Guidelines

How sensitive is alternative light source?

How sensitive is alternative light source?

Sensitivity of ALS on days 1, 7, and 14 was 76.8%, 69.6%, and 60.7%, respectively, compared to 69.6%, 60.0%, and 32.1% for white light. The specificity of ALS on days 1, 7, and 14 was 51.6%, 59.7%, and 53.2%, respectively, compared to 71.0%, 81.4%, and 86.9% for white light.

What is an alternative light source?

Abstract. Alternative light sources (ALSs) are commonly used at crime scenes and in forensic laboratories to collect evidence such as latent fingerprints, body fluids, hair, and fibers.

How much does alternative light source cost?

The MicroBlue has been the standard “poor man’s” Forensic Light Source for nearly 15 years. (For less than $40, you couldn’t go wrong.)

What is the most popular alternate light source?

Fluorescent Powders are used widely as the primary method of fingerprint treatment at crime scenes when using a Forensic or Alternate Light Source. They are available in various colors. Red, Green, Orange, Pink, Yellow, Gold, Blue, are the most common.

Is blood visible under UV light?

You see, blood does not fluoresce by applying UV or visible blue light. Although blood does not fluoresce, certain other physiological fluids will. UV alternate light sources can reveal the following: seminal fluid, saliva and urine stains. Also, certain narcotics will fluoresce as will bone and teeth fragments.

What types of evidence can be better visualized using alternate light sources?

UV alternate light sources can reveal the following: seminal fluid, saliva and urine stains. Also, certain narcotics will fluoresce as will bone and teeth fragments. Other uses of alternate light sources Indeed, many forms of physical evidence will fluoresce.

What is an alternate light source forensics?

An alternate light source (ALS) is commonly used in the forensic setting to visualize evidence that may be difficult to detect with the naked eye. Dependent on the wavelength of light selected fluorescence, phosphorescence, absorption and reflection may all occur when evidence is illuminated with a light source.

What glows pink under blacklight?

Flying squirrels secretly glow pink thanks to fluorescence. A male three month old northern flying squirrel (Glaucomys sabrinus). This species and its two American cousins glow pink under UV light.

Does sperm show up under black light after washing?

While semen will fluoresce, so do many other bodily fluids. Substances such as sweat, urine, and saliva will all glow under UV light. So while using a black light can be helpful in discovering bodily fluids that are not visible to the naked eye, it’s not definitive proof a stain is semen.

What do you call an alternate light source?

Alternate light source (ALS): a tool used to help visualize evidence that is not apparent to the naked eye. ALS typically utilize the UV and visible light spectrum. Also known as a forensic light source (FLS). Alternating current (AC) power: a type of power supply where the electric current cyclically changes direction.

What is an alternate Light Source ( ALS )?

Alternate light source (ALS):a tool used to help visualize evidence that is not apparent to the naked eye. ALS typically utilize the UV and visible light spectrum. Also known as a forensic light source (FLS).

How are alternate light sources used at crime scenes?

The use of alternate light sources provides a highly practical and efficient means of locating physical evidence at crime scenes. The invention and perfection of Light Emitting Diodes (LEDs) has further advanced evidence recovery since even 1 and 3 watt LEDs can be installed in small, hand-held flashlights, and their performance is remarkable.

What kind of light source does Foster and Freeman use?

In addition to handheld Crime-lites, Foster+Freeman manufactures two models multi-wavelength laboratory light source. While the Crime-lite 8×4 is ideal for the visualization and enhancement of fingerprints, the Crime-lite ML2 has applications including the detection of body fluids and ‘marking-up’ of evidence.