Trench shields are an important, potentially lifesaving, part of kit on the job. Choosing the right one to protect your team in the trenches is important. But trench safety doesn’t stop there. You need to be on the front foot.

Changes on site and accidental damage can compromise the structural integrity of a trench shield. That means inspections are vital for compliance as well as safety.

How often should trench shields be checked?

Ideally shields (and parts including pins) should be checked each day, before the work starts on site. And, after any major events during the working day (e.g. heavy rain, earthquakes, landslides etc).

Who should check shields?

It needs to be an experienced, competent person (who that is will vary from site to site, depending on the job’s size and complexity). This could be the site engineer in charge of checking the safe and correct installation of the shields.

How does damage to trench shields happen?

Huntley, from the Guardian team, says when 20 tonne diggers are being used to move trench shields around, damage may occur accidentally. “Large diggers can leave little holes or dents.” But they’re not the only factor. Extreme weather, changes in the soil profile, and the stress of daily work, and wear and tear also need to be considered.

It's important to avoid incorrect use of a shield, for instance, using a shield with no front cutting edges as a drag shield.

What should you look for, checking a trench shield for damage?

• Assess the panels on both sides. Are there any punctures or dents?

• At the end beams, check for any bending or deflection of the shield panels (greater than 2.5cm could be a problem).

• Ensure holes in strut receivers are still round, and that there are no stress cracks.

• Check struts for straightness, absence of dents, and round pinholes without cracks.

• Confirm pins and keepers are in place and are fit for purpose, straight and not dented or badly scratched.

Cosmetic versus structural damage

Wear and tear are a constant in construction and infrastructure: minor scratches to trench shields will not generally impair structural integrity but regular inspection is still vital. Whereas if the damage is structural like a bent panel or a whole punctured through the shield, is not fit for use and will need repairing to a certifiable standard.

Storage

Proper storage and handling will mitigate damage. Always clean and let trench shields dry between uses. Horizontal storage, undercover, if possible, is preferable. Avoid using inappropriate lifting equipment which could perforate, drop, or otherwise damage the shields. As an extra safety measure, you can strap the shields together in groups of three when stacked to stop them from slipping.

What to do if there’s damage

Log it immediately. Take photos, including the serial number of the trench shield and get in touch with the manufacturer, or company you’re dealing with.

Do not use the trench shield. Damaged shields can end in trench collapses and, worst case, loss of life. Seehttps://www.transquip.co.nz/blog/trench-shield-safety-training-course for our training course, to help you use and inspect trench shields properly and save lives in trenches.

Who can repair trench shields?

Only a certified welder should be working on trench shields. They know what they’re doing and that’s what you need when people’s lives are at risk.

What’s the advantage of hiring or buying a pre-inspected trench shield?

In short – you know what you’re getting. If the shield has been cleaned, stored, and inspected by experts it’s going to perform as per its ratings.

What is a trench shield’s likely lifespan?

Treated respectfully, and looked after correctly, shields can perform effectively for up to 20 years under normal working conditions.

For the regulations you need to meet, check out New Zealand's safety regulations on NZTA https://worksafe.govt.nz/topic-and-industry/excavation/excavation-safety-gpg/

For an introductory trench safety course visit https://www.transquip.co.nz/blog/trench-shield-safety-training-course .

And for the full Guardian range (purchase or hire) click here https://www.transquip.co.nz/search?keywords=guardian%20trench%20shields.

To sum up

Inspect. Daily. With trench shields, never leave anything to chance.

Keep your working site looking professional and protect your people. If you have any questions at all, call us.

Contact Information: For further inquiries or detailed guidance on aluminium trench shield inspections, please contact Huntley Townshend ht@transquip.co.nz PH: +64 21 983 139 or Harley Bruce harley@transquip.co.nz

Disclaimer: The information provided in this blog is for educational purposes only. It is essential to consult with certified professionals and adhere to local regulations and manufacturer guidelines when inspecting and maintaining trench shields. We are not liable for any failures or damages resulting from the use or inspection of trench shields.