A sneeze guard — food guard, breath guard, or food shield in various catalogues — is the transparent barrier positioned between customers' faces and displayed food, intercepting the droplets that talking, coughing, and leaning would otherwise deposit on an open counter. The panel is angled or positioned so the direct line from a standing customer's mouth to the food is blocked, while servers or guests still reach the food beneath or beyond it.

As for the law: virtually every food-safety regime requires displayed, unpackaged food to be protected from contamination, and names effective barriers as the means. The US FDA Food Code makes the intercept explicit for self-service; EU hygiene regulation states the protection duty with the barrier as accepted compliance; and national codes across other markets follow the same logic. In practice: buffets, salad bars, carveries, bakery and deli displays, market hot counters — any unwrapped food presented where customers stand — should assume a guard is required, and inspectors treat a missing or badly-positioned one as a violation, not a style choice.

The operational point behind the rule: the guard is the one hygiene control that works without anyone's compliance — no behaviour, training, or reminder involved. It simply stands there all service, which is why regulators like it and why cutting it is the wrong economy.

The families, by how the food is accessed:

1. Self-service guards — the buffet and salad-bar standard: a panel angled toward the customer with the access gap below, so guests reach under to serve themselves while the panel intercepts the breathing zone. Single-tier for one row of pans, double-tier for deep counters.
2. Full-service guards — for staffed carveries, delis, and hot counters: the panel sits more vertically with a pass-over or pass-under at server height; customers point, staff plate. Protection extends higher because customers lean toward conversation.
3. Adjustable and multi-position guards — pivoting panels on ratcheted or gas-strut arms that convert a line between self- and full-service (breakfast buffet by day, staffed carvery by night). The moving joint is the part to buy well.
4. Portable and free-standing shields — weighted-base units for banqueting tables, outdoor events, and pop-up lines; no counter fixing, storable flat.
5. Display-case hybrids — guards integrated with refrigerated wells and heat lamps as one merchandising unit.

Fit is decided by three measurements: counter depth (the panel must cover the food zone, typically reaching the centre line of the furthest pan), service style (who reaches, from which side), and customer profile — school and family venues position for shorter breathing zones, which changes heights meaningfully. Where a line changes character between services, the adjustable family earns its premium quickly.

Both meet the hygiene requirement; they split on optics, durability, and duty:

Tempered glass is the premium standard for permanent installations: scratch-resistant (survives years of nightly cleaning without hazing), chemically indifferent (any sanitiser, any degreaser), heat-tolerant near lamps and hot wells, and optically flat — food looks best behind it, which matters when the display IS the sales pitch. Tempering makes breakage rare and safe-patterned. Its costs: weight (mounts and counters must carry it), higher price, and edge-chip care during any disassembly.

Acrylic (and polycarbonate) is light, affordable, and shatter-resistant — the material for portable shields, banquet and outdoor lines, schools, and anywhere panels are handled, moved, or stored between uses. Polycarbonate adds near-unbreakability for rough duty. The trade-offs are surface-level, literally: acrylic scratches under paper towels and gritted cloths, clouds under alcohol- and ammonia-based cleaners (soapy water and microfibre only), and hazes faster near heat lamps — figure on panel replacement every few years in hard service versus glass's decade-plus.

The venue logic that follows: fixed lines and premium displays → tempered glass; mobile, temporary, high-knock, or budget lines → acrylic, bought with spare panels. Mixed estates do both — glass on the flagship buffet, acrylic in the function kit. Whichever material, specify smooth polished edges (cleanability and safety), and confirm panel thickness suits span — thin panels flex, and a wobbling guard reads as flimsy hygiene to the very customers it is reassuring.

The regulatory logic: the panel must intercept the straight line between an average standing customer's mouth and the exposed food. The widely-used engineering of that logic — drawn from US NSF/ANSI standard 2 and mirrored in practice elsewhere — works to a customer breathing zone at roughly 1,350–1,500 mm (53–59 in) above the floor, and requires the panel to block the direct path from that zone to every exposed pan.

In practical dimensions for a standard 900 mm-high counter:

• Self-service: panel leading edge typically 350–450 mm above the counter, angled 20–40° toward the customer, with the serve-under gap of roughly 215–330 mm (8.5–13 in) — low enough to intercept, high enough for plates and spoons.
• Full-service: more vertical glazing carried higher (customers lean and talk over it), with the pass gap positioned for staff, not customers.
• Coverage: the panel's horizontal reach must shadow the food zone — the FDA/NSF test is that food sits within the protected envelope, commonly summarised as the panel edge extending past the food's leading edge; deep double-row counters need second tiers or deeper panels.
• Special populations: where the average customer is shorter — schools, children's buffets — the intercept height drops and panels mount lower; the breathing-zone principle, not the adult dimension, is the rule.

Two compliance realities: adjustable guards must satisfy the geometry in every position they operate in, not just the showroom pose; and local codes (and franchise standards) may bind specific numbers — where an inspector's jurisdiction publishes dimensions, those override generic guidance. Buying certified food-shield product lines (rather than improvised panels) is the shortcut: their geometry is pre-engineered to these tests, and the paperwork answers the inspector before the question.

A smeared guard undoes its own purpose — customers judge the food through it — so cleaning is daily and material-specific:

Both materials, every service day: clean both faces (the customer side carries fingerprints and breath film; the food side carries steam residue and splatter), plus the posts, brackets, and the counter seam beneath — the guard's mounting line is a classic grime trap inspectors probe. Clean when panels are cool, never over the food (dismount or clean before stocking), and finish with a dry microfibre pass so the panel disappears optically.

Tempered glass: warm water with detergent or standard glass cleaner, microfibre or squeegee, any sanitiser the kitchen runs. Degrease lamp-adjacent panels weekly with a stronger alkaline cleaner; baked-on haze wipes off glass that would have permanently clouded acrylic.

Acrylic and polycarbonate: soapy warm water and microfibre ONLY — no ammonia glass cleaners, no alcohol wipes, no abrasive pads, no dry paper towels (each is a documented hazing or scratching route). Anti-static acrylic cleaner reduces the dust cling that makes plastic guards look dirty by mid-service. Light scratches respond to acrylic polish; cloudy panels are replacement candidates, which is why acrylic estates keep spares.

The habits that extend panel life: lift-off panels come off for cleaning rather than being scrubbed in place at awkward angles (in-place scrubbing is where edge chips and bracket strain come from); hinged panels get their pivots wiped and checked while open; and the cleaning caddy for the line carries the acrylic-safe products separately labelled — the single most common damage source is the well-meaning closer using the glass spray on the plastic guard.

Ten minutes a day total, and the barrier stays what it should be: legally present and visually absent.

Yes — portable shields are a legitimate, code-recognised solution wherever the serving line itself is temporary, and the events trade runs on them. The requirements do not relax because the counter folds: the same breathing-zone geometry, coverage, and cleanability apply to a weighted-base guard on a banquet table as to a bolted one on a marble counter.

What separates working portable guards from wobbling liabilities:

1. Stability engineering. Weighted or wide feet that resist the bump of a chafing dish swap and the lean of a curious guest; on outdoor duty, wind — a tall acrylic panel is a sail, so outdoor units want lower profiles, heavier bases, or clamp fixing to the table. A guard that can be knocked into the food is worse than no guard.
2. Tool-free assembly that stays assembled. Slot-and-lock posts and captive fittings survive the hundredth build; thumbscrew-everything designs shed parts by mid-season. Number the panels and posts per unit — mixed kits assemble crooked.
3. Panel material realism: acrylic or polycarbonate, always, for transport duty — with edge protection in the transit crates and the spare-panel discipline that acrylic demands. Padded cases pay for themselves in one season.
4. Height adaptability: banquet tables (760 mm) sit lower than counters, so the guard must still reach intercept height from the lower deck — buffet-specific portable lines are dimensioned for exactly this; generic counter units often are not.
5. The full-line audit: every exposed pan on the temporary line needs coverage, including the carving station and the dessert flank added at the last minute — the classic event-inspection failure is the one unguarded chafer at the end.

Operationally, treat portables like the event asset they are: cleaned and inspected at pack-down, stored assembled-adjacent (panels flat, posts bagged), and counted like linen. A hire-grade portable kit maintained this way passes the same inspection the built-in line does — which is the entire point.

Work pan-by-pan, then buy in modular sections:

The coverage rule: every exposed food well must sit inside a panel's protected envelope. Guards are sold in standard section widths — commonly 900 mm, 1,200 mm, 1,500 mm (3, 4, 5 ft) — and a line is built by butting sections post-to-post. Measure the actual food zone (first pan's leading edge to last pan's trailing edge), not the counter: an 3.6 m counter with 3.0 m of wells needs 3.0 m of guard positioned over the wells, and the uncovered plating zone at the end is fine — it holds plates, not food.

Junctions and gaps: sections should meet with minimal gaps (panel-to-panel gaps above a food well defeat the geometry); corner and 90° junction posts exist for L- and U-shaped lines — specify them rather than improvising a mitred meeting of two straight runs. Island buffets served from both sides need double-sided guards (panels both faces) or centre-mounted two-way designs; a single-face guard on an island protects one queue and performs theatre for the other.

Depth: single-tier guards shadow one row of full-size pans; two-row-deep counters need either deeper cantilevered panels or a second tier — check the manufacturer's stated protected depth against your pan layout, including the drop-in wells' true positions.

Ends matter: the exposed ends of a line are reach-around routes; end panels (returns) close them on self-service lines and are increasingly expected by inspectors.

The buying strategy: draw the line's pan layout, mark service style per zone (self vs staffed), and map sections onto it — most suppliers' modular systems then translate the drawing into posts, panels, and returns directly. Over-covering by one section is cheap insurance; a line that grows a dessert station next season will use it.