Selective Site Demolition AHA (Activity Hazard Analysis / Job Hazard Analysis)
Updated 2026-06-23
A Selective Site Demolition AHA (Activity Hazard Analysis / Job Hazard Analysis) is the plan that keeps the crew performing selective site demolition safe from the utility and existing-condition hazards, from structural instability during selective removal, and from the equipment and debris. Selective site demolition removes specific site features while preserving others — combining the utility and existing-condition hazard, the structural-stability-during-selective-removal hazard, and the equipment and debris hazard. This guide walks through building a Selective Site Demolition AHA that names the utility/existing-condition, structural-stability, and equipment/debris hazards and assigns the utility, stability, and equipment controls that hold up in the field.
Why selective site demolition needs its own AHA
Selective site demolition is the removal of specific site features, structures, pavements, or elements while preserving adjacent features that are to remain — the selective removal of site improvements (walls, slabs, pavements, foundations, site structures) as part of renovation or redevelopment, where the challenge is removing what must go without damaging what stays. The defining features are the existing conditions and utilities (often unknown or active in an existing site), the structural stability of what is being selectively removed and what remains, and the demolition equipment and debris. The hazards combine the utility and existing-condition (site demolition is done in an existing site with utilities and existing conditions — active/unknown utilities (strike hazard), hazardous materials, and unknown existing conditions), the structural-stability-during-selective-removal (selectively removing part of the site/structures while preserving others — the stability of what is being removed and what remains (unplanned collapse, undermining adjacent features)), the equipment and debris (the demolition equipment (excavators, breakers) and the debris — the struck-by, equipment, and debris hazards), and the dust/noise. The utility/existing-condition and the structural-stability justify a dedicated AHA.
Breaking selective site demolition into steps
The steps for a Selective Site Demolition AHA follow the demolition:
- Survey the site and locate utilities/existing conditions
- Plan the selective removal (protect what remains)
- Disconnect/isolate the utilities to be removed
- Selectively remove the features (controlled)
- Protect the adjacent features that remain
- Manage the utility, stability, and equipment hazards
- Manage the debris
- Complete
Each step carries a hazard, and the utility/existing-condition, the structural-stability, and the equipment/ debris are where the most significant risks concentrate.
The hazards step by step
Utility and existing-condition
Site demolition is done in an existing site with utilities and existing conditions — active/unknown utilities (strike hazard), hazardous materials, and unknown existing conditions. The controls are locating and identifying utilities before demolition (active utilities must be found and isolated — striking an active utility during demolition is serious), disconnecting/isolating utilities before removing what they serve, a pre-demolition survey (utilities, hazardous materials, existing conditions), and the utility/existing-condition controls. The utility/existing-condition is a defining hazard — existing sites have active/unknown utilities and conditions. (These follow the demolition-survey fundamentals.)
Structural-stability-during-selective-removal
Selectively removing part of the site/structures while preserving others — the stability of what is being removed and what remains (unplanned collapse, undermining adjacent features). The controls are an engineered demolition plan/sequence for selective removal (removing elements in an order that maintains stability), protecting and not undermining the adjacent features that remain (supporting/shoring where removal affects what stays), controlled removal (not creating unplanned collapse), and the stability controls. The structural- stability is a defining hazard — selective removal must maintain the stability of what remains. (These follow the demolition-stability fundamentals.)
Equipment and debris
The demolition equipment (excavators, breakers) and the debris — the struck-by, equipment, and debris hazards. The controls are mobile-equipment safety (separation, exclusion zones around demolition equipment), managing the debris (controlled generation, safe handling/removal), struck-by protection, and the equipment/debris controls. The equipment/debris is a defining hazard. (These follow the demolition-equipment fundamentals.)
Dust/noise
The dust and noise (demolition dust, including silica; noise) carries the dust/noise hazard. The controls are dust control (water/wet methods for silica), hearing protection, and the dust/noise controls. (These follow the silica and noise fundamentals.)
A simple Selective Site Demolition AHA structure
| Step | Hazard | Control | Standard |
|---|---|---|---|
| Survey | Utilities / conditions | Survey site, locate utilities/existing conditions | OSHA 1926.850 |
| Plan | Instability | Plan selective removal, protect what remains | OSHA 1926.850 |
| Isolate utilities | Utility strike | Disconnect/isolate utilities before removal | OSHA 1926.850 |
| Remove | Collapse | Selective removal per engineered sequence | project |
| Protect adjacent | Undermining | Protect/shore adjacent features that remain | project |
| Manage debris | Struck-by / dust | Manage debris, dust control, exclusion zones | OSHA 1926.1153 |
Utility/existing-condition survey and selective-removal stability
A Selective Site Demolition AHA centers on the utility/existing-condition survey and selective-removal stability. The utility/existing-condition survey addresses the existing site's utilities and conditions — controlled by locating and identifying utilities before demolition, disconnecting/isolating utilities before removing what they serve, and a pre-demolition survey (utilities, hazardous materials, existing conditions). The selective-removal stability addresses removing part while preserving the rest — controlled by an engineered demolition plan/ sequence, protecting and not undermining the adjacent features that remain (supporting/shoring where needed), and controlled removal that does not create unplanned collapse. And the equipment and debris get mobile-equipment and debris controls. An AHA built on the utility/existing-condition survey and selective-removal stability, with equipment controls, addresses the hazards that define selective site demolition.
From the field: what actually goes wrong
In fourteen years across federal, heavy civil, and industrial projects, selective site demolition removes specific site features while preserving what stays, and its defining hazards come from working in an existing site (with its utilities and unknown conditions) and from the selectivity itself (removing part without destabilizing the rest). The utility and existing-condition hazard is a primary defining concern — site demolition is done in an existing, previously-built site, which means there are utilities (often active, and sometimes not accurately documented) and existing conditions (hazardous materials, unknown construction) that the demolition can encounter. Striking an active utility during demolition is serious (an active electrical, gas, water, or sewer line hit by a breaker or excavator), so locating and identifying the utilities before demolition, disconnecting and isolating the utilities before removing what they serve, and a thorough pre-demolition survey (utilities, hazardous materials, and existing conditions — which is where the assessment work from the previous batch feeds in) are the controls. The existing site is full of things the demolition can hit, so finding them first is the control.
The structural-stability-during-selective-removal and the equipment/debris are the other defining hazards. On the projects I have run, the defining challenge of selective demolition is exactly the selectivity: you are removing part of the site or structures while preserving adjacent features that must remain, so the stability of both what is being removed and what remains is the concern — removing an element can cause unplanned collapse of what is being demolished, or can undermine or destabilize the adjacent features that are supposed to stay. So an engineered demolition plan and sequence for the selective removal (removing elements in an order that maintains stability), protecting and not undermining the adjacent features that remain (supporting or shoring where the removal affects what stays), and controlled removal are the controls. Selective demolition is harder than total demolition precisely because you have to protect what stays. The equipment and debris hazard (mobile-equipment safety with exclusion zones around the demolition equipment, and managing the debris) and the dust and noise (including silica dust from breaking concrete) round it out. The AHA built on the utility/existing-condition survey and selective-removal stability is the one that protects the selective-demolition crew.
The bottom line
A Selective Site Demolition AHA names the utility/existing-condition, the structural-stability, and the equipment/debris hazards with specific controls — locating and isolating utilities with a pre-demolition survey of the existing site, an engineered selective-removal sequence that protects and does not undermine what remains, and mobile-equipment safety with dust control. The utility/existing-condition survey and the selective-removal stability are the defining concerns. The AHA that manages both is the one that protects the crew.
Frequently asked questions
Why are utilities and existing conditions a primary hazard?
Site demolition is done in an existing, previously-built site with utilities (often active, sometimes not accurately documented) and existing conditions (hazardous materials, unknown construction) that the demolition can encounter — and striking an active utility during demolition is serious (an active electrical, gas, water, or sewer line hit by a breaker or excavator). Controls are locating and identifying utilities before demolition, disconnecting/isolating utilities before removing what they serve, a pre-demolition survey (utilities, hazardous materials, existing conditions), and the utility/existing-condition controls.
Why is stability the defining challenge of selective removal?
The defining challenge of selective demolition is the selectivity — removing part of the site or structures while preserving adjacent features that must remain — so removing an element can cause unplanned collapse of what is being demolished or undermine the adjacent features that are supposed to stay, making it harder than total demolition. Controls are an engineered demolition plan/sequence for selective removal (removing elements in an order that maintains stability), protecting and not undermining the adjacent features that remain (supporting/shoring where removal affects what stays), controlled removal, and the stability controls.
What equipment and debris hazards apply?
The demolition equipment (excavators, breakers) and the debris bring the struck-by, equipment, and debris hazards. Controls are mobile-equipment safety (separation, exclusion zones around demolition equipment), managing the debris (controlled generation, safe handling/removal), struck-by protection, dust control (water/wet methods for silica), hearing protection, and the equipment/debris controls.
What is selective site demolition?
Selective site demolition is the removal of specific site features, structures, pavements, or elements while preserving adjacent features that are to remain — the selective removal of site improvements as part of renovation or redevelopment. Because it is done in an existing site (utilities/conditions), requires maintaining the stability of what remains, and uses demolition equipment, those hazards apply.
Related AHAs and JHAs
- Paving Removal AHA — a specific selective removal (pavements)
- Structure Demolition AHA — the demolition of structures
- Hazardous Material Assessment AHA — the pre-demolition hazmat survey
- Demolition Work JHA — the demolition 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.