Health and Safety Forum

Knowledge Network | Health and Safety Forum

Tree workers working near de-energised HV lines

  • Tree workers working near de-energised HV lines

    Posted by bcoradinepowernet-co-nz on 2 August 2022 at 11:38 am

    Hi Team, just a quick question about what your organisations are doing regarding third-party tree workers working near de-energised HV lines. My question is, what process, safety measures, or permitting system does your organisation employ for this situation?

    Kind Regards, Brett Coradine

    Stephen Albrecht replied 2 years, 3 months ago 3 Members · 2 Replies
  • 2 Replies
  • Stephen Small

    Member
    2 August 2022 at 11:46 am

    Hi Brett

    Our response would be completely different depending on whether the de-energisation was specifically for the third-party tree workers, or if we were undertaking de-energised work ourselves and they took advantage of our outage.

    feel free to ring and discuss.

    Cheers

    Stephen

    0275558870

  • Stephen Albrecht

    Member
    3 August 2022 at 3:06 pm

    Hi Brett,

    MainPower’s Network Operations and Control Centre has advised:

    It all hinges on how “near” to the HV lines they are.

    The main situations are as follows:

    Work inside the ‘close worker zone’:

  • Lines must be isolated.
    Access permit held by a competent person (could be staff or contractors);
    the cost of this is charged to the third-party vegetation contractor, if
    they are not competent to hold access (currently we have none who are
    competent to that level).
  • Work outside the ‘close worker zone’:

  • Work can be completed
    under a Close Approach Consent, the specified safety distance must also be
    outside the close worker zone (and therefore well outside the MAD).
  • In some cases, we may
    choose to “de-engergise for safety” in case we see increased risk of trees
    falling clear of the workers and into lines. Third party vegetation
    workers must operate under a Close Approach Consent remain outside the
    specified safety distance, which must also be outside the close worker
    zone (and therefore well outside the MAD). This is different from an HV
    isolation. Power is off for safety, but no permit is applied and
    third-party workers must treat lines as live at all times.The question is unclear, as it all hinges on how “near” to the HV lines they are.

    The main situations are as follows:

    Work inside the ‘close worker zone’:
    – Lines must be isolated. Access permit held by a competent person (could be staff or contractors); the cost of this is charged to the third-party vegetation contractor, if they are not competent to hold access (currently we have none who are competent to that level).

    Work outside the ‘close worker zone’:
    – Work can be completed under a Close Approach Consent, the specified safety distance must also be outside the close worker zone (and therefore well outside the MAD).
    – In some cases, we may choose to “de-engergise for safety” in case we see increased risk of trees falling clear of the workers and into lines. Third party vegetation workers must operate under a Close Approach Consent remain outside the specified safety distance, which must also be outside the close worker zone (and therefore well outside the MAD). This is different from an HV isolation. Power is off for safety, but no permit is applied and third-party workers must treat lines as live at all times.

  • Regards

    Stephen

Log in to reply.