Do I need ear defenders, and how loud is too loud?

Hearing damage from DIY is easy to dismiss because nothing hurts and nothing changes on the day. What actually happens is that a small amount of irreversible damage accumulates each time, and the effect appears twenty years later as difficulty following conversation in a noisy room. The tools involved are ordinary ones, and the protection costs very little.

Safety

Step by step

1. Use the arm's-length test.If you have to raise your voice to be understood by someone an arm's length away, the noise is at a level where protection is warranted. It is a crude test and it correlates well, and it needs no equipment.
2. Assume every power tool qualifies.Circular saws, mitre saws, planers, routers, angle grinders, SDS and hammer drills, impact drivers, petrol mowers, strimmers, chainsaws and pressure washers are all loud enough to matter. So is hammering in a small hard-surfaced room.
3. Understand that time matters as much as level.Exposure is a product of loudness and duration, and the trade is steep — a small increase in level halves the safe duration. Five seconds with an impact driver is not the same problem as an afternoon with a router, but both count towards the same total.
4. Read the SNR figure.The single number rating on the packaging is the approximate reduction in decibels the protector provides in ideal conditions. Real-world performance is meaningfully lower, particularly for plugs that are not inserted properly.
5. Do not over-protect either.Choosing the highest SNR available for a moderately noisy job cuts you off from speech and warning sounds, which makes people take the protection off. A moderate SNR you keep on beats a high one you remove.
6. Insert foam plugs correctly.Roll the plug into a thin cylinder, reach over your head with the opposite hand to pull the top of the ear up and back, insert well into the canal, and hold it while it expands. A plug perched in the outer ear provides a fraction of its rating.
7. Check the seal on muffs.The cushions must seal all round. Long hair, a hat, a hood, safety glasses arms and a mask strap all break the seal, and a small gap costs a large proportion of the protection. Thin-armed safety glasses exist for this reason.
8. Put them on before you start.The loudest part of using a tool is often the first cut, and the habit of protecting after the first noise is how most exposure happens. Protection goes on with the eye protection, before the tool is picked up.
9. Protect other people too.Anyone in the room or the garden while you use a chainsaw, a strimmer or a grinder is exposed as well, and children's hearing is more vulnerable. Move them or protect them.
10. Treat tinnitus as information.Ringing or a muffled feeling after a job means that job caused damage. It usually settles, and the damage does not. Change what you are doing rather than waiting for it to stop happening.

Tips

• Keep a pair of plugs in every toolbox and a pair of muffs hanging where the noisy tools live. Availability, not intention, decides whether they get used.
• Muffs and safety glasses fight each other. Thin-armed or cord-style safety glasses, or plugs instead of muffs, solves it.
• Electronic defenders that pass through speech are worth the money if you work with someone else, because the alternative is repeatedly taking them off to talk.
• Petrol garden machinery is often louder and used for far longer than workshop tools. A whole afternoon strimming is one of the highest exposures most people get.

Common mistakes

• Wearing earbuds with music instead of protection — They are not rated, and competing with tool noise means raising the volume, so you receive both the tool and the music.
• Perching foam plugs in the outer ear — Foam plugs work by sealing the canal. Not inserted properly, they deliver a small fraction of their rating and feel like they are working.
• Only protecting for the loud jobs — Damage is cumulative across everything. Moderate noise for a long period does as much harm as a brief loud burst.
• Taking defenders off to hear what someone is saying — It happens exactly when the tool is running. Level-dependent defenders or plugs solve the underlying problem.

Alternatives

• Foam earplugs: Rolled down and inserted into the ear canal, expanding to seal. Cheap, extremely effective when inserted correctly, and easy to carry so they are actually available. Most people insert them badly, which halves their effect.
• Banded or corded plugs: Plugs on a light band or cord, quick to take in and out and hard to lose. Convenient for intermittent work where you keep stopping to check something.
• Ear defenders (muffs): Cups sealing over the whole ear. Easier to put on and take off correctly than plugs, so in practice they often deliver better real-world protection. Hot in summer and awkward with glasses, because the spectacle arm breaks the seal.
• Electronic or level-dependent defenders: Muffs with microphones that pass through quiet sound and cut loud sound. Expensive but genuinely useful, because you can hear speech and warnings while remaining protected — which is the reason people take defenders off.
• Music headphones or earbuds: Not hearing protection. Passive isolation is not rated, and the natural response is to turn the volume up to compete with the tool, which adds a second noise source directly into the ear.

Questions people ask