
  14. What tools and other items will need to be carried to the roof of the enclosure to use/maintain the equipment?
  15. How long a ladder is required to take the tools to the roof of the enclosure?
  16. Is there adequate room around the enclosure to accommodate an installed ladder plus the surrounding space required for easy access?
  17. What training will be required to use/maintain the equipment?
  18. What mechanism will be used to control access to the ladder and/or the equipment by untrained people?
  19. What records will need to be kept on access to the installed equipment to facilitate safety oversight?
  20. Does the approved CAT Safety Document adequately cover the hazards that may result from this installation?

The above questions may generate additional questions, which should also be addressed. When answers to all these questions have been provided, the APS (and, as appropriate, ANL) staff, along with the CAT members, will be able to evaluate the engineering and safety requirements for the installation. This evaluation will lead to a proper definition of the equipment, the access requirements, the installation plan, and the training and record-keeping requirements before the installation begins.

Updated: October 4, 2007