Handling hop dust safely and spotting hop allergies at work

Why hop handling deserves attention

A modern hoppy brewpub can handle many kilograms of pellets a week. Pouring them creates fine dust that drifts into the air and onto skin. Most brewers never have a problem. Some develop irritation or allergy over months or years of exposure. Once that happens, it tends to get worse with each contact.

Dry hopping also usually happens at the top of a fermenter. That means working at height, often over an open manway on a tank that is actively producing carbon dioxide. Our guide to brewery safety culture covers the wider habits that make jobs like this safe.

Hop dust and breathing

Pellet dust is fine and can be breathed in easily. In the short term it can cause sneezing, coughing and irritated eyes. With repeated exposure, some people become sensitised and develop allergy symptoms such as a runny nose, wheezing or tightness in the chest whenever they handle hops.

Simple controls make a big difference:

• Pour pellets gently from a low height rather than shaking bags out at arm's length.
• Open bags with a clean cut instead of tearing them, which throws dust into the air.
• Wear a well-fitting dust mask rated FFP2 or N95 when handling large quantities.
• Wear safety glasses, especially when working above head height.
• Clean up spilled pellets and dust with a vacuum or damp cloth, not compressed air.

Skin reactions

Handling hops can also irritate the skin. Some people notice redness, itching or a rash on the hands, wrists and forearms after handling hops, especially whole cones and fresh hop material. Hop pickers have reported this kind of reaction for a long time.

Wear nitrile gloves and long sleeves for dry hopping and for cleaning out hop debris. Wash hands and forearms after the job. Anyone who notices recurring skin or breathing symptoms should see a doctor and tell them about their work, rather than ignoring it. A brewer with a confirmed hop allergy may need adjusted duties, which is a matter for the employer and a medical professional, not guesswork.

Carbon dioxide at the manway

An actively fermenting tank produces large volumes of carbon dioxide. CO2 is heavier than air and collects at the top of an open manway, in the tank and in low spaces around it. Leaning over an open manway and taking a breath can cause dizziness or worse.

• Never put your head into or directly over an open manway.
• Use a closed dry hop port, a hop dosing device or a sealed vessel where possible.
• Make sure the brewery is ventilated and that CO2 monitors are fitted and working in enclosed areas.
• Never enter a tank without a proper confined space procedure.

Our guide to CO2 in the brewery covers monitoring and ventilation in more detail.

The hop geyser

Here is the floor detail every new brewer should learn before their first dry hop: adding pellets to beer that holds dissolved CO2 can cause sudden, violent foaming. The pellets provide thousands of nucleation points. The gas comes out all at once. Beer and wet hops can shoot out of the manway towards the person adding them.

Reduce pressure in the tank gently before opening. Add hops slowly, a little at a time. Stand to one side rather than directly over the opening. Wear eye protection. On a carbonated tank, use a pressurised dosing vessel or a closed system rather than an open manway.

Working at height

Dry hopping usually means climbing to the top of a fermenter. Use a stable platform or a proper ladder secured at the top. Keep three points of contact while climbing. Do not carry a heavy bag of hops up a ladder in one hand. Lift hops up separately or use a platform where you can stand with both hands free.

Wet hop pellets and beer on the platform are slippery. Clean them up straight away.

Building it into the job

Write dry hopping into a standard procedure that includes personal protective equipment, venting the tank, CO2 checks and the order of steps. Train every new team member on it and walk through it together the first time. A procedure written down is easier to follow consistently when the brewery is busy.

Common questions

Can you be allergic to hops?

Some people develop skin or breathing reactions to hops after repeated handling. Anyone with recurring symptoms at work should see a doctor and mention their job.

Why does beer foam out when dry hopping?

Hop pellets give dissolved CO2 many points to form bubbles, so gas leaves the beer suddenly. Reduce tank pressure first and add hops slowly.

What mask should brewers wear for hop dust?

A well-fitting FFP2 or N95 dust mask is a sensible choice when handling large quantities of hop pellets.