Collisions and emissions reporting

Helping procurers understand and accelerate improvements in supplier performance

CLOCS mission is to ensure the safest, leanest and greenest construction vehicle journeys. Its ethos continues to be to drive measurement and continuous performance improvement by all parties – particularly by leveraging the power of regulation and procurement that should always seek to create the right commercial and physical conditions for all parties to perform at the highest levels.

The CLOCS Standard states that:


Clients/principal contractors shall obtain from all regular or significant project or supply chain partners their annual collisions and emissions performance information, and where appropriate, obtain a credible improvement plan.

Performance shall be reported, per 100,000km travelled, for the most recently formally reported 12-month period in last 18 month (to minimise reporting burden).

Collisions shall be reported under:

  • fatal
  • serious injury
  • minor injury
  • near miss (optional)

Emissions shall be reported under:

  • CO2
  • NOX (NO + NO2)
  • PM10 (and PM2.5 if available)

Clients/principal contractors shall determine which contractors/suppliers are ‘significant’.

Clients/principal contractors should obtain from the worst performing quartile of their supply chain (by collision or emission performance), a credible performance improvement plan.

Where specific significant issues are identified, clients/principal contractors shall obtain and monitor an urgent action plan to prevent recurrence on any current or future project they can reasonably influence.

Principal contractors should proactively report all relevant annual performance data and improvement plans to their client(s).


The guide available below is designed to help all parts of the sector better obtain and understand the level of collisions and emissions in organisations they are procuring and in the wider sector, and importantly, to work collaboratively with those organisations to improve the performance of all.