# Death Foam (DD-043)

> When highly pathogenic avian influenza or virulent Newcastle disease hits a commercial flock, U.S. policy aims to kill the infected birds on the farm within 24 to 48 hours to stop the virus spreading. Water-based foam was developed for this after the 2004 Delmarva bird flu outbreak, and USDA and the AVMA gave it conditional approval in 2006. Firefighting-style foam is spread over floor-reared birds (broilers, turkeys, ducks) until it blocks their airways, causing physical hypoxia. In trials it killed broilers about as fast as CO2 or faster, with far fewer workers exposed to the virus. The AVMA has never classed it as euthanasia. In its 2026 depopulation guidelines, water-based foam is Tier 2, 'permitted in constrained circumstances', ranked below whole-house gassing and nitrogen-filled high-expansion foam.

- Department: Dark Facts (also Science)
- First published: 2025-03-02
- Last updated: 2025-03-02
- Permalink: https://detailenjoyer.com/case/death-foam/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## On the timeline

- **2004**: The Delmarva bird flu outbreak exposes problems with existing culling methods
- **2006**: USDA and the AVMA conditionally approve water-based foam for floor-reared poultry
- **2026**: The AVMA's depopulation guidelines rank water-based foam as Tier 2, below whole-house gassing

Full timeline: https://detailenjoyer.com/timeline/?case=death-foam

## Quick facts

- **DD-043-F01**: Water-based foam culls poultry by blocking their airways. It was conditionally approved in the U.S. in 2006 after the 2004 Delmarva bird flu outbreak. _(Write-up · Exhibit E (Conditional approval))_
- **DD-043-F02**: The AVMA's 2026 depopulation guidelines rank water-based foam below whole-house gassing, as a method permitted only in constrained circumstances. _(Write-up · Exhibit F (Where it ranks now))_

## Write-up

Firefighting foam is used to cull poultry in bird flu outbreaks. Vets rank it below whole-house gassing, for use only in constrained circumstances.

1. **Why whole flocks are killed**: In an HPAI outbreak, U.S. policy aims to 'stamp out' the virus by depopulating infected premises within 24 to 48 hours, before more virus is produced.
2. **Born of an outbreak**: Researchers developed the foam method after the 2004 Delmarva avian influenza outbreak exposed problems with existing methods: too few trained workers, fatigue, and responders' exposure to the virus.
3. **How it works**: A blanket of foam spread over the birds rapidly blocks their airways. That causes physical hypoxia, whereas CO2 causes chemical hypoxia.
4. **Time to death**: In small-group trials with broilers, foam stopped activity in about 64 to 73 seconds, compared with 139 seconds under a CO2 tent. Later EEG studies found similar times to unconsciousness for broilers, layers and turkeys, but CO2 was faster for ducks.
5. **Conditional approval**: USDA and the AVMA conditionally approved water-based foam for floor-reared poultry in 2006. The AVMA's welfare committee said it couldn't reconcile foam with its definition of euthanasia.
6. **Where it ranks now**: The AVMA's 2026 guidelines list water-based (medium/low-density) foam as Tier 2, permitted in constrained circumstances. Tier 1 (preferred) includes whole-house CO2 or N2 gassing and high-expansion nitrogen-filled foam.

## Related case files

- [CryoBranding (DD-006)](https://detailenjoyer.com/case/cryobranding/): Another farm-animal practice up close.
- [Dead Pools (DD-049)](https://detailenjoyer.com/case/dead-pools/): Another way animals die from lack of oxygen.

## Reel vs. record

- **Overstated**: 'poultry and livestock.' Water-based foam is approved and studied for floor-reared poultry (broilers, layers, turkeys, ducks), not livestock in general. The birds in the footage appear to be turkeys. [Avian Diseases 2012; USAHA 2006; frames]
- **Muddled**: 'high expansion firefighting foam.' U.S. guidance separates water-based medium/low-density foam (Tier 2) from high-expansion nitrogen-filled foam (Tier 1, preferred). [USDA APHIS; AVMA 2026]
- **Misleading comparison**: 'considered … less labor intensive than … gassing.' It does use fewer workers, but the AVMA ranks whole-house gassing above water-based foam. Foam is permitted only in constrained circumstances and has never been classed as euthanasia. [USDA APHIS; USAHA 2006; Benson 2007]
- **Confirmed**: foam kills by blocking the airway. Trials found times to death comparable to or faster than a CO2 tent for chickens, but CO2 was faster for ducks. 'Cost effective' wasn't checked against any source. [Benson 2007; Avian Diseases 2012]

## Video: Death Foam: Firefighting Foam Is Used to Cull Poultry in Bird Flu Outbreaks

- Duration: 22.1 s · Published: 2025-03-02
- File: https://detailenjoyer.com/assets/videos/DGuLwoexhU_.mp4

### Transcript

DID YOU KNOW? Foam depopulation is a method used in mass culling of poultry and livestock, primarily during disease outbreaks like avian influenza. It involves flooding an enclosed area with high expansion firefighting foam, which suffocates animals by blocking their airways, leading to rapid asphyxiation. The method is considered efficient, cost effective, and less labor intensive than traditional culling techniques like gassing or manual euthanasia. NOW YOU KNOW!

## Questions & answers

**Q: How does water-based foam kill poultry?**  
A: It's physical hypoxia; CO2 causes chemical hypoxia. _(Source: Write-up · Exhibit C (How it works) · Benson et al., Foam-Based Mass Emergency Depopulation of Floor-Reared Meat-Type Poultry Operations (Poultry Science, 2007); Report of the USAHA Committee on Transmissible Diseases of Poultry (2006))_

**Q: Which outbreak prompted development of the U.S. foam method?**  
A: The response to the 2004 event exposed the limits of existing methods. _(Source: Write-up · Exhibit B (Born of an outbreak) · Benson et al., Foam-Based Mass Emergency Depopulation of Floor-Reared Meat-Type Poultry Operations (Poultry Science, 2007))_

**Q: When did USDA and the AVMA conditionally approve water-based foam?**  
A: It was approved for floor-reared poultry. _(Source: Write-up · Exhibit E (Conditional approval) · USAHA Resolution 44: Water-Based Foam for Mass Depopulation of Poultry (2006); Mass Emergency Water-Based Foam Depopulation of Poultry (Avian Diseases, 2012; PubMed))_

**Q: Where does water-based foam rank in the AVMA's 2026 guidelines?**  
A: Whole-house gassing and nitrogen foam are Tier 1. _(Source: Write-up · Exhibit F (Where it ranks now) · HPAI Response Goals & Depopulation Policy (USDA APHIS); AVMA Guidelines for the Depopulation of Animals: 2026 Edition (American Veterinary Medical Association))_

**Q: For which birds was CO2 faster than foam in EEG studies?**  
A: Pekin ducks lost consciousness sooner with CO2. _(Source: Write-up · Exhibit D (Time to death) · Benson et al., Foam-Based Mass Emergency Depopulation of Floor-Reared Meat-Type Poultry Operations (Poultry Science, 2007); Mass Emergency Water-Based Foam Depopulation of Poultry (Avian Diseases, 2012; PubMed))_

## Sources

- [AVMA Guidelines for the Depopulation of Animals: 2026 Edition (American Veterinary Medical Association)](https://www.avma.org/sites/default/files/2026-06/Depopulation_Guidelines_2026.pdf)
- [HPAI Response Goals & Depopulation Policy (USDA APHIS)](https://www.aphis.usda.gov/sites/default/files/depopulationpolicy.pdf)
- [Benson et al., Foam-Based Mass Emergency Depopulation of Floor-Reared Meat-Type Poultry Operations (Poultry Science, 2007)](https://doi.org/10.1093/ps/86.2.219)
- [Mass Emergency Water-Based Foam Depopulation of Poultry (Avian Diseases, 2012; PubMed)](https://pubmed.ncbi.nlm.nih.gov/23402109/)
- [USAHA Resolution 44: Water-Based Foam for Mass Depopulation of Poultry (2006)](https://usaha.org/upload/Committee/TransDisPoultry/resolution44-2006.pdf)
- [Report of the USAHA Committee on Transmissible Diseases of Poultry (2006)](https://usaha.org/upload/Committee/TransDisPoultry/report-pad-2006.pdf)

## Cite this case file

Easterling, Marcus. "Death Foam." The Detail Department (DetailEnjoyer), case file DD-043, last updated Mar 2, 2025. https://detailenjoyer.com/case/death-foam/