Guidance for Industry and FDA 
Staff 
 
 
Hospital Bed System Dimensional 
and Assessment Guidance to 
Reduce Entrapment  
 
 
Document issued on: March 10, 2006 
 
The draft of this document was issued on August 30, 2004.  
 
 
 
For questions regarding this document contact Jay A. Rachlin, Office of  Communication, 
Education, and Radiation Programs, 301-796-5722, jay.rachlin@fda.hhs.gov or Joan Ferlo 
Todd, Office of Surveillance and Biometrics, 301-796-6079, joan.todd@fda.hhs.gov. 
 
 
 
 U.S. Department of Health and Human Services 
Food and Drug Administration 
Center for Devices and Radiological Health 
 
Division of Device User Programs and Systems Analysis (HFZ-230) 
Office of Communication, Education, and Radiation Programs 
                
Division of Postmarket Surveillance (HFZ-520) 
Office of Surveillance and Biometrics 
 
 
 
 
  Contains Nonbinding Recommendations 
 
 
Preface 
 
 
Public Comment 
 
Written comments and suggestions may be submitted at any time for Agency consideration to 
the Division of Dockets Management, Food and Drug Administration, 5630 Fishers Lane, 
Room 1061, (HFA-305), Rockville, MD, 20852.  Alternatively, electronic comments may be 
submitted to http://www.fda.gov/dockets/ecomments.  When submitting comments, please 
refer to Docket No. 2004D-0343.  Comments may not be acted upon by the Agency until the 
document is next revised or updated. 
 
 
Additional Copies 
 
Additional copies are available from the Internet at http://www.fda.gov/cdrh/beds, or you 
may either send a fax request to 301-847-8149 to receive a hard copy of the document, or 
send an e-mail request to DSMICA@CDRH.FDA.GOV to request hard or electronic copy.  
Please use the document number 1537 to identify the guidance you are requesting.   Contains Nonbinding Recommendations 
 
 
Table of Contents  
 
Introduction..........................................................................................................................................................1 
The Least Burdensome Approach.......................................................................................................................2 
Background...........................................................................................................................................................2 
Standards and Future Harmonization.................................................................................................................4 
Organization of this Guidance.............................................................................................................................5 
Scope......................................................................................................................................................................5 
Articulation........................................................................................................................................................7 
Legacy Beds......................................................................................................................................................7 
Exclusions..........................................................................................................................................................8 
Reporting an Entrapment Adverse Event..........................................................................................................9 
Key Body Parts at Risk......................................................................................................................................10 
Head.................................................................................................................................................................10 
Neck.................................................................................................................................................................11 
Chest................................................................................................................................................................12 
Potential Zones of Entrapment.........................................................................................................................13 
A Retrospective Study of Entrapment Reports to FDA..................................................................................14 
Dimensional Limits for Identified Entrapment Zones 1-4..............................................................................15 
Zone 1  Within the Rail.................................................................................................................................15 
Zone 2  Under the Rail, Between the Rail Supports or Next to a Single Rail Support..................................16 
Zone 3  Between the Rail and the Mattress...................................................................................................17 
Zone 4  Under the Rail at the Ends of the Rail..............................................................................................18 
Zone 5  Between Split Bed Rails...................................................................................................................19 
Zone 6  Between the End of the Rail and the Side Edge of the Head or Foot Board.....................................19 
Zone 7  Between the Head or Foot Board and the End of the Mattress.........................................................20 
APPENDIX A:  List of Hospital Bed Safety Workgroup (HBSW) Participating Organizations...............22 
APPENDIX B:  Additional Information and Kit Information.......................................................................23 
APPENDIX C:  References for National and International Entrapment Standards...................................24 
APPENDIX D:  Anthropometric References...................................................................................................25 
APPENDIX E:  Drawings of Potential Entrapment in Hospital Beds...........................................................27 
APPENDIX F:  HBSW Dimensional Test Methods for Bed Systems............................................................28 
 
  Contains Nonbinding Recommendations 
 
 
Guidance for Industry and FDA Staff 
 
  
 
Hospital Bed System Dimensional  
and Assessment Guidance to  
Reduce Entrapment  
 
 
 
This guidance represents the Food and Drug Administration's (FDA's) current thinking 
on this topic.  It does not create or confer any rights for or on any person and does not 
operate to bind FDA or the public.  You can use an alternative approach if the approach 
satisfies the requirements of the applicable statutes and regulations.  If you want to discuss 
an alternative approach, contact the FDA staff responsible for implementing this 
guidance.  If you cannot identify the appropriate FDA staff, call the appropriate number 
listed on the title page of this guidance.  
 
 
Introduction 
 
This guidance provides recommendations relating to hospital beds1 and hospital bed 
accessories.  The guidance provides recommendations intended to reduce life-threatening 
entrapments associated with hospital bed systems.2  It characterizes the body parts at risk for 
entrapment, identifies the locations of hospital bed openings that are potential entrapment 
areas, and recommends dimensional criteria for these devices.   
 
Manufacturers may use this guidance when designing new beds to help ensure compliance 
with applicable FDA regulations such as the Quality System regulation3, to provide adequate 
labeling and instructions for use, and to assist in ensuring that their devices are safe when 
used as labeled.  FDA encourages manufacturers to provide information to medical device 
                                                 
1 The terms medical bed and hospital bed are used interchangeably throughout this 
document and include adult medical beds with siderails.  See discussion in Scope, page 5. 
 
2 As used in this guidance, hospital bed system encompasses the bed frame and its 
components, including the mattress, bed side rails, head and foot board, and any accessories 
added to the bed. 
 
3 Title 21, Code of Federal Regulations, Part 820  Quality System regulation. 
 
1  Contains Nonbinding Recommendations 
 
 
distributors, clinicians, patients and families regarding mattress dimensions, compatible 
components, and issues of entrapment.  In addition, the recommendations in this guidance 
may be useful in evaluating and reducing the entrapment risk presented by hospital beds that 
have been placed into use, also known as legacy beds. 
 
Not all patients are at risk for an entrapment, and not all hospital beds pose a risk of 
entrapment.  We suggest that facilities and manufacturers determine the level of risk for 
entrapment and take steps to mitigate the risk. Evaluating the dimensional limits of the gaps 
in hospital beds is one component of an overall assessment and mitigation strategy to reduce 
entrapment.  As a result, healthcare facilities may use this guidance as part of a bed safety 
program to help identify entrapment risks that may exist with current hospital bed systems.  
Other educational documents are available to assist health care facilities in making decisions 
towards the goal of achieving a safe and comfortable sleeping environment for their patients.     
 
FDA's guidance documents, including this guidance, do not establish legally enforceable 
responsibilities.  Instead, guidances describe the Agency's current thinking on a topic and 
should be viewed only as recommendations, unless specific regulatory or statutory 
requirements are cited.  The use of the word should in Agency guidances means that 
something is suggested or recommended, but not required. 
 
 
The Least Burdensome Approach 
 
We believe we should consider the least burdensome approach in all areas of medical device 
regulation.  This guidance reflects our careful review of the relevant scientific and legal 
requirements and what we believe is the least burdensome way for you to comply with those 
requirements.  However, if you believe that an alternative approach would be less 
burdensome, please contact us so we can consider your point of view.  You may send your 
written comments to the contact person listed in the preface to this guidance or to the CDRH 
Ombudsman.  Comprehensive information on CDRH's Ombudsman, including ways to 
contact him, can be found on the Internet at http://www.fda.gov/cdrh/ombudsman/. 
 
  
Background 
 
For 20 years, FDA has received reports4,5 in which vulnerable patients6,7 have become 
entrapped in hospital beds while undergoing care and treatment in health care facilities. The 
                                                 
4 Ferlo Todd  J, Ruhl C, Gross T P, Injury and Death Associated with Hospital Bed Side 
Rails:  Reports to the U.S. Food and Drug Administration from 1985 to 1995. American 
Journal of Public Health 1997; 87:1675-1677. 
 
5 Hospital Bed Safety Workgroup A Guide to Bed Safety, http://www.fda.gov/cdrh/beds/.  
 
6 U. S. Food and Drug Administration.  FDA Safety Alert: Entrapment Hazards with Hospital 
Bed Side Rails (August 23, 1995), U.S. Department of Health and Human Services.  
2  Contains Nonbinding Recommendations 
 
 
term "entrapment" describes an event in which a patient/resident is caught, trapped, or 
entangled in the space in or about the bed rail8, mattress, or hospital bed frame.  Patient 
entrapments may result in deaths and serious injuries.   
 
FDA received approximately 691 entrapment reports over a period of 21 years from January 
1, 1985, to January 1, 20069.  In these reports, 413 people died, 120 were injured, and 158 
were near-miss events with no serious injury as a result of intervention.  These entrapment 
events have occurred in openings within the bed rails, between the bed rails and mattresses, 
under bed rails, between split rails, and between the bed rails and head or foot boards.  The 
population most vulnerable to entrapment are elderly patients and residents, especially those 
who are frail, confused, restless, or who have uncontrolled body movement.  Entrapments 
have occurred in a variety of patient care settings, including hospitals, nursing homes, and 
private homes.  Long-term care facilities reported the majority of the entrapments. 
 
In response to continued reports of patient entrapment, the FDA, in partnership with the U.S. 
Department of Veterans Affairs, Health Canadas Medical Devices Bureau and 
representatives from national health care organizations and provider groups, patient advocacy 
groups, and medical bed and equipment manufacturers, formed a working group in 1999 
known as the Hospital Bed Safety Workgroup (HBSW).  Appendix A contains a list of 
HBSW participating organizations.  The HBSW also worked in cooperation with the Joint 
Commission on Accreditation of Healthcare Organizations, the U.S. Centers for Medicare 
                                                                                                                                                       
 
7 Vulnerable patients are defined in A Guide to Bed Safety, developed by the Hospital 
Bed Safety Workgroup (described on pages 3-4), as: Patients who have problems with 
memory, sleeping, incontinence, pain, uncontrolled body movement or who get out of bed 
and walk unsafely without assistance.  These patients most often have been frail, elderly or 
confused." 
 
8 FDA uses the term bed rails frequently throughout this document.  Commonly used 
synonymous terms are side rails, bed side rails, grab bars and safety rails.  Bed rails are rigid 
bars that are attached to the bed and are available in a variety of sizes and configurations 
from full length to half, one-quarter, and one-eighth length and are used as restraints, 
reminders, or as assistive devices.  An historical review can be found in Braun & Capezuti, 
"The Legal and Medial Aspects of Physical Restraints and Bed Side rails and Their 
Relationship to Falls and Fall-Related Injuries in Nursing Homes, DePaul Journal of Health 
Care Law, vol. 4, Fall 2000. 
 
9 FDA acknowledges several limitations of these adverse event report data.  First, many 
adverse events may not be reported to the FDA, thus the true number of adverse events may 
be unknown.  Second, the number of reported events does not represent incident rates for a 
given problem in the absence of a defined denominatorthe number of individuals at risk for 
a given adverse event.  Finally, many reports lack a complete and detailed description of the 
adverse event or are not verified.  Despite these limitations, adverse event reports can suggest 
a profile of the areas or locations on a hospital bed that present a risk of entrapment, as well 
as the parts of the body that are at risk of entrapment. 
 
3  Contains Nonbinding Recommendations 
 
 
and Medicaid Services, and the U.S. Consumer Product Safety Commission to improve 
patient safety associated with the use of hospital beds.  
 
The HBSW identified 7 potential entrapment zones (See Potential Zones of Entrapment, 
Page 13) in hospital beds. The workgroup then developed (1) educational materials regarding 
entrapment associated with hospital beds, (2) clinical practice guidelines to reduce the 
occurrence of patient entrapment, (3) evidence-based dimensional guidelines for hospital 
beds, (4) test tools and methods to assess gaps in hospital bed systems, and (5) information to 
assist in mitigating entrapment risks in currently used hospital beds.  See Appendix B for 
information on the availability of these materials. 
 
Consistent with 21 CFR 10.115(f), the HBSW submitted to FDA recommendations for 
hospital bed dimensional criteria for consideration as an FDA guidance document.  Members 
of the HBSW have developed procedures for measuring and assessing gaps in hospital bed 
systems in accordance with these criteria.  Healthcare personnel, through participation in 
HBSW testing, validated the test methods and tool.  The FDA has considered these HBSW 
recommendations in preparing this guidance.   
Standards and Future Harmonization 
The International Electrotechnical Commission (IEC) issued an internationally recognized 
standard that applies to a certain segment of the products addressed in this guidance, products 
labeled as powered hospital beds.  This standard is the IEC 60601-2-38, Amendment 110.  
The current IEC standard recognizes that the bed frame, deck, and rails are the major 
elements involved in entrapment, but does not include the mattress as a contributor or 
mitigator and sets dimensions for new beds only.  The standard also does not address safety 
issues associated with the use of non-electric hospital beds or the use of hospital beds in the 
home or in long-term care settings.  The IEC standard is currently undergoing revision and 
will likely undergo significant change prior to its expected publication in 2007/2008.  The 
recommendations in this FDA Guidance are similar to the IEC standard for some entrapment 
zones, but differ in other zones to include consideration of the mattress as part of the 
entrapment risk.  The IEC test methods are not readily applicable for use by health care 
providers and are written primarily for test labs.  Upon completion of the revised 
international bed standard, FDA will consider whether harmonization of the FDA guidance 
and the IEC standard is appropriate.  See Appendix C for a list of National and International 
Entrapment Standards. 
 
                                                 
10 International Electrotechnical Commission  (IEC) 60601-2-38, Amendment 1, 1999 
Medical Electrical Equipment  Part 2-38: Particular Requirements for the Safety of 
Electrically-Operated Hospital Beds. 
4  Contains Nonbinding Recommendations 
 
 
Organization of this Guidance 
 
This guidance: 
 
  identifies key parts of the body at risk for entrapment  
 
  describes potential entrapment areas or zones 
 
  recommends maximum and minimum dimensional limits of gaps or openings in 
hospital bed systems 
 
  provides a scientific basis for the dimensional limits derived from a review of 
international anthropometric data, a review of historical entrapment data, and a 
retrospective study to verify the proposed dimensional limits  
 
  provides information about reporting entrapment adverse events  
 
  provides a copy of the HBSW test methods for assessing gaps or openings in hospital 
bed systems 
 
  provides information about obtaining other HBSW documents and instructional 
materials     
  
 
 
Scope 
 
The goal of the FDA Hospital Bed System Dimensional and Assessment Guidance to Reduce 
Entrapment is to reduce potential life-threatening entrapments associated with hospital bed 
systems. Because hospital bed systems that are primarily intended for one type of care setting 
can be moved into other care settings, the recommendations in this guidance may be 
appropriate for hospital beds regardless of the healthcare setting.  The dimensional limits in 
this guidance may not reduce entrapments in all populations, e.g. pediatrics and 
developmentally disabled people.  See the narrative below in the exclusions section. 
 
FDA uses the term hospital bed in this guidance to refer to a variety of medical devices 
that are classified as beds.  FDA regulations classify hospital beds as Class I and Class II 
devices (see Table 1).  These devices are used for patients in acute care, long-term care, or 
home care settings.  FDA considers stretchers that are used for extended stay in health care 
facilities (because they are used like hospital beds) as hospital beds for purposes of this 
guidance.  As stated above, the term hospital bed system used throughout this document 
encompasses the bed frame and its components, including the mattress, bed side rails, head 
and foot board, and any accessories added to the bed.  Bed rails (see footnote 8), also called 
side rails, may be an integral part of the bed frame or they may be removable and at times 
are used either as a restraint, a reminder or an assistive device.  Bed rails may consist of one 
5  Contains Nonbinding Recommendations 
 
 
full-length rail per side or one or more, shorter rails per side, may be a fixed height or 
adjustable in height, and may move as the head or foot sections of the bed are raised or 
lowered. 
 
 
This guidance provides recommendations related to devices in the following table (Table 1). 
Class II devices are subject to design controls under the Quality System regulation.  For those 
beds in class II, we recommend that manufacturers consider the recommendations in this 
guidance when developing their design controls.  The recommendations in this guidance may 
also assist manufacturers of all devices listed in Table 1 below in manufacturing hospital 
beds that will minimize the risk for patient entrapment. 
 
Table 1: Bed Systems Covered under this Guidance 
Product Code  CFR Section  Classification Name  Class  510(k) Exempt
FMR  880.6785  Manual patient transfer device   I  Yes 
FNJ  880.5120  Manual adjustable hospital bed  I  Yes 
FNK  880.5110  Hydraulic adjustable hospital bed  I  Yes 
FNL  880.5100  AC-powered adjustable hospital bed  II  Yes 
FPO  880.6910  Wheeled stretcher*  II  Yes 
IKZ  890.5225  Powered patient rotation bed  II  Yes 
ILK  890.5150  Powered patient transport*  II  No 
INK  890.3690  Powered wheeled stretcher*  II  No 
INY  890.5180  Manual patient rotation bed  I  Yes 
IOQ  890.5170  Powered flotation therapy bed  II  Yes 
*When labeled for extended-stay use 
 
The recommendations in this guidance may also be useful in evaluating and reducing the risk 
of entrapment presented by the devices listed in Table 1 that have already been manufactured 
and installed (legacy beds).  FDA recognizes that legacy beds have the potential for 
dimensional change over time through wear and tear or substitution of new mattresses and 
other components not contemplated in the original bed system.  Because of these factors, 
FDA does not intend to take enforcement actions for failure to submit reports of corrections 
and removals under 21 CFR Part 806 for actions taken in response to this guidance that 
correct or improve hospital beds currently in use or held as inventory.   However, 
manufacturers and importers should create and maintain records of these corrections and 
removals in accordance with 21 CFR Part 806.  
 
Some states may have adopted special requirements for the design of hospital beds.  For 
example, New York has adopted more stringent dimensional limits for hospital beds and twin 
beds used for developmentally disabled people.11  The dimensions used in the FDA guidance 
are not intended to replace state law requirements that may exist.  Moreover, some hospital 
beds excluded from the scope of the recommendations in this guidance may still be subject to 
dimensional limits under state laws. 
                                                 
11 Schatz, William M., PT,  Bed Safety Consulting, Inc., Comment #C2 to Docket #2004 D-
0343, Draft Guidance for Industry and FDA Staff; Hospital Bed System Dimensional 
Guidance to Reduce Entrapment, November 10, 2004. 
6  Contains Nonbinding Recommendations 
 
 
 
   
Articulation 
The movement of the bed deck is known as articulation. FDA recognizes that articulation of 
the bed introduces complex geometries that make applying the dimensional criteria to reduce 
entrapment difficult.  Presently, the dimensional recommendations in this guidance apply to 
hospital beds in the flat deck position and rails in the fully raised position, except where 
noted.  FDA recognizes that patient care also occurs while the bed is articulated and some 
articulated positions may pose a risk of entrapment.  The Agency will continue to gather data 
and consider other approaches for assessing gaps in articulated beds in the future.  We 
recommend that patient assessment procedures be used to assess the risk of entrapment when 
clinical care is provided in an articulated position. 
Legacy Beds 
The issue of patient entrapment in hospital beds is complex and affects manufacturers, 
healthcare practitioners and facilities, medical equipment suppliers, home health agencies, 
patients, and caregivers.  Many beds currently in use may no longer have the original 
mattress or bed rails, and may present an entrapment hazard by increasing or creating gaps or 
spaces between various components of the bed system.  The recommendations in this 
guidance therefore apply to most hospital beds, including legacy beds in various settings 
where health care is provided. As described above, a new hospital bed becomes a legacy 
bed as soon as it is placed into use.   
 
Reducing the risk of entrapment involves a multi-faceted approach that includes bed design, 
clinical assessment and monitoring, as well as meeting patient, resident, and family needs for 
vulnerable patients in most health care settings - hospitals, long term care facilities, and at 
home.  Therefore, comprehensive bed safety programs in these settings will likely involve 
input from manufacturers as well as facility staff.  Recognizing that not all hospital beds 
present a risk of entrapment, and that this risk may vary depending on the patient, FDA 
encourages manufacturers and facilities to work together to develop bed safety programs to 
evaluate and, if needed, mitigate entrapment risk.   
 
When evaluating the safe use of a hospital bed, component or accessory, manufacturers and 
caregivers should recognize that the risk for entrapment may increase if a hospital bed system 
is used for purposes, or used in a care setting, not intended by the manufacturer.  Evaluating 
the dimensional limits of gaps in hospital beds may be one component of a bed safety 
program which includes a comprehensive plan for patient and bed assessment.  Bed safety 
programs may also include plans for the reassessment of hospital bed systems. Reassessment 
may be appropriate when (1) there is reason to believe that some components are worn (e.g., 
rails wobble, rails have been damaged, mattresses are softer) and could cause increased 
spaces within the bed system, (2) when accessories such as mattress overlays or positioning 
poles are added or removed, or (3) when components of the bed system are changed or 
replaced (e.g., new bed rails or mattresses). 
 
7  Contains Nonbinding Recommendations 
 
 
FDA recommends that healthcare facilities conduct a risk-benefit analysis to ensure that steps 
taken to mitigate the risk of entrapment do not create different, unintended risks or reduce 
clinical benefits available to patients using legacy beds.  Such steps may include checking 
with bed system manufacturers to identify compatible mattresses, rails, and accessories.  
Likewise, healthcare facilities may contact their equipment suppliers for entrapment 
mitigating solutions that may already be available.  Manufacturers should follow the 
appropriate FDA regulations regarding risk assessment, design controls, and documentation 
when developing mitigation components, attachments and other accessories to address 
entrapment risks in legacy hospital beds.  
 
Additional resources are available to help caregivers and health care providers assess the 
individual patients needs, consider and address entrapment risks, and recommend mitigation 
strategies.  See Appendix B for examples of additional resources.   
Exclusions 
The dimensional criteria described on pages 15-21 are recommended for a number of 
products, but not all types of hospital beds.  We are listing those products below for which 
some, or all, of the dimensional criteria are not recommended.  You can find more detailed 
descriptions of these products in 21 CFR Parts 880 and 890.  Please note that the products 
listed below are not free from risk of entrapment.  We continue to suggest that users identify 
and address areas of potential entrapment for each patient or resident through a 
comprehensive bed safety program. 
 
 Total exclusion from the scope of this guidance: 
  Air fluidized therapy beds are excluded because the nature of the therapy does not 
allow the patient to exit the bed easily.  When these products are used, we 
recommend that steps are taken to ensure that the therapeutic benefit outweighs the 
risk of entrapment. 
 
  Bariatric (obesity) beds, pediatric beds and infant cribs are excluded because we did 
not use anthropometric data for these groups in determining the recommended 
dimensional limits of the entrapment zones in this guidance.  
 
  Stretchers not used for extended-stay, examination tables, operating room tables, 
radiology tables, proning tables, exercise and range of motion tables, bathing units, 
and mechanical lifting devices are excluded from the scope of this guidance because 
they are not ordinarily used as hospital beds. 
 
Partial Exclusion from the scope of this guidance: 
  Kinetic treatment tables and rotation beds are excluded from the dimensional limits 
except for those spaces within the perimeter of the rail due to the special design 
requirements of these beds.  See Zone 1 description on page 15.  When these products 
are used, we recommend that steps are taken to ensure that the therapeutic benefit 
outweighs the risk of entrapment. 
   
8  Contains Nonbinding Recommendations 
 
 
  Labor, delivery, recovery, and postpartum (LDRP) specialty beds are excluded from 
the dimensional limits for the area under the rail at the end of the rail due to the 
special design requirements for obstetric care. See Zone 4 description on page 18. 
 
  Pressure Reduction Therapeutic Products 
Framed flotation therapy beds, powered air mattress replacements, and similar 
pressure reduction products that have therapeutic benefits such as reducing pressure 
on skin are easily compressed by the weight of a patient and may pose an additional 
risk of entrapment when used with conventional hospital bed systems.  When these 
types of mattresses compress, the space between the mattress and the bed rail may 
increase and pose an additional risk of entrapment.  While entrapments have occurred 
with the use of framed flotation therapy beds (specialty air beds built into a hospital 
bed frame) and air mattress replacements,12, 13  these products are excluded from the 
dimensional limit recommendations, except for those spaces within the perimeter of 
the rail.  See Zone 1 description on page 15.  This partial exemption is due to the 
highly compressible nature of these mattresses, which poses technical difficulties 
with measuring certain dimensional gaps in these types of products.  We will continue 
to work with the IEC to develop and refine test methods to address the risk of 
entrapment in bed systems using these products.   
 
Additional caution should be taken when using these products to ensure a tight fit of 
the mattress to the bed system.  If a powered air mattress is replacing a mattress on a 
bed system that meets the recommendations in the guidance with the original 
mattress, the resulting bed system with the new air mattress may still pose a risk of 
entrapment.  When these products are used, we recommend that steps are taken to 
ensure that the therapeutic benefit outweighs the risk of entrapment.   
 
NOTE:  FDA continues to recommend the dimensional limits in this guidance for bed 
systems using mattress overlays.  We recommend that steps be taken to assess the 
therapeutic benefit to the patient when applying a mattress overlay to a bed system 
that does not meet the recommended dimensional limits.  The clinical benefit should 
outweigh the risk of entrapment presented by use of such a system.  
 
Reporting an Entrapment Adverse Event 
 
FDA will continue to monitor adverse event data on entrapments in hospital beds.  Your 
complete and descriptive reports of each entrapment or near-entrapment adverse event will 
help FDA to monitor the safety of hospital beds.  When reporting an entrapment event, 
manufacturers and users often leave out details of the entrapment event that can be useful in 
                                                 
12 Miles SH.  Deaths between Bedrails and Air Pressure Mattresses, Journal of the American 
Geriatrics Society 2002; 50:1124-5. 
 
13 Joint Commission on Accreditation of Healthcare Organizations, Issue 17 Sentinel Event 
Alert: Bed Rail-Related Entrapment Deaths (Sept. 6, 2002). 
 
9  Contains Nonbinding Recommendations 
 
 
identifying the factors or conditions that led to the event.  Consequently, these reports only 
tell FDA that an adverse event took place. To improve the quality of entrapment adverse 
event reports, the following information is important and helpful to include: 
 
1.  the exact location or zone of entrapment (the zones described in this document and 
Appendix D can be used to help describe entrapment events) 
2.  the body part that was entrapped, and, if possible, the size of the entrapped body part 
(i.e., head breadth, neck diameter, chest depth) 
3.  the position of the rails (fully raised, intermediate, or lowered) 
4.  type of rails in use (full length, 34 length, 12 length, split rails or 14 length), and the 
number of side rails raised a the time of the event  
5.  the articulation of the bed deck (which sections of the deck were raised, and the 
approximate degree of elevation for each deck section) 
6.  mattress type, mattress height, and height of the rail from the top of the mattress, and 
7.  information on the size of the gap that contributed to the entrapment. 
 
More information on reporting adverse events to the FDA can be found at:  
http://www.fda.gov/cdrh/mdr/. 
 
Key Body Parts at Risk  
 
Three key body parts at risk for life-threatening entrapment in the seven zones of a hospital 
bed system discussed in this guidance are the head, neck, and chest.  International 
anthropometric data references have been used to determine the relative sizes of these body 
parts for the population at greatest risk for entrapment and to provide a guide for the 
dimensional limits that would reduce their risk of entrapment.  See Appendix D.   
Head 
To reduce the risk of head entrapment, openings in the bed system should not allow  
the widest part of a small head (head breadth measured across the face from ear to 
ear) to be trapped.  Country-specific anthropometric data show that a 1st percentile 
female head breadth may be as small as 95 mm (3 34 inches).  A dimension of 120 
mm (4 34 inches) encompasses the 5th percentile female head breadth in all data 
sources used to develop these recommendations, and includes 1st percentile female 
head breadth as reported in some data sources.   
 
FDA is therefore using a head breadth dimension of 120 mm (4 34 inches) as the basis 
for its dimensional limit recommendations.  This dimension is consistent with the 
dimensions recommended by the HBSW and the IEC. 
 
 
10  Contains Nonbinding Recommendations 
 
 
Rail 
Neck 
To reduce the risk of neck entrapment, 
openings in the bed system should not 
allow a small neck to become trapped.   
Mattress Deck 
 
Data show a 1st percentile female neck 
diameter of 79 mm (3 1/8 inches) [5th 
percentile = 83 mm (3 1/4 inches)].  
Several factors, such as neck 
Wedging  compressibility, loss of muscle mass in the 
neck when people age, and the 
asymmetrical shape of the neck, support the use of a reduced measurement.  For 
example, one published estimate for compressibility of neck tissue is 25% of the 
uncompressed measure.14  Reducing the 79 mm measure by approximately 25% to 
account for tissue compression gives a measure of 60 mm (2 3/8 inches).  Both the 
IEC and the HBSW recommend a dimensional limit of 60 mm (2 3/8 inches) to 
prevent neck entrapment.  Consistent with these recommendations, FDA is 
recommending 60 mm (2 3/8 inches) as an appropriate dimension for neck diameter. 
 
The concept of a wedging effect, which occurs when the neck is trapped in a V-
shaped opening, recurs throughout many national and international entrapment-
prevention standards (See Appendix C); however, the standards differ with respect to 
what is considered to be the critical angle for wedging.  Some standards specify 
minimum angles to prevent neck entrapment based on a theoretical analysis of the 
forces on a cylindrical object (representing the cross-section of a neck) in an angled 
space.  Depending on whether the wedging is considered to be caused by the total 
resultant forces on the neck or the horizontal components of the forces, the critical 
angles are identified as either 60 (See Appendix C, References 5 and 6) or 53 degrees 
(rounded up to 55) (See Appendix C, References 1,4 and 9), respectively.  
 
When developing its recommendations for preventing neck entrapment, HBSW 
consulted a published international standard for swimming pool equipment [see EN 
13451], which includes dimensional limits to prevent entrapment of various body 
parts of adults and children.  This standard specifies that V-shaped openings should 
be of angles greater than 60 degrees.  HBSW members performed analyses that 
support this limit, and the HBSW has recommended that V-shaped openings be 
greater than 60 degrees to avoid neck entrapment. 
   
Given the adult population at risk for wedging entrapments in hospital beds, FDA is 
recommending a dimension of 60 mm (2 3/8 inches) to represent neck diameter.  
                                                 
14 ASTM International.  Standard Consumer Safety Specification for Expansion Gates and 
Expandable Enclosures. Annual Book of ASTM Standards, Vol. 15.07, Appendix X2, 
Designation F 1004. 
 
11  Contains Nonbinding Recommendations 
 
 
Additionally, to prevent wedging, a limit of greater than 60 degrees is recommended 
for V-shaped openings that a neck could enter. These dimensions are consistent with 
the dimensions recommended by the HBSW and the IEC (see IEC 60601-2-38-1). 
 
Chest  
The openings in a bed system should be wide enough not to trap a large chest through 
the opening between split rails.  For purposes of the recommendations in this 
guidance, a 95th percentile male chest depth is used to represent the largest chest 
measure.  Although one would assume that the largest chest size belongs to women, 
breast tissue is compressible and diminishes in size as aging occurs.  Male chests, 
however, have less compressible tissue and do not diminish as significantly in size 
with aging.  A 95th percentile male chest depth of 318 mm (12 12 inches), measured 
from the nipple to the back, including the pectoral muscles, is used to represent the 
largest chest measure.   
 
The IEC is proposing to adopt a dimension to reduce chest entrapment of greater than 
318 mm (12 12 inches).   FDA concurs with the dimension of 318 mm (12 12 inches) 
to represent chest depth for the population vulnerable to entrapment, and has used this 
dimension as the basis for its recommended dimensional limits.  
 
 
The body part dimensions used to develop FDA's dimensional limit recommendations 
are summarized in Table 2 below. 
 
Table 2 
Key Body Part Dimensions 
Key Body Part  Dimension  
Head  120 mm (4 34 inches)  
Neck   60 mm (2 3/8 inches) and                 
an angle  >  60 degree  
Chest  318 mm (12 12 inches) 
12  Contains Nonbinding Recommendations 
 
 
Potential Zones of Entrapment 
 
This guidance describes seven zones in the hospital bed system where there is a potential for 
patient entrapment.  Entrapment may occur in flat or articulated bed positions, with the rails 
fully raised or in intermediate positions.  Descriptions of the seven entrapment zones appear 
on pages 15-21 in this guidance.  Summary drawings of entrapment for all of the zones 
appear in Appendix E. 
 
The seven areas in the bed system where there is a potential for entrapment are identified in 
the drawing below. 
 
Zone 1:  Within the Rail 
Zone 2: Under the Rail, Between the 
Rail Supports or Next to a 
Single Rail Support 
Zone 3: Between the Rail and the 
Mattress 
Zone 4: Under the Rail, at the Ends of 
the Rail 
Zone 5:  Between Split Bed Rails  
Zone 6:  Between the End of the Rail 
and the Side Edge of the 
Head or Foot Board 
Zone 7:  Between the Head or Foot 
Board and the Mattress End 
 
 
Entrapment at the Bed Deck or Frame 
 
Many of the entrapment event reports FDA received involved entrapment between the rail 
and the beds frame.  It is unclear from the event descriptions whether this refers to the 
mattress deck, the bed frame, or even the hardware attaching the bedrail to the bed system. 
While this guidance does not recommend dimensional limits on the space at the deck or 
frame locations, FDA believes that meeting the other recommended dimensional limits 
would reduce the possibility of entrapment at the deck or frame locations. 
 
 
 
 
 
 
 
 
 
13  Contains Nonbinding Recommendations 
 
 
A Retrospective Study of Entrapment Reports to FDA 
 
 FDAs adverse event reporting system helps promote product safety by collecting information 
on products that are currently on the market.  FDAs reporting system collects reports of adverse 
events15 that caused or may have caused a death, a serious injury, or a malfunction.  From 
January 1985 to March 2000, FDA received 390 entrapment event reports to its adverse events 
database from manufacturers, hospitals, nursing homes, and consumers.  In 2000, HBSW 
reviewed these adverse event reports and identified entrapment areas or zones in the bed system 
and the body parts at risk.  Based on its analysis of the reported adverse events, HBSW made 
recommendations for dimensional limits. 
 
A retrospective study conducted by members of HBSW compared the HBSW recommended 
dimensions with dimensions of the bed models identified in the adverse events reports. For each of 
the entrapment adverse events in the study where the model number of the bed was reported, a 
participating bed manufacturer provided information on the dimensions of the identified area where 
an entrapment was believed to have occurred16.  Four manufacturers provided this information. 
These data represented 215 (55%) of the 390 entrapment events.  This information provided a 
reference range typical of hospital beds currently available for use in acute, long term care, and 
home settings. 
 
The retrospective study compared the manufacturer-supplied information, in the aggregate, to 
the dimensions recommended by the HBSW.  If the size of the openings in the reported bed 
models did not meet the HBSW recommended limits, i.e., the openings in the reported beds 
were outside the limits of the recommended gap sizes, then the HBSW dimensional limits were 
considered to be an appropriate limit to reduce entrapments at that area.  We have considered 
the information from this study in developing the dimensional limit recommendations described 
in this guidance. 
                                                 
15 Note:  Many reports lacked a complete and detailed description of the adverse event.  The 
beds involved in these adverse events may not have had compatible mattresses or bed rails 
specifically designed for the particular bed model involved in the reported entrapments.  Also, 
information was limited regarding the condition of the beds, bed rails, and mattress at the time 
of the entrapments.  Specific details about the exact location of the entrapments within the beds 
were sometimes lacking.  Despite these limitations, adverse event reports can suggest a profile 
of the areas or locations on a hospital bed where entrapment can occur, as well as the parts of 
the body at risk for entrapment. 
 
16 When manufacturers measured the gaps for the retrospective study, they used mattresses of 
the size, type and thickness typically recommended for use with their bed models.  Mattresses 
involved in reporting entrapment events may have been different from the manufacturers 
recommended mattresses, which means actual gap sizes in entrapments involving the 
mattresses may have been different from those identified by the manufacturers in the 
retrospective study.  The manufacturers measurements may have been representative of best 
case measurements.   We also note that spaces in a hospital bed system may vary in size when 
the hospital bed system is articulated through the various ranges of motion.  For the 
retrospective study, manufacturers measured gap sizes with the beds in the flat position.  This 
means that if the bed was articulated in reported entrapments, the size of the gap may have 
been different from that provided by the manufacturers in the retrospective study.   
14  Contains Nonbinding Recommendations 
 
 
 
 
Dimensional Limits for Identified Entrapment Zones 1-4 
 
FDA is recommending dimensional limits for zones 1 through 4 at this time because we 
believe the majority of the entrapments reported to FDA have occurred in these zones.  We 
based these recommended limits upon the body parts entrapped in these individual zones 
identified through adverse event reports and entrapment scenarios described in the reports.  A 
summary table (Table 3) of the hospital bed dimensional limit recommendations appears on 
page 21 at the end of this section. 
 
The Hospital Bed Safety Workgroup developed and validated test methods to measure and 
assess gaps or openings in zones 1-4 of hospital bed systems, reprinted in Appendix F.  As a 
member of the HBSW, FDA participated in the development and validation of these test 
methods.  FDA recommends these test methods as an acceptable approach for assessing 
hospital bed gap sizes in accordance with the dimensional limitations described below.  The 
test methods and tool used to conduct these tests are available through HBSW (see Appendix 
B).  If an alternate approach is used to assess gap sizes, FDA recommends that the 
dimensional limits used in any alternative approach be at least as stringent as the ones 
described below.  
 
Zone 1  Within the Rail 
 
 
 
Zone 1 is any open space within the perimeter of the rail.  Openings in the rail should be 
small enough to prevent the head from entering. A loosened bar or rail can change the size of 
the space.  The HBSW and IEC recommend that the space be less than 120 mm (4 34 inches), 
representing head breadth.   
 
Data from the Retrospective Study 
 
Adverse events identified as occurring within the rail were reported in bed models where 
open spaces within the rail were greater than 120 mm (4 34 inches).  Manufacturers 
measurements of bed models representative of those identified in these incidents had spacing 
within the rail of between 177 mm (6.97 inches) and 190 mm (7.48 inches).  The data suggest 
that nearly all of these entrapment events may have been prevented if the spaces within the 
rails had been less than 120 mm (4 34 inches), representing head breadth as described above.    
Consistent with HBSWs and the IECs recommendations and comments received on the 
15  Contains Nonbinding Recommendations 
 
 
previously published draft FDA guidance, FDA is recommending a measure of less than 120 
mm (4 34 inches) as the dimensional limit for any open space within the perimeter of a rail.  
The space should not permit an object with a circular cross-section measuring less than 120 
mm (4 34 inches) in diameter to enter or pass through. 
 
Zone 2  Under the Rail, Between the Rail Supports or Next to a Single 
Rail Support  
 
   
 
 
This space is the gap under the rail between a mattress compressed by the weight of a 
patients head and the bottom edge of the rail at a location between the rail supports, or next 
to a single rail support.  If there is a single rail support, entrapment in Zone 2 can occur 
anywhere along the bottom length of the rail beyond the support, up to the end of the rail.  
(Entrapment at the end of the rail is explained in Zone 4.)  Factors to consider are the 
mattress compressibility17 which may change over time due to wear, the lateral shift of the 
mattress or rail, and any degree of play from loosened rails or rail supports.  A restless 
patient may enlarge the space by compressing the mattress beyond the specified dimensional 
limit.  This space may also change with different rail height positions and as the head or foot 
sections of the bed are raised and lowered. The space may increase, decrease, become less 
accessible, or disappear entirely.  In some positions, the potential for entrapment in this zone 
may still exist when the deck is articulated.   
 
Preventing the head from entering under the rail would most likely prevent neck entrapment 
in this space.  FDA recommends that this space be small enough to prevent head entrapment, 
less than 120 mm (4 34 inches).   IEC recommends the same dimensions but measures the 
space without the mattress in place.   
   
Data from the Retrospective Study 
 
In the study, the manufacturers were instructed to measure diagonally from the top edge of the 
compressed mattress to the lowest inside edge of the rail between the rail supports. This 
                                                 
17 "Mattress compressibility refers to the extent to which a mattress changes in dimension as 
a result of the weight of a patients body or body part moving on, across, or off of the 
mattress surface. The mattress dimension may also change as a result of articulation of the 
deck. 
 
16  Contains Nonbinding Recommendations 
 
 
measurement ranged from between 76 mm (3 inches) and 191 mm (7.5 inches). If the reported 
entrapments occurred at Zone 2, the data suggest that the HBSW recommended dimensional 
limit of less than 120 mm (4 34 inches) would have prevented only about half of the reported 
events at this zone.  At times, the adverse event report information was not clear, and it was 
difficult to determine the precise location of the entrapment and to determine whether it 
occurred in Zone 2, 3, or 4.  Most reports only stated that an entrapment occurred between the 
rail and the mattress.  However, given the scenarios in the reports, some of these events may 
have occurred at the rail end, beyond the support (Zone 4) as neck entrapments when the head 
entered under the rail first.17  
 
Because the data for reported entrapments at Zone 2 are not definitive and the most likely 
scenario for entrapment in this space would include a head-first entry, the dimensional limit 
of 120mm (4 34 inches) is being recommended. 
 
Zone 3  Between the Rail and the Mattress 
 
 
 
 
This area is the space between the inside surface of the rail and the mattress compressed by 
the weight of a patients head.  The space should be small enough to prevent head entrapment 
when taking into account the mattress compressibility, any lateral shift of the mattress or rail, 
and degree of play from loosened rails.  HBSW and IEC recommend a dimension of less than 
120 mm (4 34 inches) because the head is presumed to enter the space before the neck.  FDA 
is recommending a dimensional limit of less than 120 mm (4 34 inches) for the area between 
the inside surface of the rail and the compressed mattress.   
 
Data from the Retrospective study 
 
A review of the manufacturers supplied measurements indicates that the horizontal gap 
between the rail and the uncompressed mattress for bed models involved in entrapments 
believed to have occurred at Zone 3 was between 38 mm (1 12 inches) and 127 mm (5 
inches).  Theoretically, entrapment would involve compression of the mattress which would 
have resulted in a larger gap than the manufacturer measurements without patients present 
and, subsequently, a larger range of measures.  Further, it could not be determined from the 
description of entrapment events whether entrapments occurred at Zones 2, 3 or 4.   
FDA recommends a 120mm (4 34 inch) dimensional limit for this zone based on the head 
breadth dimension described above.   
17  Contains Nonbinding Recommendations 
 
 
Zone 4  Under the Rail at the Ends of the Rail 
 
   
 
This space is the gap that forms between the mattress compressed by the patient, and the 
lowermost portion of the rail, at the end of the rail.  Factors that may increase the gap size 
are: mattress compressibility, lateral shift of the mattress or rail, and degree of play from 
loosened rails.  The space poses a risk for entrapment of a patients neck.  It may change with 
different rail height positions and as the head or foot sections of the bed are raised and 
lowered. The space may increase, decrease, become less accessible, or disappear entirely.  
Thus, in some positions, the potential for entrapment in this zone may still exist when the 
deck is articulated.  
 
At the time of this publication, the IEC international standard recommends a dimensional 
limit of less than 60 mm (2 3/8 inches) measured between the mattress support platform and 
the lowest portion of the rail at the rail end to prevent neck entrapment.  Based on the neck 
diameter dimension described above, FDA recommends that the dimensional limit for this 
space also be less than 60 mm (2 3/8 inches).  To reduce the risk of neck entrapment at Zone 
4, FDA recommends consideration of the combination of the gap size and the angle size 
(created between the mattress and the rail).  Thus, FDA recommends that the V-shaped 
opening under the rail at its end be of an angle wide enough, i.e. greater than 60 degrees, to 
prevent wedging entrapment (See Neck Section on pages 11 and 12 for a description and 
diagram of wedging entrapments).   
 
Data from the Retrospective Study 
 
The retrospective study measures for Zone 4 ranged between 102 mm (4 inches) and 152 mm 
(6 inches) for the diagonal measure between the inside bottom edge of the rail at the end of 
the rail and the top of the compressed mattress.  It could not be determined from the 
entrapment event reports whether the entrapments occurred in Zone 4, or whether events 
reported as neck entrapment occurred as a result of head-first entry.  The HBSW 
recommended that a 60 mm dimension be used to represent neck diameter.  Later the HBSW 
identified the importance of avoiding wedging of the neck at the end of the rail, and 
concluded that a linear measure for the Zone 4 space would not adequately address mattress 
compressibility and wedging forces in Zone 4.  HBSW recommended that openings in Zone 
4 measure both less than 60 mm in size and greater than 60 degrees in angle.  FDA agrees 
with this recommendation. 
 
18  Contains Nonbinding Recommendations 
 
 
 
Zones 5, 6 and 7 
 
Although seven potential zones of entrapment have been identified by HBSW, FDA is 
recommending dimensional limits for zones 1-4 because these zones were most frequently 
reported as having entrapments.   The current international standard (IEC 60601-2-38) 
addresses limits for zones 1, 2, 4, and 6.  In addition, IEC intends to set or revise dimensional 
limits, for areas comparable to HBSWs zones 1-6 in their upcoming international standard 
for hospital beds.  FDA continues to receive entrapment reports for Zones 5 and 6, and Zone 
7 remains a potential for entrapment.  FDA will monitor entrapments in these zones and 
consider harmonization with the IEC standard once it is available.   
 
Zone 5  Between Split Bed Rails 
 
             
         
This zone occurs when partial length head and foot side rails (split rails) are used on the same 
side of the bed.  The space between the split rails may present a risk of either neck 
entrapment or chest entrapment between the rails if a patient attempts to, or accidentally, 
exits the bed at this location.  In addition, any V-shaped opening between the rails may 
present a risk of entrapment due to wedging.  FDA recognizes this area as a potential for 
entrapment and encourages facilities and manufacturers to report entrapment events at this 
zone. 
Zone 6  Between the End of the Rail and the Side Edge of the Head or 
Foot Board 
 
 
 
Zone 6 is the space between the end of the rail and the side edge of the headboard or 
footboard.  This space may present a risk of either neck entrapment or chest entrapment. In 
19  Contains Nonbinding Recommendations 
 
 
addition, any V-shaped opening between the end of the rail and the head or footboard may 
present a risk of entrapment due to wedging. This space may change when raising or 
lowering the head or foot sections of the bed.  This space may increase, decrease, become 
less accessible, or disappear entirely.  Thus, in some positions, the potential for entrapment 
may exist when the deck is articulated.  FDA recognizes this area as a potential for 
entrapment and encourages facilities and manufacturers to report entrapment events at this 
zone. 
 
Zone 7  Between the Head or Foot Board and the End of the Mattress   
 
 
 
Zone 7 is the space between the inside surface of the head board or foot board and the end of 
the mattress.  This space may present a risk of head entrapment when taking into account the 
mattress compressibility, any shift of the mattress, and degree of play from loosened head or 
foot boards.  FDA recognizes this area as a potential for entrapment and encourages facilities 
and manufacturers to report entrapment events at this zone. 
20  Contains Nonbinding Recommendations 
 
 
 
Table 3 Summary of FDA Hospital Bed Dimensional Limit 
Recommendations 
 
Zone   Dimensional Limit 
Recommendations  
   
1     
<120 mm (< 4 3/4 ) 
Within the rail          
2 
Under the rail, between rail supports       < 120 mm (< 4 3/4 ) 
or next to a single rail support 
3 
<120 mm (< 4 3/4 ) 
Between rail and mattress  
<60 mm (< 2 3/8 )  
4 
AND 
Under the rail, at the ends of the rail 
>60 angle 
21  Contains Nonbinding Recommendations 
 
 
 
APPENDIX A 
List of Hospital Bed Safety Workgroup (HBSW) Participating Organizations  
 
  AARP   
  American Association of Homes and Services for the Aging 
  American Health Care Association 
  American Medical Directors Association 
  American Nurses Association 
  American Society for Healthcare Risk Management/American Hospital Association 
  Basic American Metal Products 
  Beverly Enterprises, Inc. 
  Bilanx Consulting LLC 
  Care Providers of Minnesota 
  Carroll Healthcare, Inc. 
  ECRI 
  ElderTech Solutions, LLC 
  Exceptional Parent Foundation For Education 
  Evangelical Lutheran Good Samaritan Society 
  Hard Manufacturing Co., Inc. 
  HealthSafe Inc. 
  Hill Rom, Inc. 
  Huntleigh Healthcare 
  Iona Senior Services 
  Kinetic Concepts, Inc. 
  Law Offices of Julie A. Braun 
  Lockwood Consulting, LLC 
  Medical Devices Bureau, Health Canada 
  M.C. Healthcare Products 
  National Association for Home Care 
  National Citizens Coalition for Nursing Home Reform 
  National Patient Safety Foundation/American Medical Association 
  Posey Company 
  RN+ Systems / Tactilitics, Inc. 
  Span-America Medical Systems, Inc.  
  Stryker Medical 
  Sunrise Medical, Inc. 
  The ROHO Group, Inc. 
  Untie the Elderly, The Kendal Corporation 
  U.S. Department of Veterans Affairs 
  U.S. Food and Drug Administration 
  Vail Products Inc. 
 
Consulting Organizations to the Hospital Bed Safety Workgroup 
  Joint Commission on Accreditation of Healthcare Organizations 
  U.S. Centers for Medicare & Medicaid Services 
  U.S. Consumer Product Safety Commission 
22  Contains Nonbinding Recommendations 
 
 
APPENDIX B 
Additional Information and Kit Information 
 
Websites:         
Food and Drug Administration: 
  http://www.fda.gov/cdrh/beds 
 
Bureau of Medical Devices, Health Canada: 
  http://www.hc-sc.gc.ca/hpfb-dgpsa/tpd-dpt/index_advisories_professionals_e.html 
 
ECRI:   
  http://www.ecri.org/Patient_Information/Patient_Safety/BedSafetyClinicalGuidance.pdf 
 
HealthSafe, Inc.: 
  http://www.healthsafe.org/ 
 
Untie the Elderly, Kendal Corporation:   
  http://www.ute.kendal.org 
 
  American Association of Homes and Services for the Aging:   
  http://www.aahsa.org 
 
American Health Care Association:   
  http://www.ahca.org 
 
Kit Information: 
The HBSW Bed Safety Entrapment Kit will be available through National Safety 
Technologies at http://www.nst-usa.com.  The kit will include: 
   
  Documents 
  A Guide to Bed Safety (a brochure) from the Hospital Bed Safety Workgroup 
  Clinical Guidance and Decision Tree for the Assessment and Implementation 
of Bed Rails in Hospitals, Long Term Care Facilities and Home Care Settings 
from the Hospital Bed Safety Workgroup 
  Dimensional Test Methods for Bed Systems from the Hospital Bed Safety 
Workgroup 
  Instructional Video/DVD for bed measurement  
  A Guide for Modifying Bed Systems and the Use of Accessories to Reduce the 
Risk of Entrapment from the Hospital Bed Safety Workgroup 
Test tool kit 
 
Educational videotapes:  
  An educational videotape, Do No Harm  Hospital Bed Safety, explaining 
hospital bed and bed rail safety issues is produced by AARP.  
The AARP video is available through The Kendal Corporation. Ordering 
information can be obtained from http://www.ute.kendal.org/ 
23  Contains Nonbinding Recommendations 
 
 
APPENDIX C 
References for National and International Entrapment Standards 
 
1.  ASTM International.  Standard Consumer Safety Performance Specification for 
Playground Equipment for Public Use. Annual Book of ASTM Standards, Vol. 15.07, 
Designation F 1487. 
 
2.  ASTM International.  Standard Consumer Safety Specification for Expansion Gates and 
Expandable Enclosures. Annual Book of ASTM Standards, Vol. 15.07, Designation F 1004. 
 
3.  ASTM International.  Standard Consumer Safety Specification for Bunk Beds. Annual 
Book of ASTM Standards, Vol. 15.07, Designation F1427. 
 
4.  U.S. Department of the Army.  Child Development Center Play Area Inspection and 
Maintenance Program.  Publication No. TM 5-663. 
  Public domain document available at www.army.mil 
 
5.  European Committee for Standardization.  Playground Equipment  Part 1: General 
Safety Requirements and Test Methods.  Ref. No. EN 1176-1. 
Adopted and published under various national designations by 28 member countries 
of CEN, including France, Great Britain, Germany, and Sweden. 
 
6.  European Committee for Standardization.  Swimming Pool Equipment  Part 1: General  
Safety Requirements and Test Methods.  Ref. No. EN 13451-1. 
Adopted and published under various national designations by 25 member countries 
of CEN, including France, Great Britain, Germany, and Sweden. 
 
7.  16 CFR Part 1213, Safety Standard for Entrapment Hazards in Bunk Beds. 
 
8.  16 CFR Part 1513, Requirements for Bunk Beds.  
 
9.  U.S. Consumer Product Safety Commission.  Handbook for Public Playground Safety.  
Publication No. 325. 
Public domain document, available at www.cpsc.gov 
24  Contains Nonbinding Recommendations 
 
 
APPENDIX D 
Anthropometric References 
  
Anthropometric References used: 
 
Hall, Judith. Handbook of normal physical measurements. New York : Oxford University 
Press, 1990.   
[Note: Head width and neck circumference data for both sexes,-2SD (2.5th percentile), from 
birth to age 16.  Data visually extrapolated from graphs.] 
 
Jurgens, H., Pieper, U. International data on anthropometry. Geneva, Switzerland : 
International Labour Office, 1990. (Occupational safety and health series; no. 65).   
[Note: This report reviewed data for North America, Latin America (Indian population), 
Latin America (European and Negroid population, Northern Europe, Central Europe, Eastern 
Europe, South-Eastern Europe, France, Iberian Peninsula, North Africa, West Africa, South-
Eastern Africa, Near East, North India, South India, North Asia, South China, South-East 
Asia, Australia (European Population), Japan.] 
 
Peebles, Laura, Norris, Beverly J. Adultdata - The handbook of adult anthropometric and 
strength measurements: data for design safety. London : Department of Trade and Industry, 
1998.  
[Note: This handbook contains data from various sources for the following countries: UK, 
Brazil, France, Germany, Italy, Japan, Poland, Sri Lanka, Sweden, Netherlands, and USA. 
Data were not available from ALL these countries for EACH measurement.]  
 
Smith, Stuart, Norris, Beverly, Peebles, Laura. Older adult data  The handbook of 
measurements and capabilities of the older adult: data for design safety. London : 
Department of Trade and Industry, 2000.   
[Note: This handbook contains data from various sources for the following countries: UK, 
Brazil, France, Germany, Italy, Japan, Poland, Sri Lanka, Sweden, Netherlands, and USA. 
Data were not available from ALL these countries for EACH measurement.]  
 
Snyder, JRG. Anthropometry of infants, children and youths to age 18 for product safety 
design: final report. Bethesda, MD : Consumer Product Safety Commission, 1977. 
 
 
Others references consulted: 
 
Association for the Advancement of Medical Instrumentation. Human factors engineering 
guidelines and preferred practices for the design of medical devices. 2nd ed. Arlington, VA : 
Association for the Advancement of Medical Instrumentation, 1993 ; AAMI HE-48 1993. 
 
British Standards Institution. 1987 Ergonomics  standards and guidelines for designers. 
United Kingdom : British Standards Institution, 1987 ; document no. PP 7317. 
 
25  Contains Nonbinding Recommendations 
 
 
Damon, Albert, Stoudt, Howard W., McFarland, Ross A. The human body in equipment 
design. Cambridge, MA : Harvard University Press, 1966. 
 
Diffrient, Niels. Humanscale one-two-three. Cambridge, MA : MIT Press, 1974. 
 
Human engineering design data digest. Washington, DC : U.S. Government Printing  
Office, 1975.  
 
National Center for Health Statistics. Weight, height, and selected body dimensions of adults, 
United States, 1960-62. Hyattsville, MD: National Center for Health Statistics, 1980; DHHS 
publication no. (PHS) 80-1301. Vital and health statistics; series 11, no. 8. 
 
Salvendy, Gavriel, ed. Handbook of human factors. New York : John Wiley & Sons, 1987. 
 
Woodson, Wesley E. Human factors design handbook : information and guidelines for the 
design of systems, facilities, equipment and products for human use. New York : McGraw-
Hill Book Company, 1981. 
 
Woodson, Wesley E., Conover, Donald W. Human engineering guide for equipment 
designers. 2nd ed. Berkeley, CA : University of California Press, 1970. 
 
Woodson, Wesley E., Tillman, Peggy, Tillman, Barry. Human factors design handbook. 2nd 
ed. New York : McGraw-Hill Professional, 1992. 
 
26  Contains Nonbinding Recommendations 
 
 
 
APPENDIX E 
Drawings of Potential Entrapment in Hospital Beds 
 
Zone 1  Entrapment within the rail     Zone 2  Entrapment under the rail, 
between the rail supports or next to a single 
 
rail support 
 
 
     
Zone 3  Entrapment between the rail       Zone 4 Entrapment under the rail,         
 
and the mattress  at end of rail  
   
     
Zone 5  Entrapment between split    Zone 6 Entrapment between the           
end of the rail and the side edge             
 bed rails 
of the head or foot board 
 
 
     
 
Zone 7  Entrapment between head or   
foot board and the mattress end 
 
27  Contains Nonbinding Recommendations 
 
 
APPENDIX F 
Hospital Bed Safety Workgroup  
Dimensional Test Methods for Bed Systems 
28  Contains Nonbinding Recommendations 
 
 
 
Dimensional Test Methods for Bed Systems 
 
 
July 2005 
 
Introduction 
The Hospital Bed Safety Workgroup (HBSW) and the U.S. Food and Drug Administration (FDA) 
have defined seven numbered "zones" or spaces in and around hospital bed systems where patients 
could potentially become trapped.  Actual entrapments have been reported in six of these zones, with 
Zones 1, 2, 3, and 4 accounting for approximately 80% of entrapment events reported to the FDA.  
This appendix contains instructions for testing Zones 1, 2, 3, and 4, using tools and methods 
developed by the HBSW.   
 
Contents 
Summary of Test Zones.......................................................................................................................................2 
Description of Test Tools.....................................................................................................................................3 
Cone and Cylinder Tool.....................................................................................................................................3 
Tool Assembly and Disassembly.......................................................................................................................3 
Using the spring scale........................................................................................................................................4 
General Testing Considerations..........................................................................................................................4 
Test Methods 
Zone 1 Test........................................................................................................................................................5 
Zone 2 Test........................................................................................................................................................6 
Zone 3 Test........................................................................................................................................................8 
Zone 4 Test......................................................................................................................................................10 
Appendix: Testing Tips and Frequent Questions............................................................................................12 
SAMPLE DATASHEETS..................................................................................................................................17 
1  Contains Nonbinding Recommendations 
 
 
Summary of Test Zones 
The four (4) tests in these instructions measure gaps within bed systems where a patient could 
become trapped. Each test measures a different area, or zone, where entrapment can occur:  
Zone 1: Within the rail  
 
Zone 1 
Figure 1.  The Zone 1 test assesses the potential for head entrapment within the rail (shaded areas). 
Zone 2: Under the rail between the rail supports or next to a single support 
Zone 2 
Figure 2.  The Zone 2 test assesses the potential for head entrapment under the rail, between the rail supports (or 
next to a single rail support) (shaded areas). 
Zone 3: Between the rail and the mattress 
  Side rail
Zone 3
Zone 3
Side rail 
Mattress  Mattress
 
Figure 3. The Zone 3 test assesses the potential for head entrapment between the edge of the mattress and the inside 
of the rail (shaded areas). 
Zone 4: Under the rail at the end of the rail 
Zone 4 
Figure 4.  The Zone 4 test assesses the potential for neck entrapment between the top of the mattress compressed 
by the patient and the lower-most portion of the rail at the end of the rail (shaded areas). 
2  Contains Nonbinding Recommendations 
 
 
Description of Test Tools 
Each test requires the use of simple tools, including a cone, a cylinder, and a spring scale.  Your tools 
may look slightly different from the tools in the figures, but they will work the same way.                 
Cone and Cylinder Tool 
The cone and cylinder is a combination tool (see Figure 5). It can be easily taken apart so that the 
cone and cylinder can be used separately.  Tests 1, 2 and 3 use only the cone.  Test 4 uses the 
combined assembled tool.  
(cid:131)  The diameter of the large end of the cone represents 
the  width  of  a  small  adult  head  (120  mm,  or 
approximately 4 34 inches). 
(cid:131)  The diameter of the cylinder represents the size of a 
small  adult  neck  (60  mm,  or  approximately  2  3/  
8
inches). 
(cid:131)  The cone and cylinder together weigh 15 lbs.  This 
represents the combined weight of an adult head (12 
lbs.) and neck (3 lbs.). 
(cid:131)  The red area of the cylinder defines contact angles in 
which the neck could become wedged (60 degrees or 
narrower), 
 
The cone tool includes the following features: 
Figure 5.  Cone and cylinder tool. 
(cid:131)  A loop at the end for attaching a spring scale. 
(cid:131)  A safety strap. 
(cid:131)  A marked center line on the large face of the cone.   
The cylinder includes the following features: 
(cid:131)  Red and green zones for identifying pass/fail at siderail ends. 
(cid:131)  A level to aid in tool positioning. 
To prevent personal injury during the measurement process, attach the strap to a secure point on the 
bed and shorten the length of the safety strap enough to keep the tool from dropping on your feet if it 
should  fall  during  a  test.  Make  sure  the  strap  is  long  enough  to  not  interfere  with  the  test 
measurement. 
Tool Assembly and Disassembly 
Note: General procedures for tools with a screw-type connection are described here.  (Your tool may 
have a different type of connection.)  Follow the instructions supplied with your tools for more 
detailed information. 
To take the cone and cylinder tool apart: 
1. Turn the knob to loosen and remove the connection shaft. 
2. Pull the cylinder from the cone. 
To put the cone and cylinder tool together: 
1. Align the red and green areas of the cone and cylinder. 
2. Insert the pins of the cone into the cylinder. 
3. Insert the connection shaft and turn the knob to tighten. 
3  Contains Nonbinding Recommendations 
 
 
Figure 6.  Disassembly and assembly of the cone and cylinder tool. 
 
Using the spring scale 
Use the spring scale to apply 12 lbs of force to the cone 
when testing Zones 1 and 2. At the small end of the cone 
tool, insert the scale hook into the metal loop. Pull the 
scale slowly until the needle points to 12 lbs. 
For other types of scales (sliders, digital, etc.), and for 
information on scale calibration, consult the instructions 
supplied with your toolkit.   
Figure 7.  Use of spring scale. 
 
General Testing Considerations 
  Bed Occupancy: For ease of mattress movement and measurement, and general safety, the patient 
should not be in the bed during the measurement procedures. 
  Bed Height: To avoid unnecessary bending or back strain, position the bed at a comfortable 
working height. 
  Bed Wheels: To prevent movement of the bed during testing, lock the wheels. 
  Linens/Sheets: Perform the tests with sheets in place as is typical for patient care.  Remove any 
pillows and blankets.  
  Infection Control: To avoid cross-contamination, disinfect the tools each time a different bed is 
measured. Follow the suppliers recommendations for tool disinfection. 
  Personal Safety: To avoid injury, use care when pulling the tool through openings in the bed rails.  
If the tool suddenly pulls through, you could lose your balance and fall.  Always use 
the safety strap to keep the tool from injuring your feet if it falls. 
  Intermediate Rail Position: Some rails have an intermediate stopping position or a high and low 
locking position.  Follow the individual test instructions, which may require testing 
the rails at both positions. 
  Bed Position: Most tests should be done with the bed in the flat position.  The exception is the test 
for Zone 2.  Follow the individual test instructions carefully. 
  Testing Tips: Consult the Appendix for helpful information.  
 
 
4  Contains Nonbinding Recommendations 
 
 
Zone 1 Test 
This test assesses the potential for head entrapment within the perimeter of the rail. 
The tools needed to do this test are the cone, the safety strap and the spring scale. 
Prepare for the Zone 1 Test: 
1.  Lock the wheels. 
2.  Put the bed in the flat, horizontal position.   
3.  Fully raise all bed rails.   
4.  Position the bed at a comfortable working height.  
Do the Zone 1 Test: 
1.  With the cone resting on mattress, attach the safety strap of the cone 
to the rail being tested.  Make sure the strap is short enough to keep 
the tool from injuring your feet if it falls, and long enough so it does 
not interfere with the test. 
2.  From inside the rail, insert the cone, small end first, into the largest 
opening in the rail.  Try to pull the tool through the space (figure 8).   
3.  If the tool does not pull through freely, attach the spring scale to the 
loop on the small end of the cone.  Try to pull the cone through the 
rail by pulling on the attached spring scale using 12 lbs. of force.  
Use  care  when  pulling.  If  the  tool  suddenly  pulls  through  the 
opening, you may lose your balance and fall, or the tool may fall on   
you.    Figure 8. Zone 1 test 
(within the rail). 
4.  Repeat steps 2 and 3 to check all other openings within the same rail. 
5.  Interpret test result.  
Interpret the Zone 1 Results: 
If the large end of the cone does not enter any of the openings, this space passes the test (figure 9a). 
If the large end of the cone does enter or pass through any of the openings, this space fails the test 
(figure 9b). 
 
   
Figure 9a.  Zone 1 test: Pass, large end of cone  Figure 9b.  Zone 1 test: Fail, large end of cone 
does not enter rail opening.  does enter rail opening. 
   
 
 
Repeat the Zone 1 Test: 
On the other rails: Repeat the test for all other rails on the bed. 
5  Contains Nonbinding Recommendations 
 
 
Zone 2 Test 
This test assesses the potential for head entrapment under the rail, at a location between 
the rail supports or next to a single support. 
The tools needed to do this test are the cone, the safety strap and the spring scale. 
 
Prepare for the Zone 2 Test: 
1.  Lock the wheels. 
2.  Fully raise all bed rails.   
3.  Position the bed at a comfortable working height.  
Do the Zone 2 Test:   
1.  Firmly push the mattress away from the rail 
being measured until it stops. 
2.  Identify the space where the test will be done 
(see Figure(s) 10a and 10b). 
3.  Determine whether the bed will be tested in the 
flat position or a different position: 
  Raise and lower the head and foot sections of 
the bed while you observe the space that will   
be tested.   Figure 10a.  Zone 2 test between rail supports. 
 
  If the space(s) where the test will be done 
 
becomes smaller or does not change as the 
bed moves, do the test with the bed in the flat 
position.  (See the Appendix for examples.) 
  If the space(s) becomes larger as the bed 
moves, find the bed position that creates the 
largest space.  Perform the test with the bed in 
the position where the space is the largest.    
(See the Appendix for an example.)   Figure 10b.  Zone 2 test for a single rail 
support. 
4.  Attach the safety strap of the cone to the rail 
being  tested.    Make  sure  the  strap  is  short 
enough to keep the tool from injuring your feet 
if  it  falls,  and  long  enough  so  it  does  not 
interfere with the test.   
5.  From the inside of the rail, insert the cone, small end first, into the gap between the mattress 
and the lower edge of the rail, between the rail supports.  Let the cone compress the mattress. 
Do not force the cone into the area. 
6.  Attach the spring scale to the loop on the cone.   
7.  Pull on the spring scale with 12 lbs of force at any angle that increases the chances of the cone 
going through the space. Use care when pulling. If the tool suddenly pulls through the opening, 
you may lose your balance and fall, or the tool may fall on you.  Observe whether the large end 
of the cone enters through the opening. 
8.  Interpret test result. 
6  Contains Nonbinding Recommendations 
 
 
Interpret Zone 2 Test Results: 
If the large end of the cone does not enter the space under the rail, or pass under the rail, this space 
passes the test (figures 11a and 11b). 
If the large end of the cone does enter the space under the rail, or if it passes under the rail, this space 
fails the test (figures 11c and 11d).  
Figure 11a.  Zone 2 test: Pass.  Figure 11b.  Zone 2 test: Pass. 
Figure 11c.  Zone 2 test: Fail.  Figure 11d.  Zone 2 test: Fail. 
Repeat the Zone 2 Test:  
On the same rail: If the rail has intermediate locking positions, perform the test for every intermediate 
position.   
On the other rails: Perform the test for all other rails on the bed, including intermediate and raised 
positions. 
7  Contains Nonbinding Recommendations 
 
 
Zone 3 Test 
This test assesses the potential for head entrapment between the inside of the rail and the 
surface of the mattress (compressed by the weight of a patients head).  
The tools needed for this test are the cone and the safety strap. 
Prepare for the Zone 3 Test: 
1.  Lock the wheels. 
2.  Put the bed in the flat, horizontal position.   
3.  Fully raise all bed rails.   
4.  Position the bed at a comfortable working height.  
Do the Zone 3 Test: 
1.  Firmly push the mattress away from the rail being measured until it stops. 
2.  Put the cone near the rail being tested and attach the safety strap.  Make sure the strap is short 
enough to prevent the tool from injuring your feet if it falls, and long enough so it does not 
interfere with the test.   
3.  Gently place the cone horizontally in the gap (figure 12a). Do not push the tool down into the 
gap. 
4.  Turn the cone until the line on the face of the large end is horizontal (figure 12b).   
5.  Let the cone sink into the space by its own weight.  If the cone is tilted, use one hand to gently 
level it (figure 12c).  Do not push the tool down into the gap. 
  Note:  If a mattress stop, rail support, or other structure keeps the cone from sinking in the gap, 
put the cone tool at a different location along the rail where there is no interference.   
6.  Determine whether the cones center line is above or below the surface of the mattress.  
7.  Interpret test result.  
Figure 12a. Zone 3 test: between the mattress and the inside of the rail. 
 
 
Figure 12b.  Zone 3 test: turning the cone. Figure 12c.  Zone 3 test: tilting the cone.
8  Contains Nonbinding Recommendations 
 
 
Interpret Zone 3 Test Results: 
If the line across the flat end of the cone is above the surface of the mattress, the space passes the test 
(figure 13a). 
If the line across the flat end of the cone is at or below the top surface of the mattress, the space fails 
the test (figure 13b). 
   
Figure 13a.  Zone 3 test: Pass  Figure 13b.  Zone 3 test: Fail 
(line above mattress surface).  (line below mattress surface). 
Repeat the Zone 3 Test: 
On the same rail: If the rail has any intermediate positions, perform the test at every intermediate 
position. 
On the other rails: Perform the test for all other rails on the bed, including the intermediate positions. 
 
9  Contains Nonbinding Recommendations 
 
 
Zone 4 Test 
This  test  assesses  the  potential  for  neck  entrapment  between  the  top  of  the  mattress 
(compressed by the patient) and the lower-most portion of the rail, at the end of the rail. 
The tools needed for this test are the assembled cone and cylinder with safety strap. 
Prepare for the Zone 4 Test:  
1.  Lock the wheels.  
2.  Put the bed in the flat, horizontal position.   
3.  Fully raise all bed rails.   
4.  Position the bed at a comfortable working height.  
Do the Zone 4 Test: 
1.  Firmly push the mattress away from the rail being tested until it stops. 
2.  Attach the safety strap of the cone tool to the rail being tested. Make sure the strap is short 
enough to prevent the tool from injuring your feet if it falls, and long enough so it does not 
interfere with the test.    
3.  Just beyond the end of the rail, rest the cone 
portion  of  the  cone  and  cylinder  tool  on  the 
mattress. The test area is shown in Figure 14.  (If 
the bed has split rails, you may need to lower the 
rail next to the one being measured to make room 
for the tools.) 
Note:  If the cylinder tool cannot fit into an area 
between the head or footboard and the end of a 
rail, the space passes.   Figure 14.  Zone 4 test area: under the rail 
at the end of the rail. 
4.  Position the tool so that the large face of the cone 
is flush or even with the edge of the mattress 
(figure 15a).  
5.  Let the weight of the cone compress the mattress, but do not force the tool down onto the mattress 
or under the rail.  Slide the tool towards the rail until it touches the rail or support (figure 15b). 
Figure 15a.  Align cone with edge and rest on mattress.  Figure 15b.  Slide the tool towards the 
rail until it makes contact. 
6.  Hold the cylinder section and use the level on the end of the cylinder to keep the cone level.   
10  Contains Nonbinding Recommendations 
 
 
7.  If the cylinder slides completely under the rail, this space fails.  If the cylinder touches the rail, 
observe the color on the cylinder where it makes contact: Red fails; Green passes (figure 16). 
8.  Interpret test result. 
 
Interpret Zone 4 Test Results: 
If the cylinder touches the rail in the green area, the space passes (figure 16a). 
If the cylinder touches the rail in the red area, the space fails (figure 16b). 
If the cylinder passes completely under the rail, the space fails (figure 16c). 
Reminder: If the cylinder tool cannot fit into an area between the head or footboard and the end of a 
rail, the space passes.  
contact  contact 
point  point 
Figure 16a.  Zone 4 test Pass  Figure 16b.  Zone 4 test Fail  Figure 16c.  Zone 4 test Fail 
(contact in green).  (contact in red).  (tool passes completely under rail). 
 
Repeat the Zone 4 Test: 
On the same rail: If the rail has any intermediate positions, perform the test at every intermediate 
position. 
On the other rails: Perform the Zone 4 test at both ends of all other rails on the bed, including the 
intermediate positions. 
11  Contains Nonbinding Recommendations 
 
 
Appendix to HBSW Dimensional Test Methods for Bed Systems  
Testing Tips and Frequent Questions 
 
Do I have to do the tests in order? 
No.  You may do the tests in any order you wish.  You may find it convenient to do all the tests on 
one side of the bed, then the other (to keep from repeatedly pushing the mattress back and forth).  
Or, you may wish to do all of the tests that use just the cone, then all of the tests that use the cone 
and cylinder together (to avoid having to put the tool together and take it apart several times). 
 
Do I have to use the safety strap?  
The test tools are heavy, and the safety strap helps protect you if they fall or suddenly pull through 
a gap.  Not using the safety strap increases your risk of being injured. 
 
How do I keep track of my test results? 
You may use any method that meets the recordkeeping requirements of your institution.  HBSW 
has developed some sample data sheets that you may use or modify according to your needs.  
Sample data sheets are attached at the end of this document.  
 
What are the most common mistakes people make when doing the tests? 
In field tests conducted to evaluate the test tools and instructions, some of the most common errors 
made by the testers were: 
  Not pushing the mattress away from the test location 
  Pulling the mattress toward the test location (instead of pushing it away) 
  Not articulating the bed enough to create the largest possible gap in Zone 2 
  Not having the bed flat when testing Zones 1, 3, or 4 
  Not aligning or leveling the tool properly 
  Forcibly pushing the tool into gaps 
 
When pushing the mattress, how hard do I need to push? 
Some test instructions ask you to push the mattress "until it stops." Usually that means pushing 
until either: 
  the mattress retention system (such as mattress stops, straps, or Velcro) engages and 
keeps you from pushing the mattress any further, or 
  the mattress stops against the opposite side rail(s). 
Always make sure you push the mattress straight across; it should not be crooked on the bed. 
 
When testing Zone 2, what position should the bed be in? 
Unlike the other three tests, the Zone 2 test is not always done with the bed in the flat position.  
Before you do the Zone 2 test, you first need to find the correct testing position.  With the bed in 
the flat position, identify the location of the Zone 2 space.  Then, articulate the bed (adjust the head 
and knee sections) while you watch the Zone 2 space. As you articulate the bed, the Zone 2 space 
may get bigger, get smaller, or stay the same.  Adjust the position of the bed until you find the 
position that makes the largest opening in Zone 2.  If the size of the opening gets smaller, or does 
not change, return the bed to the flat position to do the test.  Some examples of how Zone 2 might 
change with articulation are shown below. 
12  Contains Nonbinding Recommendations 
 
 
 
 
 
In this example, the opening in  In this example, the size of the  In this example, the Zone 2 
  Zone 2 gets larger when the  Zone 2 opening does not  openings get smaller when 
  bed is articulated (because of  change as the bed articulates  the bed is articulated.  Zone 2 
the bend in the mattress).   (the rail and the mattress stay  should be tested with this bed 
 
Zone 2 should be tested with  in the same relative position).   in the flat position. 
  this bed in the position where  Zone 2 should be tested with  (Note: For the rail design shown 
  the space is largest.  this bed in the flat position. below, Zone 2 and Zone 1 are the 
same.  See the discussion of 
  unusual rail designs.)
 
 
Zone 2
  Zone 2 Zone 2  Zone 2 
Mattress
  Mattress  Mattress 
 
Flat position  Flat position
  Flat position
  Zone 2
 
 
  Zone 2 
Zone 2
 
 
  Articulated position  Articulated position Articulated position
 
 
What if one of the Zones doesn't seem to exist on a particular bed system? 
If a zone doesn't exist on a particular bed, then there is no risk of a patient becoming trapped 
in that Zone.  For example: if there are no openings in a rail, then a patient could not get his 
or her head trapped in Zone 1 of that rail.  Your facility's policy and method of recordkeeping 
will determine how you should record data for Zones that do not exist.  For example, your 
facility may use customized data sheets that simply omit zones or rails that do not exist.  If 
you are using a generic form (such as a table or spreadsheet), it may be appropriate to record 
a result of either pass, not applicable, or not tested,  or to cross out entry spaces for 
Zones that do not exist.  (You should provide some indication that the Zone was not 
accidentally omitted from testing.) 
  
I need to test a bed with an unusual rail design.  The rails don't look like any of the rails 
shown in the instructions or video.  How do I figure out where to do each test? 
Occasionally, the most difficult part of a test may be figuring out where on the bed to 
perform the test.  For some beds or rail configurations, it may be difficult to identify the 
locations of various Zones.  The following hints and examples for each Zone may help. 
 
Zone 1: The goal of the Zone 1 test is to see whether a patient could become trapped by 
putting his or her head through an opening in the rail itself. 
 
Example: No openings in the rail 
If there are no openings in the rail, then there is no risk of entrapment in Zone 1.  
Examples of cases where there may not be any openings in the rail are: 
13  Contains Nonbinding Recommendations 
 
 
 The rail consists of a solid panel 
 The rail has a cover on it, and the cover blocks all the openings in the rail (whether 
you can see through the cover or not). 
 
 
Zone 2: The goal of the Zone 2 test is to see whether a patient could become trapped by 
putting his or her head under the rail, head first, between the rail supports (or next to a 
single support). (Note: Trapping the head by sliding the neck under the rail sideways is 
addressed by the test for Zone 4.) 
 
Example: Rail supports form part of the rail 
In some designs, the rail supports also form 
part of the body of the rail.  Crib-style rails, 
shown here, are common examples.  Often, 
when the rail supports form part of the rail, 
Zones 1 and 2 overlap.  Zone 1 should be 
tested with the bed in the flat position; if the 
Zones 1 and 2 
size of the space changes with articulation, 
the result for Zone 2 may be different.  
 
 
Zone 3: The goal of the Zone 3 test is to see whether a patient could become trapped with 
his or her head in the horizontal space between the rail and the mattress.  Usually, the 
gap in Zone 3 is easily identified, even if the rail design is unusual. 
 
 
Zone 4: The goal of the Zone 4 test is to see whether a patient could become trapped by 
sliding or wedging his or her neck under the end of the rail. 
 
Example: The rail end is very close to head/foot board (very little space in between) 
When testing in Zone 4, do not try to force the cylinder down between the rail and the 
end board or insert it under the rail from behind.  If the cylinders diameter will not fit 
between the end of the rail and the head or foot board, record a result of Pass for Zone 
4. 
Example: Full-length rail with horizontal supports at the ends End Board
An example of this rail type is shown at the right.  The 
cylinder cannot pass between the end of the rail and the 
head/foot board and then under the rail -- it would stop on the 
support.  The result for Zone 4 is Pass, because a patient 
would not be able to get his or her neck under the rail without 
the head or body going under first.  The potential for head- Mattress
first entrapment under the rail should be evaluated using the 
test for Zone 2.   
Rail Support Rail
14  Contains Nonbinding Recommendations 
 
 
 
Example: The end of the rail is vertical 
When the end of the rail is completely  Test as usual for Zone 
vertical from top to bottom, there may be  4 at this end of the rail. 
no space "under" the end of the rail 
where the cylinder (or a patient's neck) 
could fit.  In the example at right, the left 
side of the rail is vertical, and there is no 
space under the end of the rail.  For the 
left rail end in the figure, the rating for 
Zone 4 should be either pass or not 
applicable, depending on your facilitys 
policy.  The right end should be tested as 
usual for Zone 4. 
Note: If you are unsure about a particular 
rail you are testing, you should go ahead  There is no space "under" the 
and perform the Zone 4 test to verify your  rail at this end; you can verify 
answer.  The cone and cylinder would  by doing the Zone 4 test in the 
give a result of Pass if they were used to  shaded area if you are unsure. 
physically test the area shown on the left 
side of the rail in the figure.   
 
Why did my co-worker and I get different results for the same test? 
Different testers can get different test results for the same bed system.  Or, the same tester 
may get a different result when he or she repeats a test.  Some reasons this can happen are: 
  Different people may handle the tools slightly differently. 
  An error or oversight can affect the test result (see common errors below). 
  When a test is a very close call, some testers may be biased toward passing, and 
others toward failing. 
  A long time has elapsed between tests (mattresses vary in softness, and can compress 
over time; rails or rail supports may loosen or bend over time). 
 
What if a result is too close to call? 
If you are faced with a borderline pass/fail decision, use your best judgment to decide on a 
result.  You can also try these suggestions: 
  Repeat the test, and double-check that you did every step correctly. 
  If possible, get a second opinion.  Ask a co-worker for help. 
Your facility may also have suggestions or procedures for handling close calls.  For beds 
with borderline passes that result from close calls, you may wish to consider mitigation (see 
the next question below). 
 
15  Contains Nonbinding Recommendations 
 
 
What should I do if a bed system fails one of the tests? 
You should strongly consider mitigation of entrapment risks for bed systems that fail any of 
the four tests.  You may also wish to consider mitigation for bed systems that have borderline 
passes.  Mitigation may include patient assessment; some patients are at lower risk for 
entrapment than others.  For more information, consult the following, available at 
http://www.fda.gov/cdrh/beds: 
  Clinical Guidance for Assessment and Implementation of Bed Rails in Hospitals, 
Long Term Care Facilities and Home Care Settings 
  A Guide for Modifying Bed Systems and Using Accessories to Reduce the Risk of 
Entrapment  
 
 
What if I have a question that wasn't answered here? 
There are several resources available to help address questions.  As a start, you may contact 
the supplier of your beds, mattresses, or rails.  Your tool kit supplier is another resource.  In 
addition, an advisory group is being established by the HBSW to address additional questions 
that arise.  You may submit questions to that committee via the Web at [URL to be 
determined, www.xxx.yyy].  
 
 
  
 
16  Contains Nonbinding Recommendations 
 
 
If the bed has 4 rails, use these boxes for the headrails. If the bed only has 2 rails, use these boxes to record your results.   ZONE  3: P F    P      F  P      FZONE  2: P F ZONE  4 :   ZONE  4 :  ZONE  1: P F  SAMPHLEREAFR( DraDepum ai ilBAlosloivlwOleeTysd Ad)A  R SDHEET ZONE  1: P F ZONE  4 : ZONE  4 :    ZONE  2: P F P      F P      F   ZONE  3: P F  If the bed only has 2 rails, use these boxes to record your results.   If the bed has 4 rails, use these boxes for the headrails.
 
 
Leave them blank or cross them ouIf the bed has 4 rails, use these box ZONE 3: P      F   ZONE  2: ZONE  4 :   ZONE  1:  P F  P F ZONE  4 :  P      F P F  ecord your results for the m out if the bed does not have foot 
t if the bed does not have foot rails. es to record your results for the footr PF PF P F ZONE  4 :  P F  FOOT  BOARD ZONE  1:   ZONE  2: ZONE  4:    P      F ZONE  3:  e bed has 4 rails, use these boxes to r.  Leave them blank or cross therails
a ht
ils f too
.   If
17  Contains Nonbinding Recommendations 
 
 
 
If the bed has 4 railsIf the bed only has 2 P      F  ZONE  4 :  SAMPHLEEA DD  BAOTAARSDHEET ZONE  4 :  P      F  record your results.   headrails.
, use these boxes for the h rails, use these boxes to r PF ZONE  3:    P F  ZONE  2:  R(repmaillooivwlesd )  ZONE  2:  P F    ZONE  3:  P F  2 rails, use these boxes to s, use these boxes for the 
eadrails. ecord your results.   P      F ZONE  4 : IntPeorsmiteidonia te ZONE  4 :  P      F  If the bed only has If the bed has 4 rail
 
 
Leave them blank or cross them out if the bed doeIf the bed has 4 rails, use these boxes to record yo PF ZONE  3: P      F   ZONE  4 : P F  ZONE  2:  ZONE  2:  P F  ZONE  4 :   ZONE  3: P      F  PF hese boxes to record your results for the nk or cross them out if the bed does not have foot 
s not have foot rails. ur results for the footr PF ZONE  4 :  FOOT  BOARD ZONE  4:  P      F  e bed has 4 rails, use t.  Leave them blarails
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.   If
18