Collection Care:Environmental Factors

Part III: Fungi, Pests, and Air Pollution

Valinda S. Carroll

Biological Agents

FungiInsectsRodents

Fungi

Mold spores are present on most objects. High humidity activates mold growth.

Schedule regular inspections of storage areas to ensure that fungal growth is detected early.

Mold Safety Always wear personal protective

equipment: N95 respirator, gloves, goggles

Use a HEPA vacuum and a soft brush ( a HEPA or ULPA filter prevents the vacuum cleaner from filling the air with microscopic mold spores)

Create a work area separate from collections storage to avoid cross-contamination

Insects

Many insects are attracted to food eaten by humans

Insects seek shelter in human habitations, especially during inclement weather

Many insects feed on starches and proteins in museum artifacts

Some insects eat only one type of material, so it is useful to consult an identification chart

Rodents

Rodents are attracted to food eaten by humans

Rodents seek shelter in human habitations, especially during inclement weather

Rodents feed on starches and proteins in museum artifacts

Pest Control Methods

Seal entry points (caulk, weather-strip, etc.)

Remove food sources and breeding places

Use outdoor bait stations to control rodents before they enter the building

Monitor insect activity with sticky traps and pheromone lures

Pest Control Methods

Lower temperatures, possibly to freezing point

Reduce relative humidity Remove sources of oxygen

(nitrogen or argon chamber, Ageless™ oxygen absorber)

Chemical MethodsChemical pesticides and fungicides can damage historic artifacts. Be aware that “natural” or “organic” pesticides may be safer for human health, but they are not designed for the preservation of historic artifacts.

Museums are encouraged to avoid using chemicals, except as a last resort. Then consult with a conservator regarding the safety of any chemical for use around collections of value.

Air Pollutants

Soot and smoke Outdoor pollutants Volatile organic compounds Off-gassing from collections and exhibit

materials Ozone

Open Flames

Use electric or battery-operated candles and fireplace inserts to avoid unnecessary risks to your collection

•Candles generate soot

•Flames generate very high heat

•Genuine candles, working fireplaces, and cigarette smoking may lead to fires

Outdoor Pollutants

Car exhaustFactoriesForest fires

Outdoor Pollutants

Keep windows and doors closed

Change filters in HVAC system

Store artifacts in protective enclosures

Volatile Organic Compounds

Regular Paint Low VOC Paint

Volatile Organic Compounds

Low VOC PaintVolatile Organic Compounds (VOC) are emitted by paint, carpet, cleaning products, and other materials. Interior-grade plywood emits chemicals such as formaldehyde and acetic acid, known to damage artwork and historic artifacts.

As a result of health and environmental concerns, many product labels list quantities of VOC. To protect collections, avoid exposing them to such compounds.

This paint has 0g/L of VOC

Off-gassing

Protect artifacts from contact with materials known to release harmful gasses

Unstable plastics (cellulose acetate, cellulose nitrate, etc.)

Unsealed wood (interior grade plywood, oak, etc.)

Paints or cleaning materials of unknown or untested composition

Volatile acetic acid

(cellulose acetate film deterioration)

Controls

slight

severe

severe

moderate

Monitor off-gassing with A-D strips. These strips are designed to monitor the pH level of air in a closed container. Acid turns the strips green.

The Oddy test provides a simple assessment of exhibit materials. Polished copper coupons, shown below, are employed in the test. The far right sample shows slight tarnish as compared with the other two copper coupons.

Silver, lead, and copper coupons may corrode under slightly different conditions, so each metal is compared to a control in the Oddy Test. The test normally relies on visual examination, which may be unreliable.

Oddy Test

Hidden dangers

Ozone

Photocopiers and laser printers emit ozone. Keep such machines in office spaces separate from from collections storage areas.

Protective Housing Materials

Absorb or adsorb chemical pollutants from the air

Thin sheets can be incorporated into frames and exhibit cases

May act as mechanical barriers to pollutants

Easy to usePlastic films and bags with Intercept ™ technology (finely divided copper)

Protective Housing Materials

Microchamber ™ paper Bainbridge Alpharag

Artcare ™ Scavengel ™ cloth Activated charcoal

cloth Corrosion Intercept ™

films and bags (plastic impregnated with finely divided copper)

Protective Housing Materials

Activated charcoal and potassium permanganate

sheets

Zeolite-containing alkaline rag board

Protective Housing Materials

Capacity to counteract pollutants not easily determined

Shelf life not easily determined

More expensive than traditional housing materials

Agents of Deterioration

High Temperature Humidity Light Pests and Fungi Handling Air Pollution

This is the end of Part III: Pests, Fungi, and Air Pollution.