diff --git a/src/suunto_d9_parser.c b/src/suunto_d9_parser.c
index 020a7dc..67fa49a 100644
--- a/src/suunto_d9_parser.c
+++ b/src/suunto_d9_parser.c
@@ -42,6 +42,12 @@
 #define D6i      0x1A
 #define D9tx     0x1B
 
+#define AIR      0
+#define NITROX   1
+#define GAUGE    2
+#define FREEDIVE 3
+#define MIXED    4
+
 typedef struct suunto_d9_parser_t suunto_d9_parser_t;
 
 struct suunto_d9_parser_t {
@@ -185,6 +191,14 @@ suunto_d9_parser_get_field (parser_t *abstract, parser_field_type_t type, unsign
 	if (size < config)
 		return PARSER_STATUS_ERROR;
 
+	// Gas model
+	unsigned int gasmodel_offset = 0x1D - SKIP;
+	if (parser->model == HELO2)
+		gasmodel_offset += 6;
+	if (parser->model == D4i || parser->model == D6i || parser->model == D9tx)
+		gasmodel_offset = 0x1D;
+	unsigned int gasmodel = data[gasmodel_offset];
+
 	gasmix_t *gasmix = (gasmix_t *) value;
 
 	if (value) {
@@ -203,7 +217,9 @@ suunto_d9_parser_get_field (parser_t *abstract, parser_field_type_t type, unsign
 			*((double *) value) = array_uint16_le (data + 0x0D - SKIP) / 100.0;
 			break;
 		case FIELD_TYPE_GASMIX_COUNT:
-			if (parser->model == HELO2) {
+			if (gasmodel == AIR) {
+				*((unsigned int *) value) = 1;
+			} else if (parser->model == HELO2) {
 				*((unsigned int *) value) = 8;
 			} else if (parser->model == D9tx) {
 				*((unsigned int *) value) = 8;
@@ -216,7 +232,10 @@ suunto_d9_parser_get_field (parser_t *abstract, parser_field_type_t type, unsign
 			}
 			break;
 		case FIELD_TYPE_GASMIX:
-			if (parser->model == HELO2) {
+			if (gasmodel == AIR) {
+				gasmix->helium = 0.0;
+				gasmix->oxygen = 0.21;
+			} else if (parser->model == HELO2) {
 				gasmix->helium = data[0x58 - SKIP + 6 * flags + 2] / 100.0;
 				gasmix->oxygen = data[0x58 - SKIP + 6 * flags + 1] / 100.0;
 			} else if (parser->model == D9tx) {