If your system is 5.x or newer, you can already implement misdial prevention in ESA - Do NOT use the method below.

If your system is older, you can stop misdials to 911/9911 using SPN, FLEN and SDRR.  In the following example, callers dialing 9,911 (or 9,11) will route to the 911 center.  However, if they dial any additional digits) the call will be blocked. Test this out on your switch.  There is a slight delay before ringing 911. 

If your system is 5.x or newer, you can already implement misdial prevention in LD24 ESA - DO NOT USE THIS METHOD

If your system is newer than Rls 3 but not yet Rls 5: Get this patch: MPLR20340 - This will set misdial prevention to the default settings (Note you will not see the new MISDIAL_PREVENTION prompt, but subsequent digits dialed, or hangup withing 2 seconds will get fast busy)
 
SPN 911 SPN 11
  • >ld 90
    ESN000

    FEAT net
    TRAN ac1
    TYPE spn

    SPN 911
    FLEN 4
    ITOH NO
    RLI (The RLI for SPN 911)
    DENY 0
    DENY 1
    DENY 2
    DENY 3
    DENY 4
    DENY 5
    DENY 6
    DENY 7
    DENY 8
    DENY 9
    SDRR DENY CODES = 10
    ITEI NONE

 
  • >ld 90
    ESN000

    FEAT net
    TRAN ac1
    TYPE spn

    SPN 11
    FLEN 3
    ITOH NO
    RLI (The RLI for SPN 11)
    DENY 0
    DENY 1
    DENY 2
    DENY 3
    DENY 4
    DENY 5
    DENY 6
    DENY 7
    DENY 8
    DENY 9
    SDRR DENY CODES = 10
    ITEI NONE

(Note For SPN 11, DMI treatment must exist to insert the missing 9)
More on how this works: 

911 misdials occur when a user is attempting to dial a 1+Area Code call and inadvertently dials two "1"s after the 9 for an outside line.  Since the attempt was to call an 11 digit number, the user keeps dialing after the 911 digits and hopes to reach their party.  The 911 center answers and the users hangs up.

With the method shown in the SPNs above, the digits following 9,911 or 9,11 match the SDRR DENY digits and the call is blocked.

If the user simply dials 9,911 or 9,11 and waits, no further digits exist to activate DENY and the call is connected to the 911 center.