Stone Masonry AHA (Activity Hazard Analysis / Job Hazard Analysis)

Updated 2026-06-23

A Stone Masonry AHA (Activity Hazard Analysis / Job Hazard Analysis) is the plan that keeps the crew building stone masonry safe through the heavy stone handling and ergonomics, from the masonry-wall stability and collapse, and around the stone cutting silica and mortar contact. Stone masonry lays stone units in mortar to build walls — combining the heavy-stone-handling and ergonomics hazard, the masonry-wall-stability and collapse hazard, and the stone-cutting-silica and mortar-contact hazard. This guide walks through building a Stone Masonry AHA that names the heavy-stone-handling/ergonomics, masonry-wall-stability/collapse, and stone-cutting-silica/mortar-contact hazards and assigns the handling, stability, and silica/contact controls that hold up in the field.

Why stone masonry needs its own AHA

Stone masonry is the construction of walls and structures by laying stone units in mortar — building solid stone walls (ashlar, rubble, and coursed stone masonry) course by course, a heavy, traditional masonry trade. This continues the stone cluster, focused on load-bearing/solid stone masonry (as distinct from stone cladding and veneer). The defining feature is the stone units laid as masonry: stone units are heavy (often heavier and more irregular than block or brick — a pronounced handling and ergonomic hazard), the masonry-wall stability applies (a stone wall under construction can be unstable), cutting/dressing stone generates silica, and the caustic mortar. The hazards combine the heavy-stone-handling and ergonomics (stone units are heavy and often irregular — the handling/ergonomic hazard (lifting and placing heavy, often irregular stone units is physically demanding — a pronounced manual-handling and ergonomic hazard, often heavier than block/brick)), the masonry-wall-stability and collapse (building up the stone wall — the wall-stability/collapse hazard (a stone masonry wall under construction can be unstable/collapse, especially heavy stone walls or unbraced walls)), the stone-cutting-silica and mortar-contact (cutting/dressing stone (silica) and the caustic mortar (cement burns)), and the scaffold- access/falling-material. The heavy-stone-handling/ergonomics and the masonry-wall-stability/collapse justify a dedicated AHA.

Breaking stone masonry into steps

The steps for a Stone Masonry AHA follow the laying:

• Set up scaffold access and material staging (stone staging)
• Mix and spread the mortar (caustic contact)
• Handle and lay the heavy stone units (ergonomics)
• Brace/support the stone wall as it is built (stability)
• Cut/dress stone as required (silica control)
• Manage the handling, stability, and silica hazards
• Point, clean, and cure the stonework
• Complete

Each step carries a hazard, and the heavy-stone-handling/ergonomics, the masonry-wall-stability/collapse, and the stone-cutting-silica/mortar-contact are where the most significant risks concentrate.

The hazards step by step

Heavy-stone-handling and ergonomics

Stone units are heavy and often irregular — the handling/ergonomic hazard (lifting and placing heavy, often irregular stone units is physically demanding — a pronounced manual-handling and ergonomic hazard, often heavier than block/brick). The controls are managing the heavy-stone handling and ergonomics (stone units are heavy and often large and irregular, so lifting and placing them is a pronounced manual-handling and ergonomic hazard — mechanical handling/lifting aids for heavy stone, team lifting, staging stone within reach, good work height, pacing, rotation, and keeping hands out of pinch points when setting heavy irregular stone), and the handling/ ergonomic controls. The heavy-stone-handling/ergonomics is the primary defining hazard — heavy, irregular stone is a pronounced handling/ergonomic hazard. (These follow the manual-handling fundamentals.)

Masonry-wall-stability and collapse

Building up the stone wall — the wall-stability/collapse hazard (a stone masonry wall under construction can be unstable/collapse, especially heavy stone walls or unbraced walls). The controls are stability of the stone wall during construction (a stone masonry wall under construction — especially a heavy solid stone wall — must be stable and, where required, braced/supported, since a fresh or unbraced stone wall can be unstable and collapse), and the wall-stability controls. The masonry-wall-stability/collapse is a defining hazard — a stone wall under construction can be unstable/collapse. (These follow the masonry-wall-stability fundamentals.)

Stone-cutting-silica and mortar-contact

Cutting/dressing stone (silica) and the caustic mortar (cement burns). The controls are silica control for cutting/dressing stone (many stones are high in silica — cutting and dressing stone generates respirable silica — wet cutting, dust extraction, respiratory protection), preventing skin contact with the caustic mortar (gloves, skin protection), and the silica/contact controls. The stone-cutting-silica/mortar-contact is a defining hazard. (These follow the silica and cement-contact fundamentals.)

Scaffold-access/falling-material

The scaffold access and falling material (building from scaffolds, falling heavy stone/tools) carries the access/ falling-object hazard. The controls are safe scaffold access (fall protection, scaffolds rated for the heavy stone loads), falling-object protection (heavy stone falling is especially dangerous — toe boards, controlled access below), and the access/falling controls. (These follow the scaffold and falling-object fundamentals.)

A simple Stone Masonry AHA structure

Heavy-stone handling/ergonomic control and wall-stability/silica safety

A Stone Masonry AHA centers on heavy-stone handling/ergonomic control and wall-stability/silica safety. The heavy-stone handling/ergonomic control addresses the heavy irregular stone — controlled by managing the heavy-stone handling and ergonomics (mechanical lifting aids, team lifting, staging within reach, good work height, pacing, rotation, keeping hands out of pinch points). The wall-stability/silica safety addresses the wall and the cutting — controlled by stability of the stone wall during construction (bracing/supporting where required) and silica control for cutting/dressing stone, plus caustic-mortar contact protection. And the scaffold access and falling material get access and falling-object controls. An AHA built on heavy-stone handling/ ergonomic control and wall-stability/silica safety, with access controls, addresses the hazards that define stone masonry.

From the field: what actually goes wrong

In fourteen years across federal, heavy civil, and industrial projects, stone masonry lays stone units in mortar to build solid stone walls, and it is the heaviest of the masonry trades, so its defining hazard is the weight and handling of the stone. The heavy-stone-handling and ergonomics hazard is the primary defining concern — stone units used in stone masonry are heavy, and often large and irregular in shape (especially rubble and ashlar stone), so lifting and placing them is a pronounced manual-handling and ergonomic hazard, often heavier and more awkward than block or brick — a major cause of back, shoulder, and musculoskeletal injuries, and a crush/pinch hazard when setting heavy irregular stone. So managing the heavy-stone handling and ergonomics (using mechanical handling and lifting aids for the heavy stone, team lifting, staging the stone within reach, keeping the work at a good height, pacing, rotating tasks, and keeping hands out of pinch points when setting the heavy irregular units) is the key control. The weight and irregularity of stone make handling the defining stone-masonry hazard.

The masonry-wall-stability/collapse and the stone-cutting-silica/mortar-contact are the other defining hazards. On the projects I have run, a stone masonry wall under construction — especially a heavy solid stone wall — must be stable, and a fresh or unbraced stone wall can be unstable and collapse, so stability of the stone wall during construction (braced/supported where required) is a control, and the scaffolds must be rated for the heavy stone loads. And the stone-cutting-silica hazard (cutting and dressing stone generates respirable silica, since many building stones are high in silica — wet cutting, dust extraction, respiratory protection) and the caustic-mortar contact (cement burns — gloves and skin protection) are the familiar masonry material hazards. The falling-object hazard is especially serious with heavy stone. The AHA built on heavy-stone handling/ergonomic control and wall-stability/silica safety is the one that protects the stone-masonry crew.

The bottom line

A Stone Masonry AHA names the heavy-stone-handling/ergonomics, the masonry-wall-stability/collapse, and the stone-cutting-silica/mortar-contact hazards with specific controls — managing the pronounced handling and ergonomics of heavy, irregular stone (mechanical/team lifting, pinch-point awareness), stability of the stone wall during construction, and silica control for cutting/dressing stone with caustic-mortar contact protection. The heavy-stone handling/ergonomic control and the wall-stability/silica safety are the defining concerns. The AHA that manages both is the one that protects the crew.

Frequently asked questions

Why is heavy-stone handling the defining stone-masonry hazard?

Stone units used in stone masonry are heavy, and often large and irregular in shape (especially rubble and ashlar stone), so lifting and placing them is a pronounced manual-handling and ergonomic hazard — often heavier and more awkward than block or brick, a major cause of back, shoulder, and musculoskeletal injuries, and a crush/pinch hazard when setting heavy irregular stone. Controls are managing the heavy-stone handling and ergonomics (mechanical handling/lifting aids, team lifting, staging within reach, good work height, pacing, rotation, keeping hands out of pinch points), and the handling/ergonomic controls.

What wall-stability hazards apply?

A stone masonry wall under construction — especially a heavy solid stone wall — must be stable, and a fresh or unbraced stone wall can be unstable and collapse. Controls are stability of the stone wall during construction (braced/supported where required, scaffolds rated for the heavy stone loads), and the wall-stability controls.

What silica and mortar hazards apply?

Cutting and dressing stone generates respirable silica (many building stones are high in silica), and the caustic mortar causes cement burns from skin contact. Controls are silica control for cutting/dressing stone (wet cutting, dust extraction, respiratory protection), preventing skin contact with the caustic mortar (gloves, skin protection), and the silica/contact controls.

What is stone masonry?

Stone masonry is the construction of walls and structures by laying stone units in mortar — building solid stone walls (ashlar, rubble, and coursed stone masonry) course by course. Because stone units are heavy and irregular (pronounced handling/ergonomics), a stone wall under construction can be unstable, and cutting stone generates silica with caustic mortar, those hazards apply.

Related AHAs and JHAs

• Stone Masonry Veneer AHA — the stone-veneer detail
• Stone Assemblies AHA — the stone-assembly fundamentals
• Stone Installation JHA — the stone-installation fundamentals
• Masonry and Block Wall Construction JHA — the masonry-construction fundamentals

Written by Mustafa Tok, CSP, ASP, CHST — OSHA Authorized Outreach Trainer with 14+ years of international construction safety experience across federal, heavy civil, and industrial projects.