A crucial part of the naica project was to ensure safety measures and work to define other norms and measures in the event of an emergency for the film teams while they were working in the cave. The permanently risky conditions meant that emphasis was placed on the information and medical care for those responsible for the photography and filming, who worked every day for two or three weeks at a stretch. the personnel's medical monitoring provided the opportunity to undertake a medical research project on the effects on humans of exposure to extreme conditions of heat and humidity in the crystal cave.


Giusseppe Giovine checking Alejandro Macías’s
blood pressure and heart rate after coming
out of "the crystal cave."

Medical station at the base camp. Dr. Giuseppe
Giovine checking speleologist
Tullio Bernabei’s vital signs.

A fundamental part of the Naica project was to implement the safety measures outlined by Industrias Peñoles, but it was essential to establish our own safety rules, since the experience of - La Venta Exploring Team - contrasted with the total lack of experience of the- film crew-. Because of the extremely risky conditions prevailing C/Producciones focused in providing information, support and medical attention to the photo and film crew. The nature and intensity of the job required daily work sessions lasting from two to three weeks.

The need for attention of the members of the crew, in matters of health and safety, opened the door to do research through the systematization of the various indicators reported by the participants as a result of the effects of exposure to extreme conditions of heat and humidity, in the Cave of Crystals.

The time spent in the cave varied enormously but was never more than 2 hours a day.


We seriously undertook to follow-up the speleologists and photographers, men and women between 25 and 60 years of age, constantly exposed to extreme heat. The time remaining in the cave varied, but it could not be more than two hours per day according to our safety rules, adding the partial time of up to 10 to 15 cave entries per day. A working day in the external camp could be of up to 12 hours or more. At times the crew worked all night to monitor the correct functioning of the instruments. These working conditions placed the participants at constant risk since they limit physical resistance.

ue to the above, under the coordination of S&F, documents establishing the norms to regulate the work within the cave, and the measures to be taken in case of emergency were prepared, with the participation of Dr. Germán Gonzalez, Giuseppe Giovinne and Dr. Haffid Eleasin Sánchez.


The doctors followed up a group of speleologists and personnel involved in the photographic production, men and women ages 25 to 60, who were constantly exposed to extreme heat.

Germán González checking Manuel Gálvez after
he has emerged from "The Crystal Cave."




As a result of the follow-up and monitoring of participants performing tasks of intense activity in the Cave of Crystals, a Medical Research Project developed.


Project’s proposal:

• To evaluate cardiovascular and pulmonary effects in relation to the time of exposure to heat and humidity, as well as the effects of accumulated exposure during the duration of the expedition on muscular mass, and hepatic and renal functions.

• To compare the protection afforded by the thermal suit to heat exposure, on cardiovascular and pulmonary effects and on muscular mass and hepatic and renal functions.

• To observe signs of illness caused by exposure to heat, under extreme conditions of temperature at 50ªC and 100% humidity, in the Naica Project personnel.

• Create conscience of self-care and risk prevention, insisting in those conditions that favor dehydration and hydro-electrolytic imbalance.

• To establish minimum rules to enter the cave, and evaluate the protection offered by the ice-lined thermal suit and the cold air atomizer, to be able to remain longer in the cave.

Stages of development:

The preliminary protocol was prepared, April-May 2007 – Pilot test with the production team and five speleologists, May 2007 – Physical survey of the Cueva de los Cristales, May 2007 – Evaluation of the pilot test results, July-August 2007 – Preparing the final protocol, August- September 2007 – Drawing up safety regulations October, 2007 – Training in the service of pneumology, October 2007 to perform spirometrics – To integrate the medical team and work crew: spirometer, oxymeter, scale, etc., October-November 2007 – To draw-up the clinical history of the production team and take electrocardiograms and basal spirometers, November 2007 – Physical conditioning of the production team, October-November 2007 – Intensive Research period, 1:21 December 2007

• application of initial questionnaire every 5 days

• physical exploration and taking vital signs daily,

• taking electrocardiograms and spirometers every 5 days

• measuring the urinary density with a reactive tape every 5 days

• taking of laboratory samples at the end.


Dr. Germán González
Dr. Haffid Eleasin Sánchez