Modern power tools address a number of safety and useability issues, but do they meet the industry’s performance spec? Stephen Cousins spoke to tool manufacturers, contractors and site operatives to find out
When Rok’s Aly Miller walked onto the construction site of a new hospital wing in the north of Scotland, he witnessed a scene that made him reconsider his work as a safety coach. He was engulfed by plumes of dust from a hand-held saw operated by a joiner sawing MDF panels. Straining to see through the cloud, Miller noticed that while the joiner and his colleagues wore the appropriate protective goggles and masks, the nearby electricians and plumbers wore no facial protection and were freely breathing in the toxic particles.
‘Although shocking to witness, this situation is typical of many sites across the UK,’ complains Miller. ‘It made me realise that these problems could have been avoided if the dust was removed by the saw itself at source, rather than having to manage its effects. There are several features tool manufacturers should be implementing to improve safety on sites.’
Miller isn’t alone in believing that tool manufacturers are failing to meet the demands of construction’s end users. Other contractors complain about dust and sparks, as well as the safety risks caused by high-voltage cables that snake across sites. Although manufacturers are now producing cable-free, battery-operated alternatives, these are considered heavy and lacking in power. Meanwhile, theft remains a problem as tools lack built-in security and are easily stolen.
On the other hand, manufacturers claim their tools address many of these concerns and are designed in direct response to feedback from end users and site managers. ‘The end user is instrumental to all of our products, this week we’ve got two R&D guys coming over from Japan purely to speak with users on sites and health and safety managers,’ comments Andrew Helby, head of marketing at Makita.
But there’s a third point of view: that of the operatives using the tools on site. The latest innovations might be designed to help contractors meet health and safety legislation and productivity targets, but what are the pros and cons for the skilled workers that use them?
CM visited the Angel Building in north London, where BAM Construct is building an office and retail development for Derwent Valley, armed with some of the latest power tools from Bosch and Makita. Workers with groundwork subcontractor Getjar use skill saws to cut formwork, angle grinders to slice rebar and rotary hammers to break up concrete and drill holes into an existing concrete frame.
After some tests with the new tools (see below), Ianluka Matei and Daniel Budau voiced complaints that battery-operated skill saws and angle grinders didn’t deliver enough power, while a Bosch skill saw was criticised for handling difficulties due to the position of the blade. But perhaps part of the problem was the nature of the test itself. ‘We found it difficult using new tools because you get so attached to your old ones. We’ve become attached to Makita because they’re robust and last a long time,’ says Budau.
Most site managers will be aware of the problems of noise, dust and vibration generated by machinery. ‘Dust is a particular problem when cutting concrete blocks, and with joiners using bench saws and planers,’ says Rok’s Miller. ‘Some machines can be hooked up to an external extraction system on site, but many sites don’t have these, and in practical terms, using equipment that’s supposed to be portable, it really needs to be an integral part of the tool.’
Makita says its woodworking machines are available with built-in extraction, but its angle grinders and rotary hammers need an attachment. ‘We’ve come under pressure from health and safety managers to include extraction, but market take-up for this type of feature is very slow,’ responds Helby. Bosch also has a limited offering, including the GBH223 rotary hammer, which has a removable extraction unit.
Spark capture is another area where site managers would like to see more development. Robert Campbell, group safety manager for Scotland at Rok, says: ‘I haven’t seen much effort going into modifications to capture sparks from angle grinders and skill saws. We do a lot of work with the petrochemical industry, and although there are precautions in place to control the environment, integrated capture is needed in tools.’
The manufacturers, however, point to improvements. Makita’s LC1230 circular saw incorporates a tungsten carbide blade that significantly reduces spark emissions, although none of its products integrate guards that prevent sparks entirely. From the end of this year, most Bosch hand-held saws will incorporate a second guard to fully conceal blades, but it is not considering integrated extraction.
Meanwhile, managers are welcoming the switch to lower voltage battery-powered hand-held technology, which eliminates the need for high-voltage cables. Battery performance has improved significantly in recent years. Developments in lithium ion technology have cut charge times – from an hour to just 20 minutes in the last three years – and usage periods have increased, as have the number of charge cycles per battery.
‘Lithium ion batteries are the way forward. They make for lighter tools, which means less vibration and easier control,’ says Martin Sibley, product manager at Bosch. ‘Our latest tools include a burn-out control, which means that if put under stress, the tool turns itself off before motor or battery burns out.’
On the BAM site at Angel, Martin O’Brien, site manager at BAM, is encouraging the use of cordless products. Ianluka Matei tried out the cordless Bosch GKS 36 V-LI Professional circular saw, using it to cut sheets of ply and lumps of timber to create formwork.
‘I found it less cumbersome than a corded saw when working at height,’ he reports ‘It also came in handy when I was a long way from the power point as cable voltage drops considerably the further away you are,’ he said. ‘But the power was generally low compared to the corded saws and it struggled to cut through several sheets of ply at once.’
But Bosch’s Sibley says many cordless tools are starting to match the performance of their corded equivalents. ‘We have a 36-volt battery drill that can deliver the same force as a 600-volt impact drill,’ he says. Such power savings are proving attractive to the eco-conscious – Makita’s Helby says the use of lower-power cordless devices was a part of the sustainability strategy for the 2012 Olympics.
Contractors using multiple cordless tools might consider installing battery banks – lockers incorporating chargers hard-wired to the mains – which ensure tools and chargers are secure and not left lying around on site. ‘We use them when we start dry lining and fitting out,’ says James Carpenter, a construction manager at Kier Build. ‘They keep the place tidy and you don’t get people continually looking for spare plug points.’
Another issue identified by Rok safety coach Miller is the frequent lack of ‘fail safe’ functions on hand-held tools, which means they can still be used in an unsafe condition. ‘One of our plumbers was injured by a crimping tool with a locking device that didn’t fail safe. Tools should have a mechanism similar to the old nail guns that required positive pressure before they would activate,’ he says.
It’s a disturbing fact that theft of equipment from construction sites is on the rise and hand-held tools are a particular target. ‘We get small power tools stolen all the time, anything that could be used for home DIY,’ says Paul Corner, site manager at Morrison Construction. ‘We usually have a person assigned to look after each tool, and on larger sites they’re locked away each night, but manufacturers should make tools more traceable.’
A glance at manufacturers’ catalogues reveals little progress in this area. Makita has no ‘anti-theft’ devices incorporated into its tools, but is currently exploring the use of swipe cards that allow only authorised users to activate tools. Bosch is also looking at key fob locking systems, similar to those used on cars, as well as integrating tracking devices into tools.
But even this technology could prove impractical on construction sites, where it’s normal for several workers to use the same tool. ‘Security access may be a step too far, it’s hard enough finding your car keys, let alone this,’ says James Carpenter. ‘If a card holder’s off-site or sick, other users will be stuck. It’s also quite common for a chippie to have five or more tools, a jig saw, drills, a planer etc, so lots of cards or security keys would be impractical.’
Despite the concerns voiced here, manufacturers are pushing forward with innovations.
In the near future, users can expect increased efficiency and reduced vibration from hand-held tools, allowing longer periods of use. Batteries will be reduced in size, improving weight and handling, while power and longevity will increase.
But input from all areas of the industry is required to ensure their suitability for construction. ‘The HSE and contractors need to put more pressure on manufacturers to make improvements,’ says Rok’s Campbell. ‘I’ve visited a European factory to try and influence design decisions, but haven’t seen the ideas make it into the tools,’ he concludes. cm
Bosch GKS 36 V-LI // Professional circular saw // cordless
For cutting chipboard, plywood and softwood, formwork boards, sterling board and hardwood. The saw can cut up to 95 chipboards (900 x 19mm) to length with one battery charge. Blade is on the left for improved visibility of the cutting line.
- Price: £479 excl VAT
- No-load speed: 4,000rpm
- Saw blade diameter: 165mm
- Weight (incl battery): 4.8kg
- Battery capacity: 2.6h
- Battery voltage: 36V
- Max cutting depth (90°): 54mm
- Max cutting depth (45°): 38mm
"The battery didn’t deliver enough power for me, I’m used to a larger corded saw"
"I found it less cumbersome than a corded saw when working at height"
Bosch 9” GWS24-230 LVI // Professional angle grinder // corded
For grinding and cutting metal or concrete. Vibration control system reduces vibration by up to 80% in main and auxiliary handles. A ‘kickback stop’ system shuts down the grinder if the disc jams, protecting the user from recoil.
- Price: £168 excl VAT
- No-load speed: 6,500rpm
- Power input: 2,400W
- Weight: 4.9kg
"The power and small blade meant it struggled to get through bunches of rebar"
Makita HR4011C // rotary demolition hammer drill // corded
Dual-function tool for hammering and drilling into concrete. Anti-vibration technology and a handle mounting system isolates the machine from the grip and limits vibration to 4m/s2.
- Price: £914 excl VAT
- Impact energy: 9.5 joules
- Max drilling depth (in concrete): 40mm
- No-load speed: 235-480rpm
- Power input: 1,100W
- Weight: 6.4kg
- Blows per minute: 1,350-2,700
"I’ve been using it to break up concrete and to drill holes into the existing structure for rebar. I preferred the drill bit, which rotates and gives a hammer action"
Do today’s power tools meet industry needs? Text us on 07884 423205
Photographs by Ed Tyler