ZOO MED
REPTISUNMEGACOMPACT UVBLAMP TESTS
An investigation into the 65W, 110V
Mega Compact Fluorescent Lamp fromZoo MedThomas Griffiths, 2022
tom@tomaskas.co.uk
V 4.12.22

TABLE OF
CONTENTS
Disclaimer .................................................................................. 1

REASONS FOR TEST .................................................... 2
TERMINOLOGY USED .................................................. 3
Kit ............................................................................................. 3
Lamp/Bulb .................................................................................. 3
CFL/Compact Fluorescent ............................................................. 4
UVI............................................................................................ 4
UVB ........................................................................................... 4
Ferguson Zone(s) ........................................................................ 5
Colour Temperature (and Corrected Colour Temperature)................. 5
Colour Rendering (Index)/CRI ....................................................... 6

TESTING METHODS..................................................... 7
Equipment .................................................................................. 7
Methods .................................................................................... 10

PRODUCTS TESTED ................................................... 11
65W ReptiSun Mega Compact UVB Lamp ....................................... 11

INITIAL OBSERVATIONS .......................................... 12
Description and Build Quality ....................................................... 12
Box/Packaging ........................................................................... 13
Accessories ................................................................................ 14
Presumptions and General Observations ........................................ 14
Photographs .............................................................................. 15

UV PERFORMANCE .................................................... 18
Burn-in and Degredation ............................................................. 19
Centre Point After Burn-in ........................................................... 21

IRRADIANCE CHARTS ............................................... 23
Purpose..................................................................................... 23
Disclaimer ................................................................................. 23
Lamp 3 – No Reflector ................................................................ 24
Lamp 3 – With Deep Dome Fixture ............................................... 25
Lamp 3 – With combo Deep Dome Fixture ..................................... 26

SPECTRAL MEASUREMENTS ...................................... 27
280 – 400nm ............................................................................. 27
250 – 350nm ............................................................................. 29

260 – 800nm ............................................................................. 31

COLOUR MEASUREMENTS ......................................... 33
Overview ................................................................................... 33
Colour Values ............................................................................ 34

OTHER MEASUREMENTS ........................................... 38
Overview ................................................................................... 38
Measurments (AFter Burn-in) ....................................................... 39
Light Spread .............................................................................. 39
Thermal Imaging (AFter Burn-in) ................................................. 40

COMMENTARY ON FINDINGS .................................... 41
Overall ...................................................................................... 41
UVI and UVB .............................................................................. 41
Spectrum and Vitamin D3 synthesis .............................................. 43
Colour Rendering and vision ........................................................ 45
Other Comments ........................................................................ 45

FURTHER TESTS........................................................ 47
Longevity and Degridation ........................................................... 47
Teardown .................................................................................. 47

SPECIAL THANKS ..................................................... 48

Colleagues ................................................................................. 48
Copy ......................................................................................... 48

LITERATURE AND FURTHER READING ...................... 49
Peer-Reviewed Literature ............................................................ 49
Other Literature ......................................................................... 52

DISCLAIMER
The content in this document including, but not limited to, the text,
graphics, images, links, and other materials is for informational
purposes only. The content is not intended to be a substitute forprofessional veterinary advice, diagnosis, or treatment, and does notconstitute as medical or other professional advice. Tomaskas Ltd. does
not recommend or endorse any specific tests, physicians, products,
procedures, opinions, or other information that may be mentioned inthis document, or on other company websites. Reliance on any
information provided herein is solely at your own risk. The information
provided in this document is designed to support, not replace, therelationship that exists between yourself and a veterinary surgeon.
Never disregard professional medical advice or delay in seeking it
because of something you have read in this document.
The details provided in this document are based on sole use, and the
document contains both scientific information as well as personal
opinion. Other people may have different results. The tests have been
performed to our best knowledge. Although, the tests do notsubstitute that of a laboratory test. There are uncontrollable variables
when testing a single batch of any item. Different items of the samemodel number may differ due to their manufacturing batch oroperating conditions.
This document may refer to the overall exotic animal keeping hobby as
the “reptile hobby”, but this is a force of habit – Tomaskas Ltd. does infact mean the keeping of the broader herpetological spectrum,including invertebrates, amphibians, and even birds.

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REASONS
FOR TEST

These tests were completed independently on behalf of Zoo Med
Laboratories (Zoo Med). Zoo Med paid for a full version of this reportand supplied multiple lamps for testing.
Zoo Med is a brand based in the USA, with products sold worldwide.
They produce and sell products for the reptile and fishkeeping
communities.
In order to provide the hobby with a base understanding of suchproducts, it’s important that impartial tests are conducted. We have a
duty, as a community, to look out for each other and shareappropriate good practice.
These tests aim to discover if products are suitable for the hobby,
independent of the manufacturer’s claims.
These tests aim to provide a better understanding of the product inquestion. The product is aimed at primarily providing a UVB provision.
This is the public version of the report.

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TERMINOLOGYUSEDAs with many things, there may be more than one correct or colloquial
way to describe the same item. There may also be common terms
used that may not be correct in everyday usage. I’ve tried to remain
consistent throughout the document so that if I refer to a specific partof an item, you as the reader will know with confidence which part I’mreferring to. I’m only human though, and there may be mistakes.

KIT
This refers to everything that comes in a box, including fittings andinstructions.

LAMP/BULBThis refers to the main item in the kit. It is a fluorescent lamp with aspiral shape, tapering towards the lowest point. Inside the actual bulb

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are electronics to ensure that the lamp turns on and works asintended.

CFL/COMPACT FLUORESCENT
The term given to a lamp that uses fluorescent phosphor technology,
and is considered “compact” in the sense that it generally has a small
form factor.

UVIThis is shorthand for Ultra Violet Index. UVI is a standardised
measurement for the appropriate wavelengths of radiation associatedwith essential biological processes involving the synthesis of Vitamin
D3 – it is often used as a measure of solar UV radiation at the Earth’s
surface in terms of potential damage to the skin and the eye. The
higher the UVI, less time it takes for harm to occur. This document
does not aim to educate about this biological process specifically, andfurther reading is readily available online. By continuing, it ispresumed that you have an understanding of UVI and its relevance tothese tests. UVI is not to be confused with UVB. UVI is not to be
confused with the Ferguson Zones.

UVB
UVB is the term for part of the electromagnetic spectrum on certain
wavelengths, generally between 280 and 320nm. This document does
not aim to educate about this specifically, and further reading isreadily available online. By continuing, it is presumed that you have an
understanding of UVB – including the differences between terrestrial(solar) UVB, which is around 295-320nm, and the more dangerous

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non-terrestrial (non-solar) UVB, which is from 280nm to around
295nm.

FERGUSON ZONE(S)The Ferguson Zones are classification markers for different exposurelevels to different UVI. There are 4 Zones. Animals that expose
themselves naturally to lower UVI are classified as Ferguson Zone 1,
and animals that naturally expose themselves to high UVI areclassified as Ferguson Zone 4. This document does not aim to educate
about this specifically, and further reading is readily available online.
By continuing, it is presumed that you have an understanding of
Ferguson Zones – including the differences between the different
Zones.

COLOUR TEMPERATURE (AND CORRECTED COLOURTEMPERATURE)
Colour temperature, or CT, is widely used to define the colour
appearance of a light source. Colour temperature is technically onlyused for “true” light sources – defined as a black body that reads closeenough to the Planckian locus.
Corrected Colour Temperature, or CCT, is used on a light source that
doesn’t read close to the Planckian locus.
Both are defined in degrees Kelvin where a Warm White is around2700K moving to Neutral White at around 4000K to Cool White, 5000K
or more. Note that Colour Temperature and CCT do not tell you
anything about the colour rendering ability of a light.
This document does not aim to educate about this specifically, andfurther reading is readily available online. By continuing, it is5

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presumed that you have an understanding of CT/CCT – including thedifferences and similarities.

COLOUR RENDERING (INDEX)/CRI
Broadly defined as an indication of how well a light source can provide
wavelengths that allow for certain colours to be visible to the humaneye. This is defined by the CIE in greater detail, along withstandardisations on measuring the level of colour rendering capability– referred to as the “index” of colour rendering.
Light with a low CRI is less effective as one with a high CRI. The CRI of
unobstructed sunlight is 100.
This document does not aim to educate about this specifically, andfurther reading is readily available online. By continuing, it ispresumed that you have an understanding of CRI.

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TESTING
METHODSEQUIPMENT
In order to ensure that results are as true and comparable as possible,
I have used standardised measuring devices for the tests. I have useda SolarMeter 6.5 for measuring UVI, and a SolarMeter 6.2 formeasuring UV in µW/cm².
The spectral response of these broadband meters is shown below.

To allow for full spectrometry, a calibrated FLAME Spectrometer from
Ocean Optics was used alongside their flagship software – OceanView.

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Room temperature measurements were taken with an Inkbird branded
digital thermometer, with part number IBS-TH2. The manufacturer
claims the device to have an accuracy of ±0.3°C.
A drywipe backboard was used for the “manual” portions of the tests.
The backboard was pre-marked with a grid pattern. The grid used is
2.5cm squares. The board is approx. 2mx2m in total.
The distance from the unit was determined using a Stanley tapemeasure, with points marked on the backboard.
A Windows 10 PC with Microsoft Office and Adobe Photoshop CC 2015
was used to digitise the results and write up this report.
A power meter was used, model KWE-PM01, to monitor power usage.
A Dr Meter LX1330B was used to manually determine LUX values.
The lamps are 110V. I used a voltage transformer to correctly power
the lamps.
SCHOTT N-WG295 Long Pass Glass (WG295 Glass) was used whereappropriate to monitor for UVC vs noise on the spectrometer.

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For some of the irradiance measurements, I paired the lamp with
common Zoo Med products that are recommended on packaging foruse with this lamp. I utilised the Zoo Med Deep Dome Lamp Fixture
and the Zoo Med Combo Deep Dome Dual Lamp Fixture, both pictured
below.

When utilising the Combo Deep Dome Dual Lamp Fixture, a 150W Zoo
Med Repti-Basking lamp was also placed in situ, to replicate how it
would be utilised in every day use. Below is an image showing how the
CFL sits in relation to the heat lamp.

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METHODS
Precaution was taken with all tests, as there should be when dealing
with UVB-emitting devices. “Factor 50” UV protection sun cream wasused on skin, with care taken not to spread any onto the equipment orlamps.
The method for creating ISO Irradiance charts is very close to themethod documented by UV Guide. I have made comparisons with myresults and those of the UV Guide, and the results are withintolerances – this means that the results are comparable to those of the
UV Guide.
Info here: (http://www.uvguide.co.uk/makingspreadcharts.htm)
Before every test took place, a dry microfibre towel was used to wipe
the lamp to ensure that the lamp was clean.
UVI was measured in the testing room before each test to ensure that
results were only measuring the lamps and not any other sources.
Spectrometer readings were taken in line with standard processes.
The Reptile Lamp Database was utilised for some technical analysis.
The lamps were given 30 – 60 minutes to “warm up” before eachindividual test, unless otherwise noted.
The lamps had between 100 – 150 hours of “burn-in” before the tests
began, unless otherwise noted.

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PRODUCTSTESTEDThe following product was tested.

65W REPTISUN MEGA COMPACT UVB LAMP
Multiple lamps were tested for Zoo Med. Each lamp was assigned anumber. This public report is showing just one of the lamps, for thesake of easier analysis. Each lamp produced very similar results.
To ensure this report was both fair and accessible, I wanted to select arandom lamp to show the results of. This way the lamp shown was not
the “best” or “preferred” lamp. The lamp selected was not influenced
by data or by Zoo Med. I decided to input the total number of lamps
tested into www.random.org to select a random lamp to for the public
report. The generator selected “Lamp 3”.

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INITIAL
OBSERVATIONSDESCRIPTION AND BUILD QUALITY
The lamps are – as expected for any glass lamp – delicate.
The lamps are an E26 fitting.
The lamps are 120mm in diameter at their widest point.
The ballast portion of the lamps, typical for CFLs, are approximately
80mm wide and 79mm tall. The ballast is made from white plastic.
The lamps are branded with the Zoo Med logo.
The lamps show markings for their wattage and voltage.
There are safety markings on the lamps for Mercury (Hg), and aconvenient spot to write the date of installation so that a user cankeep track of the 12-month lifespan. There are no CE or UKCA
markings.
There is a grammatical error on the lamps, with a missing space where
it says “radiationfor” instead of “radiation for”.

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BOX/PACKAGING
The box looks and feels high quality in general, there is no blurry
printing or any off colours. The product’s name is clearly visible on
every main face of the box.
The box has brown/bronze accents with black areas, and the design ismaintained throughout.
The lamp is made in China, according to the box. The box does notcontain a Hg mark but warns that the product contains Mercury andthe possible side effects of exposure. The box is very clear about thedangers of misuse of the lamp and where a user can find further
information before purchasing.
The front of the box has a high-quality image of a tortoise, it appears
to be a Redfoot Tortoise (Chelonoidis carbonarius). The sides of thebox contain further images of some kind of agamid lizard (presumably
a Frilled Dragon, Chlamydosaurus kingii) and a Monitor Lizard(possibly a juvenile Nile Monitor, but certainly of family Varanidae).
The box lists that the lamp is useful for larger animals, or groups ofsmaller animals.
There are different configurations provided, with different dome
products being recommended, and different distances being
recommended for different species.
The box boasts that the lamp has a 12-month lifespan. This is common
for T5HO lamps, but not often advertised in CFLs.
The lamp is packaged inside a polystyrene protector – making it very
well protected in transit.
There is a double-sided sheet of instructions included in the box.
The instructions provide some clear advice on how best to use thelamp, as well as showing some basic details on the use of the lamp
above a mesh screen.

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ACCESSORIESNo accessories are included.

PRESUMPTIONS AND GENERAL OBSERVATIONS
The lamp is much larger than a standard CFL. It has a peculiar “conelike” shape which is unique in the main hobby. I have seen some “noname” brands use a similar design – such products are available fromvarious sellers on Amazon. Those lamps are not tested here.

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PHOTOGRAPHS
Here are some images of the lamp, and box etc. Descriptions areprovided where appropriate.

Filament and arc tube close-up.

Box in different orientations.

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Instructions included in box.

Lamp packaged in protective polystyrene.

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Grammaticalerror

Lamp and markings. Note the grammatical error.

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UV
PERFORMANCE

The instructions state that this lamp is only supposed to be used
overhead.
As it can be presumed that most average consumers will not burn-in
their lamp (there is no instruction to do so on the box), I havemeasured the UV as it degrades over the first 100 hours of use.
I have measured the UVI (Solarmeter 6.5), and the UVB in µW/cm²(Solarmeter 6.2) at 30cm (approx. 12”) from the centre point of thelamp every 10 hours for the first 100 hours of use.

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BURN-IN AND DEGREDATIONThe below measurements were taken at 30cm (approx. 12 inches)from the centre point of the lamps over the first 100 hours of burn-in.
No reflector or dome is used for this test.

0Age (hrs)
Lamp
3

(10
mins
warmup)

UVB
UVI

131
5.5

10

20

30

40

50

60

70

80

90

100

129 126 122 118 116 109 109 108 107 107
5.4 5.1 4.9 4.9 4.8 4.7 4.7 4.6 4.6 4.6

The following is a graph of the above data, showing how the UVB
decays over time at 30cm.
Zoo Med 65W CFL UVB Decay over 100 hours of burn-in
140
135
130

UVB µWatt/cm²

125
120
115
110
105
100
95
90

Time (Hrs)
0 (10mins
warmup)

10

20

30

40

50

Lamp 3 UVB

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60

70

80

90

100

The following is a graph of the same data, showing how the UVI
decays over time at 30cm.
Zoo Med 65W CFL UVI Decay over 100 hours of burn-in
6

5.5

UVI

5

4.5

4

3.5

3
0
(10mins
warmup)

10

20

30

40

50

Time (Hrs)
Lamp 3 UVI

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60

70

80

90

100

CENTRE POINT AFTER BURN-IN
The below measurements were taken at set distances from the centre
point of the lamps after a 105-hour burn-in. No reflector or dome isused for this test.

Distance
(cm)
UVB
Lamp
3
UVI

0

5

10

15

20

25

30

35

40

45

50

55

2000 990 310 282 195 116 107 90 70 59 46 38 36
195.0 52.0 22.0 13.0 8.2 6.1 4.6 3.5 2.8 2.3 1.9 1.8 1.4

The following is a graph of the above data, showing how the UVBchanges over distance.
h

Zoo Med 65W CFL UVB at set distances from lamp

1400

UVB µWatt/cm²

1200
1000
800
600
400
200
0
0

5

10

15

20

25

30

35

Distance (cm)Lamp 3 UVB

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40

45

50

55

60

The following is a graph of the same data, showing how the UVIchanges over distance.
Zoo Med 65W CFL UVI at set distances from lamp
200.0
180.0
160.0
140.0

UVI

120.0
100.0
80.0
60.0
40.0
20.0
0.0
0

5

10

15

20

25

30

35

Distance (cm)Lamp 3 UVI.

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40

45

50

55

60

IRRADIANCE
CHARTSPURPOSEThe charts in this chapter are an indication of UVI output from thelamps at set distances.
It is possible to visualise how the lamps emit UVB as a whole, using
UVI as a figure.

DISCLAIMER
The charts do not make claim to the safety of the lamps, as there is nodata on the spectrum included in the charts. The charts are a guide
only.
The charts are to scale.

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LAMP 3 – NO REFLECTORThis is the ISO Irradiance Chart for Lamp 3 without a reflector or“dome”. Commentary is on a later section.

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LAMP 3 – WITH DEEP DOME FIXTURE
This is the ISO Irradiance Chart for Lamp 3 with the Zoo Med Deep
Dome. Commentary is on a later section.

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LAMP 3 – WITH COMBO DEEP DOME FIXTURE
This is the ISO Irradiance Chart for Lamp 3 with the Zoo Med Combo
Deep Dome reflector, there was also a heat lamp in situ to replicate
real life use. Commentary is on a later section.

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SPECTRAL
MEASUREMENTS

280 – 400NM
Reading taken at 30cm away from the lamp. Lamp warm-up was 30
minutes each. This reading was taken after the lamp had burned-infor 105 hours.

Full page graph is on the next page. Commentary is in a later section.

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250 – 350NM
Reading taken at 30cm away from the lamp. Lamp warm-up was 30
minutes each. This reading was taken after the lamp had burned-infor 105 hours.

Full page graph is on the next page. Commentary is in a later section.

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260 – 800NM
Reading taken at 30cm away from the lamp. Lamp warm-up was 30
minutes each. This reading was taken after the lamp had burned-infor 105 hours.

Full page graph is on the next page. Commentary is in a later section.

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COLOURMEASUREMENTS

OVERVIEW
The spectrometer software is able to calculate colour values based on
the readings from the lamps.
The range of wavelengths used to generate these values is dictated by
the CIE. The range defined is 380nm to 850nm.
These standards are defined as such for human vision only, and they
do not take into consideration reptile vision in the UVA range.
I have also used a wider range (350nm to 800nm) to allow analysis of
typical reptile photoreceptor excitation by software.

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COLOUR VALUES
The lamps each had their colour values checked. Data is below.
Category
CCT (Kelvin)

34

Ref

Lamp 3 Value
6618K

CRI(a)

5.0

R1

18.2

R2

12.4

R3

10.1

R4

-10.2

R5

-8.7

R6

-3.8

R7

9.4

R8

12.3

R9

90.8

R10

-0.2

R11

0.8

R12

40.4

R13

-15.9

R14

41.4

R15

11.4

DC<5.4E-3

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Below is a chart showing excitation of the 3 “cone” visualphotoreceptors used in human vision, as they would be stimulated by
the spectrum in this enclosure. The coloured vertical bars show thecone stimulation level; the short green horizontal bars show theequivalent stimulation by natural sunlight. The chart gives a visual
representation of how well colour is rendered by humans.

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Reptiles have different photoreceptors to humans. And most species
are also different to each other. This makes it difficult to quantify andanalyse light for reptile vision. Basic assumptions can be made though.
Below are the same charts showing excitation of the 3 “cone” visualphotoreceptors used by some reptiles and birds (top), and the samefor “4 cone” visual photoreceptors used by other species of reptile andbirds (bottom), as they would be stimulated by the spectrum in thisenclosure. The coloured vertical bars show the cone stimulation level;
the short green horizontal bars show the equivalent stimulation by
natural sunlight. The chart gives a visual representation of how wellcolour is rendered by different species of reptile or bird.

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Many reptiles see the range 350nm - 800nm and have an additional
UV photoreceptor in their retina. On the left is a representation of atypical “3-cone” reptile’s cone excitation. On the right is the same for atypical “4-cone” reptile.
The lamp colour space graph is below.

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OTHERMEASUREMENTS

OVERVIEW
The spectrometer software is able to ascertain certain values based on
the readings from the lamps. Each reading was taken at 30cm whereappropriate. The lamp was given 30 minutes to warm up before eachtest.
I have listed the Illuminance (Lux), Luminous intensity (Candela),
Power Density (µWatt/cm²), UVB density (250-320nm in µWatt/cm²
using SolarMeter 6.2), UVI (SolarMeter 6.5), SolarMeter Ratio, Power
Factor, and average wattage values.
Integration began at 280nm and ended at 850nm for measurements,
excluding the tests done with the Solarmeter 6.2 and Solarmeter 6.5.
This encompasses the range of UV, Visible Light, and the very shortest
Infrared Wavelengths. Simpson’s rule was used for integration.
This section also contains light spread and thermal imaging.

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MEASURMENTS (AFTER BURN-IN)
The following are readings taken from the lamp after a 105-hour burnin period. No reflector used.
Category

Lamp 3 Value

Lux

1320.2

Candela0.015771

PD µWatt/cm²

843.65(SM6.2) UVB

107(SM6.5) UVI

4.6

SolarMeter Ratio

23.2 : 1

Power Factor

0.62

Average Wattage

35.1

LIGHT SPREAD
The spread of light can be seen as homogenous in the below images.
One image is direct spread, and the other is through a 16mm circularhole. Both are at 30cm distance from the lamp.

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THERMAL IMAGING (AFTER BURN-IN)
The following thermal image was taken of the lamp after a 105-hourburn-in period. The ambient room temperature was approx. 22.5°C.

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COMMENTARYON FINDINGSOVERALL
The lamp worked without any faults during the tests.
The lamp shows no European standard safety markings, but as the
product is not for sale in Europe at the time of writing, this should not
be a problem.

UVI AND UVBThe UVB output from the lamps is impressive for a CFL.
The UVI measured from the lamp was 4.4 at 30cm. This rivals some
T5HO lamps used in high quality reflective fixtures.
The Solarmeter ratio can be used as a way of estimating thebiologically-appropriate UV from a light source. By comparing the ratio
to that of the sun, we can discern how similar or different a lightsource is to sunlight in the UV wavelengths. Sunlight is generally

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shown to have a ratio of 50-55:1 at “full strength”. The average
Solarmeter ratio was 23.7. This is fairly low. A low ratio implies asignificant amount of short-wavelength UVB compared to longer
wavelengths. However, this is normal for a fluorescent lamp.
If we consider what is shown on the box, as discussed in an earlier
section, the UVI at 30cm could be considered too high for many
species. However, I feel that there is sufficient data on the box and in
the packaging to give consumers the insight and ability to make theirown informed choice.
The spread of the UV (in UVI) was similar across the lamps. The small
differences are probably down to the orientation that the lamp was atwhen screwed in. The spread is enough to comfortably cater for an
animal with Ferguson Zone 3 UV requirements, down to Ferguson
Zone 1 requirements.
Below are the advertised “zones” (The box doesn’t explicitly state thatthese are Ferguson Zones, so they could be Zoo Med’s own
equivalents) vs the average measured Ferguson Zones based on all of
the lamps in the different setups. Combi Dome measurements were
measured from centre of the lamp, not the centre of the whole fixture.
Distance from lamp(inches approx., cm
actual)Advertised Zone

No DomeActual Reading(UVI) and Zone

Deep Dome
Actual Reading(UVI) and Zone

Dual Dome
Actual Reading(UVI) and Zone

2”

5cm

Not safe

47.5 - Not safe

47.5 - Not safe

62.1 - Not safe

4”

10cm

Not safe

20.7 - Not safe

22.7 - Not safe

28.1 - Not safe

6”

15cm

Not safe

12.6 - Not safe

13.6 - Not safe

16.1 - Not safe

8”

20cm

Not safe

8.1 - Not safe

9.0 - Not safe

10.4 - Not safe

10”

25cm

Not safe

5.9 - Zone 4

6.4 - Zone 4

7.1 - Not safe

12”

30cm

Zone 44.4 - Zone 3/4

4.7 - Zone 3/4

5.2 - Zone 3/4

14”

35cm

Zone 4

3.3 - Zone 3

3.6 - Zone 3

3.9 - Zone 3

16”

40cm

Zone 4

2.7 - Zone 2

2.9 - Zone 2

3.1 - Zone 3

18”

45cm

Zone 4

2.2 - Zone 2

2.3 - Zone 2

2.5 - Zone 2

20”

50cm

Zone 3

1.8 - Zone 2

2.0 - Zone 2

2.1 - Zone 2

22”

55cm

Zone 3

1.8 - Zone 2

1.8 - Zone 2

1.9 - Zone 2

24”

60cm

Zone 3

1.3 - Zone 1

1.4 - Zone 1

1.5 - Zone 1

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tom@tomaskas.co.uk – www.tomaskas.co.uk

The actual readings show Ferguson Zones that are lower than that on
the box, even with the use of the reflective fixtures.
In these tests, I also found that the fixtures don’t reflect much UVB,
with the Deep Dome increasing readings by approximately 7% and theDual Dome increasing readings by approximately 20%.
The Dual Dome did produce a significantly wider spread of UV.

SPECTRUM AND VITAMIN D3 SYNTHESIS
Below is a graph showing the lamp spectrum compared to biologicalprocesses associated with certain wavelengths of UVB and UVA.
Also included is the solar spectrum at different UVI, for reference. The
spectral plot of the lamp has been displayed at UVI 7.6 for analysis
purposes.

Graph made using Reptile Lamp Database software, Courtesy of Dr Sarina Wunderlich43

tom@tomaskas.co.uk – www.tomaskas.co.uk

In the graph, the lamp’s spectral output can be clearly seen. The
graph shows the following:
1. The lamp does not emit dangerously short-wavelength UVB.
2. The lamp does not emit UVC.
3. There is activity in the wavelengths associated with the synthesis
of Vitamin D3 and regulation of Vitamin D3.

In practical terms, this tells us that the lamp will cause the skin tosynthesise Vitamin D3 safely. It will also allow the safe regulation ofVitamin D3 in the body. This lamp should not cause an overdose of
Vitamin D3, as there is sufficient activity in the wavelengths associatedwith the regulation of Vitamin D3.
There is some activity in the UVA range of wavelengths, however thisis primarily short-wavelength UVA. There is little to no activity
between approximately 370nm and 400nm. This is typical for a
fluorescent lamp.
There isn’t much activity in the visual spectrum, or in the infrared
spectrum. This lamp is not designed to accommodate thosewavelengths significantly, and this is typical of a fluorescent lamp.
The light emitted from the can be broken down as follows. The
measured range for these readings is 280nm to 780nm:

Grouping

W/m2

Percentage of total Measured Range

UVB (280-320nm)

1.06

13.22%UVA (320-400nm)

2.3

28.68%

Visible (400-780nm)

4.66

58.10%

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tom@tomaskas.co.uk – www.tomaskas.co.uk

COLOUR RENDERING AND VISION
The colour, to my eyes, is fairly white with a slight tint towards blue.
However, the lamp doesn’t render colours very well. The skin on myhands appeared pale when illuminated by the lamp.
The light is homogenous. This is to be expected, as there is just one
source and the phosphor coating acts as a frosting.
For a reptile, the lamp would appear close to white. It may have aslight tint towards “UVA-colour” due to the spike in activity at 365nm(a known Mercury Emission Spike).

OTHER COMMENTS
The lamp is not very bright considering the wattage. This is expectedfrom a fluorescent lamp. The Power Factor of the lamp isapproximately 0.62. This is very low and considered poor.
The lamp’s glass was fairly hot when in use, this is to be expected. The
plastic housing for the electronics/ballast also became warm. Taking
into consideration emissivity, it is sometimes best to consider thetemperature of the ceramic socket. The socket did not get unjustly hot
considering the wattage being used.
When used with the respective Zoo Med domes, the lamp protruded
from the base of the domes slightly. Images below show this.

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At the time thermal images were taken, the lamp was using an
average of approximately 35W, which is significantly lower than theadvertised 65W. This lower energy consumption isn’t necessarily a badthing. The lamp showed significant photodegradation (aka “yellowing”)
on the plastic housing. This is normal for CFL lamps, but is unsightly
and could be mistaken for burns by some users. Below is an example.

Zoo Med could utilise cardboard (recycled) for packaging on the insideof the box, this would be a more environment conscious choice of
packaging material.
I feel that this lamp will suffer from “compact lamp syndrome” in thehobby. In circa 2007, many compact lamps were sold and found to be
dangerous – emitting significant amounts of unnaturally-shortwavelength UVB. This caused health problems with reptiles across thehobby. This has somewhat tainted the reputation of compact lamps as
far as keepers are concerned. Although most modern compact lamps
are perfectly safe if used properly, they are still often touted as being
associated with health problems in reptiles.
The Zoo Med 65W Mega Compact Lamp is safe, and if used properly
should not cause eye problems or other health issues in reptiles.

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tom@tomaskas.co.uk – www.tomaskas.co.uk

FURTHER TESTSLONGEVITY AND DEGRIDATION
Zoo Med states that the lamps will emit UVB for 12 months. This was
not tested, although such a test is doable if time was put aside for the
test.

TEARDOWN
At this point I have not conducted a teardown of the lamp. This could
involve reviewing electronics inside, although I may seek further
counsel on this first as I don’t want to break any laws regarding
intellectual property.
These types of lamps are widely used, so I don’t suspect there is any
ground-breaking technology inside to warrant a teardown.

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tom@tomaskas.co.uk – www.tomaskas.co.uk

SPECIAL
THANKSSpecial thanks are in order for many friends, colleagues, and partners.
I’d like to give a thank you to the following, but there are undoubtedly
more that have not been named.

COLLEAGUESDr Sarina Wunderlich has kindly allowed me to utilise her Reptile Lamp
Database system to generate some technical graphs and datasets. She
has also acted as a point of consultation.
Andrew Elston at Zoo Med has acted as a point of contact from Zoo
Med, and answered all my questions with commendable speed.

COPY
Rebecca Baines MA conducted spellchecks and ensured that I was
making sense. She also provided much needed coffee.

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tom@tomaskas.co.uk – www.tomaskas.co.uk

LITERATURE
AND FURTHERREADINGIn this paper, I have made comments supported by scientific
literature, both peer-reviewed and not. Here is a list of literature that I
have either directly referenced, or used in support of points and claims
that I’ve made. The list is not extensive.

PEER-REVIEWED LITERATURE
Holick, M. F (2016) - Biological Effects of Sunlight, Ultraviolet
Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.
Anticancer Research 36: 1345-1356 (2016)
Wacker and Holick (2013) - Sunlight and Vitamin D.
Dermatoendocrinol. Jan 1; 5(1): 51–108.
Christopher J. Laing, Angelika Trube, Glenn M. Shea, and David R.
Fraser (2001) - The requirement for natural sunlight to prevent

49

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vitamin D deficiency in iguanian lizards. Journal of Zoo and Wildlife
Medicine 32(3), 342-348.
Acierno, M.J., Mithcell, M.A., Roundtree, M.K., and Zachariah, T.T.,(2006) - Effects of ultraviolet radiation on 25-hydroxyvitamin D3
synthesis in red-eared slider turtles (Trachemys scripta elegans).
American Journal of Veterinary Research, 67(12), pp. 2046-2049.
MacLaughlin, J., Anderson, R. & Holick, M. F. (1982) - Spectral
character of sunlight modulates photosynthesis of previtamin D3 andits photoisomers in human skin. Science, 216 1001–1003.
Baines, F. M. et al. (2016) - How much UV-B does my reptile need?
The UV-Tool, a guide to the selection of UV lighting for reptiles andamphibians in captivity. Journal of Zoo and Aquarium Research, 4.
Ferguson, G. W. et al. (2010) - Voluntary exposure of some westernhemisphere snake and lizard species to ultraviolet-B radiation in thefield: how much ultraviolet-B should a lizard or snake receive incaptivity? Zoo Biology 29(3), 317-34.
Scott, R. K. et al. (2015) - Evolutionary transformation of rod
photoreceptors in the all-cone retina of a diurnal garter snake. PNAS
113, 2.
Sillman et al. (1999) - The photoreceptors and visual pigments in theretina of a boid snake, the ball python (Python regius). The Journal of
Experimental Biology, 202, 1931–1938.
Kelber, A., Vorobyev, M. & Osorio, D. (2003) - Animal colour vision behavioural tests and physiological concepts. Biological Reviews, 78
81–118.
Katti C, Stacey-Solis M, Coronel-Rojas NA and Davies WIL (2019) The Diversity and Adaptive Evolution of Visual Photopigments in
Reptiles. Front. Ecol. Evol. 7:35.

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tom@tomaskas.co.uk – www.tomaskas.co.uk

Sarika Paul and Timothy M Brown (2019) - Direct effects of the lightenvironment on daily neuroendocrine control. Journal of
Endocrinology, 243:1.
Albers et al. (2019) - Blue light (λ=453 nm) nitric oxide dependently
induces β-endorphin production of human skin keratinocytes in-vitro
and increases systemic βendorphin levels in humans in-vivo. Free
Radical Biology and Medicine 145 78-86.
Grace, Michael S. (1997) - The visual system and non-visualphotoreception. The Biology Husbandry, and Health Care of Reptiles.
Lowell Ackerman, DVM, ed. Vol. I, pp. 325-341.
G. Chen et al. (2017) - Mercury speciation by differential
photochemical vapor generation at UV-B vs. UV-C wavelength.
Spectrochimica Acta Part B 137, 1–7.
C. M. Lerche et al. (2017) - UVR: sun, lamps, pigmentation andvitamin D. Photochem. Photobiol. Sci., 2017, 16, 291-301
Lindgren, J., Gehrmann, W. H., Ferguson, G. W. & Pinder, J. E. (2008)- Measuring Effective Vitamin D3-Producing Ultraviolet B Radiation
Using Solartech’s Solarmeter® 6.4 Handheld, UVB Radiometer.
Bulletin of the Chicago Herpetological Society, 43 57–62.
Holick, M. F. (2016) - Biological Effects of Sunlight, Ultraviolet
Radiation, Visible Light, Infrared Radiation and Vitamin D for Health.
Anticancer Research, 36 1345–1356.
James K. Bowmaker (2012) - Evolution of the Vertebrate Eye. How
Animals See the World: Comparative Behavior, Biology, and Evolutionof Vision 23 441–472.
Tosini et al. (2001) - The circadian system of reptiles: amultioscillatory and multiphotoreceptive system. Physiology &Behavior 72 (2001) 461-471.

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Kalajian, T. A., Aldoukhi, A., Veronikis, T.J., Persons, K.& Holick, M. F.
(2017) - Ultraviolet B Light Emitting Diodes (LEDs) Are More Efficientand Effective in Producing Vitamin D3 in Human Skin Compared to
Natural Sunlight. Scientific Reports, 7 11489.
Sakich and Tattersall (2022) - Regulation of Exposure to Ultraviolet
Light in Bearded Dragons (Pogona vitticeps) in Relation to
Temperature and Scalation Phenotype. Ichthyology & Herpetology
110, No. 3, 2022, 477–488.
Cusack, L., Rivera, S., Lock, B., Benboe, D., Brothers, D. & Divers, S.
(2017) - Effects of a light-emitting diode on the production ofcholecalciferol and associated blood parameters in the bearded dragon(pogona vitticeps). Journal of zoo and wildlife medicine, 48 1120–
1126.

OTHER LITERATURE
Sinclair, Sandra (1985) - How Animals See: Other Visions of Our
World. Croom Helm, London.
Dr Frances M Baines (2021) - Vitamin D3 Synthesis: A self-limiting
process in natural sunlight.
Loos, B. de (Babette) (2016) – Production of cutaneous vitamin D3
after UVB radiation in reptiles and amphibians. Faculty of Veterinary
Medicine Research Internship Department: Biochemistry and Cell
Biology
Baines, F. M. (2008) - Photo-kerato-conjunctivitis in reptiles. In
Proceedings of the Autumn British Veterinary Zoological Society
Meeting. BVZS: UK.
GOV . UK (2022) – Guidance - Using the UKCA marking.
GOV . UK (2022) – Guidance - Using the CE marking.

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