In brief
Even a small hand tool falling from height can be fatal for someone working below. The Regulation on OHS in Construction Work requires collective protection against falling objects first; preventing hand tools and materials from falling, preventing access to the danger zone or building covered walkways, not throwing materials to the ground and ensuring hard hats are worn are all part of this protection. The order of measures is preventing falls at source, catching what falls, closing off the area below and, finally, wearing a hard hat.
Falling object risk: a small tool, a lot of energy
A spanner that is not attached to the belt of a tradesman working on a fourth-floor scaffold slips from his hand, falls over the edge of the scaffold platform and hits someone working in the material area on the ground. Nobody on the upper floor is hurt; the accident happens entirely below. Falling object risk therefore concerns not the "person working at height" but everyone below and around them.
The impact of a falling object increases with its mass and the height it falls from. When a hand tool falls from several floors up, the energy it carries at the moment it hits the ground can reach a level that exceeds what a hard hat can withstand. Moreover, objects do not always fall straight: they can hit a scaffold tube or the facade and ricochet to an unexpected point.
The sources of falling objects on a construction site fall under a few headings:
- Hand tools and small parts such as bolts, nuts and clamps,
- Material stacked close to the edge of a scaffold platform or slab,
- Pieces breaking off and debris during dismantling and demolition,
- Parts slipping or breaking off a load carried by crane,
- Sheets, packaging and light material lifted by the wind.
What does the Regulation on OHS in Construction Work require?
Annex II, item 3.1.3 of the Regulation on Work Equipment also requires that, unless technically necessary, nobody is under a suspended load during lifting operations, and that loads are not moved over unprotected places where employees may be present. The general principle in Art. 5 of Law No. 6331 on Occupational Health and Safety is the same: collective protection measures take priority over personal protection measures.
Order of measures: prevent the fall first, then the impact
Think about the measures in this order; each step covers where the previous one falls short.
| Step | Aim | Example measures |
|---|---|---|
| 1. Elimination | Reduce the amount of work at height | Pre-assembling elements on the ground, using fewer parts and tools at height |
| 2. Prevention at source | Stop the object from falling | Toe boards, mesh panels on edge protection, tool tethers, lidded tool bags, keeping stacks away from edges |
| 3. Catching | Hold what falls | Safety netting, debris netting, scaffold facade netting, catch platforms |
| 4. Control of the area below | Nobody underneath | Exclusion zones, covered walkways, not working in the same vertical line in the work schedule |
| 5. Personal protection | Against residual risk | Hard hat; hard hat with chin strap for those working at height |
The most common mistake we see on site is starting at step five: "Everyone wears a hard hat, that's enough." A hard hat protects against a light object falling on the head; it does not protect against a clamp falling on the shoulder, a tube ricocheting in or a heavy part.
Toe boards and edge protection
A toe board is a board fitted at floor level along the edge of a platform or slab that stops tools, materials and parts kicked by feet from sliding over the edge. Under Annex 5, Part (B) of the Regulation on OHS in Construction Work, for Class A edge protection:
- The top edge of the top guardrail is at least 1 m high,
- The toe board is at least 15 cm high,
- The gap between guardrail elements is at most 47 cm, and at most 25 cm in systems with vertical members,
- Edge protection is inspected after installation and at least once a week.
The toe board is the cheapest and most often forgotten part of fall prevention. A board not refitted after scaffold dismantling or alteration is the first thing to check in the weekly inspection; you can plan weekly inspections with the OHS calendar. On platforms where material is stacked, mesh panels or grilles are added to the guardrail for small parts that could pass through the guardrail gaps. For the full scaffold inspection, see our articles on scaffold inspection and tagging, and for floor openings, floor openings and edge protection.
Tool tethers: which tool, where and how?
A tool tether (tool lanyard) prevents a tool used at height from falling if it slips from the hand. In practice, these rules work:
- Which tools? Every tool used at height with work going on underneath is tethered; especially spanners, hammers, drills, measuring instruments and radios.
- Attachment point: Light tools can be attached to a wrist strap or a suitable attachment point on the safety harness. Heavy tools are attached not to the person but to the structure or a fixed point; a falling heavy tool can also unbalance the employee.
- Capacity: According to the manufacturer's information, the weight the tether and connector can hold must be greater than the weight of the tool. In the USA, the ANSI/ISEA 121 standard is used for these products.
- Hand-to-hand transfer: When a tool is passed from one person to another, the receiver first attaches it to their own tether, then the giver detaches it.
- Small parts and lifting up: Bolts, nuts and clamps are carried in a lidded bag or bucket. When material is raised by rope, bucket or crane, the bucket must be closed and secured.
Safety netting and exclusion zones
Safety netting is used for two different purposes, and the two should not be confused. Safety nets used against people falling are selected and installed according to TS EN 1263-1 and TS EN 1263-2; the regulation also lists safety nets among collective protection measures. Fine-mesh debris nets and scaffold facade netting, on the other hand, catch debris and small parts but are not designed to hold a person. Fitting netting or sheeting to the scaffold facade increases the wind load; confirm with the company that erected the scaffold that it has been designed and tied in for this load.
There is no fixed distance in the legislation for an exclusion zone; the danger zone is determined according to the work. When deciding, consider:
- Working height and the shape of material that may fall: sheets and light material are blown far by the wind, tubes and sections ricochet.
- Wind: In strong winds the danger zone widens; some work is stopped. On this, see our article on cranes and working at height in strong winds.
- Need for access: If building entrances, walkways and material areas fall within the danger zone, a covered walkway or canopy is built.
The excluded area is bounded not with tape but with a free-standing barrier; at entrances there are mandatory signs showing warnings and the use of hard hats. Making sure different subcontractors do not work in the same vertical line, one above and one below, is resolved in advance in the work schedule; for coordination between employers sharing the same area, see our article on multiple employers in the same work area.
Mandatory hard hats and correct use
The hard hat requirement on construction sites is based on the provision in Annex 4 of the Regulation on OHS in Construction Work that "suitable head protection is provided and its use is ensured", and on the Regulation on the Use of PPE. A hard hat is worn in every area where the risk assessment identifies a falling object risk; visitors and people entering the site briefly are also covered by this rule.
For correct use:
- Industrial hard hats conform to TS EN 397; for people working at height and working bent over, a chin strap is used to keep the hard hat on the head.
- A hard hat is replaced if it is cracked, deeply scratched or has taken an impact, or if its harness is worn; the date of manufacture and the service life recommended by the manufacturer are tracked.
- Holes are not drilled in the hard hat, and paint and adhesive are not applied to it.
We covered selection and service life in detail in our article on hard hat selection and service life. To check falling object measures across the site on the weekly round, you can use the items in our construction site OHS checklist.
In construction projects, putting exclusion zone plans, edge protection inspections and tool tethering rules in place on site is work we carry out in Bursa and the surrounding provinces under our OHS specialist service.
Frequently Asked Questions
How high should a toe board be?
Under Annex 5, Part (B) of the Regulation on OHS in Construction Work, the toe board in Class A edge protection is at least 15 cm high. The top guardrail is at least 1 m high, and edge protection is inspected after installation and at least once a week.
Is wearing a hard hat mandatory on a construction site?
Yes. The Regulation on OHS in Construction Work requires employees on the construction site to be provided with suitable head protection and its use to be ensured. Visitors and people entering the site briefly also wear hard hats in areas with a falling object risk.
Is a tool tether needed for every tool?
It is needed for every tool used at height where there is work going on underneath. Small parts are carried in a lidded bag or bucket. Heavy tools are attached not to the person but to the structure or a fixed point.
How large should an exclusion zone be?
There is no fixed distance in the legislation. The danger zone is determined through risk assessment based on working height, the shape of the material and the chance of ricochet, wind and the need for access. The zone is closed off with barriers, and covered walkways are built where access is unavoidable.
A certified specialist matched to your hazard class: site inspections, approved logbook, training plan, annual plan and report follow-up.
Bursa SİSTEMER OSGB Technical Team — written from the field experience of our OHS specialists and workplace physicians. Legal information is valid as of the publication/update date; contact us for an assessment specific to your business.