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Mar 04 2010

Anti-Ligature Knob

Category: Locks & KeysLori @ 12:57 am Comments (14)

Anti Ligature Knob and ThumbturnI got a call this week from a facility that needed to replace existing locksets with an anti-ligature product.  If you’re not familiar with anti-ligature hardware, it’s designed for use in mental health or detention facilities, to help protect patients or inmates from self-harm by minimizing the attachment points on the hardware.  Anti-ligature hardware is just one part of a safe environment for facilities with special needs, along with tamper-proof plumbing, mechanical, and electrical devices, break-away shower rods and bars, impact-resistant glass and mirrors, etc.

In the facility I met with today, the existing locks are Schlage L9000 series which made the process very easy.  Schlage has recently introduced the SK1 anti-ligature knob, which can be added to existing L9000 locksets with no change to the door preparation.

Here’s some additional information about the SK1:

  • Quad-grip knob design is easy to operate.
  • Positive stops limit rotation of thumbturn.
  • 20 degree slope on knobs and roses minimizes attachment points.
  • Knob/thumbturn recessed to reduce vertical gaps.
  • Available in US32D satin stainless steel finish, and 630AM antimichrobial finish.
  • Concealed mounting, tamper-resistant.
  • Conversion trim kit available for existing installations.
  • Available for most L9000 series functions.
  • UL listed – 3 hours.
  • ANSI/BHMA Grade 1.

You can download the catalog cut for this product here: Anti-Ligature Catalog Cut, and if you have any questions, just leave a comment and I’ll post the answers.  Schlage is currently exploring an anti-ligature lever, so I’ll post about that when the details are available.

14 Responses to “Anti-Ligature Knob”

  1. cda says:

    I do not enforce ada, but is the knob ada compliant???

  2. Bob Caron says:

    Anti-ligature requirements have been popping up a lot lately. There’s a lot of V.A. Hospital renovation work going on and we just supplied anti-ligature thumb-turns for existing mortise dead locks. We used Town Steel products there. Accurate locks makes some nice retrofit anti-ligature products but they are more expensive. Sargent is also redesigning their PT trim, push/pull for mortise locks. It’ll be a few more months before that come out. Pretty much everyones hospital style latches for mortise locks has a large flat surface at the top edge of the trim. If Glynn-Johnson isn’t already working on that for their push/pull trim, maybe a nudge from you might get it in the works.

    • Joshua says:

      We are in the spec for VA Correct Adult Psychiatric Unit Deficiencies, VAMC Spokane. For Door Switch ONLY!!

      We are in the checklist for the VA hospitals

      This already been used to save lives, And Has Been Install for 4 Years.

      The only anti-ligature patented over the door alarm device.

  3. ALIN S says:

    i have an idea for a no ligature lever, if you apply so much pressure to it the lever pulls off and an alarm is sounded.

  4. Lori says:

    This knob is definitely not accessible, but I’m doing some research on whether a room that would typically have this type of hardware is required to be accessible. I hope to have more info to post here shortly.

    From what I’m hearing, Schlage will have an anti-ligature lever available fairly soon.

    – Lori

  5. Monica says:

    Accurate has presented the Crescent Handle ( as a solution for anti-ligature and ADA compliance.

  6. Sarah Nosal says:

    Marshall Best Security has some very nice antilig products. They do have both Mortise and Cylindrial locks with LEVER HANDLES to help you meet the ADA. We just had to supply them for some assisted living. The tenants couldn’t use the knobs, but the levers worked great. This is definilty a growing market.

  7. Monica says:

    The safety lever system is great for ADA compliance but will still present the opportunity of creating a ligature point.

    • Mark Berger says:

      Stanley has the widest selection of ant-ligature lever locks and functions. Knobs are not favored by facilities.

  8. Uriah says:

    I second that! Stanley not only has the best quality ligature-reistant lever set but has come out with an over-the-door alarm system to reduce the risk of patients harming themselves using the top of the door as a ligature point. These both are recommended by the VA.

    • Joshua says:

      The Door Switch provides a solution. This safety product is an over-the-door pressure switch that activates an alarm when patients try to use the door as a ligature point.

      This has already been used to save lives.

      The only anti-ligature patented top door alarm device.

  9. Anna says:

    Thanks for the link, Uriah! I’m not sure if anyone else has this same experience, but our nurses had trouble opening the knobs shown in the picture above (particularly when hands were full or greasy from the pizza or whatever at lunch.)

    Our facility tried a few of the Stanley SPSL levers that you mentioned above, and loved them. Now apparently we’ve got plans to switch all the knobs to these levers over time, since they are ADA + anti-ligature + easy to open.

    We have a local Stanley Service tech that did the installation on the levers and a few of the SEDA units (door alarms). He was very nice and helpful… he gave me his number, but I think it was just work-related. 😉

  10. Graham says:

    Brilliant, we will include these in our next proposal! We have been supplying alot of anti ligature products to VA hospitals across the USA including door knobs and TV housings (



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